Tumorigenesis of Papillary Thyroid Cancer Is Not BRAF-Dependent in Patients with Acromegaly

Introduction

Several studies have reported a high frequency of papillary thyroid cancer (PTC) in patients with acromegaly. The aim of this study was to determine the prevalence and predictors of thyroid cancer in patients with acromegaly and to investigate the frequency of the BRAF ^V600E mutation in PTC patients with and without acromegaly.

Materials and Methods

We conducted a retrospective study of 60 patients with acromegaly. Thyroid ultrasonography (US) and US-guided fine needle aspiration were performed on nodules with sonographic features of malignancy. We selected 16 patients with non-acromegalic PTC as a control group. The BRAF ^V600E mutation was analyzed in paraffin-embedded surgical specimens of PTC by real-time polymerase chain reaction, and tumor specimens from patients with PTC were stained immunohistochemically with an antibody against insulin-like growth factor-1 receptor β (IGF-1Rβ).

Results

Thyroid cancer was found in 15 (25.0%) patients. No differences in age, sex, initial growth hormone (GH) and IGF-1 percentage of the upper limit of normal values or treatment modalities were observed between patients with and without PTC. Acromegaly was active in 12 of 15 patients at the time of PTC diagnosis; uncontrolled acromegaly had a significantly higher frequency in the PTC group (60%) than in the non-PTC group (28.9%) (p = 0.030). The BRAF ^V600E mutation was present in only 9.1% (1/11) of PTC patients with acromegaly, although 62.5% (10/16) of control patients with PTC had the mutation (p = 0.007). IGF-1Rβ immunostaining showed moderate-to-strong staining in all malignant PTC cells in patients with and without acromegaly. Significantly less staining for IGF-1Rβ was observed in normal adjacent thyroid tissues of PTC patients with acromegaly compared with those without (p = 0.014).

Conclusion

The prevalence of PTC in acromegalic patients was high (25%). An uncontrolled hyperactive GH-IGF-1 axis may play a dominant role in the development of PTC rather than the BRAF ^V600E mutation in patients with acromegaly.     

Deregulated Expression of Aurora Kinases Is Not a Prognostic Biomarker in Papillary Thyroid Cancer Patients

A number of reports indicated that Aurora-A or Aurora-B overexpression represented a negative prognostic factor in several human malignancies. In thyroid cancer tissues a deregulated expression of Aurora kinases has been also demonstrated, butno information regarding its possible prognostic role in differentiated thyroid cancer is available. Here, weevaluated Aurora-A and Aurora-B mRNA expression and its prognostic relevance in a series of 87 papillary thyroid cancers (PTC), with a median follow-up of 63 months. The analysis of Aurora-A and Aurora-B mRNA levels in PTC tissues, compared to normal matched tissues, revealed that their expression was either up- or down-regulatedin the majority of cancer tissues. In particular, Aurora-A and Aurora-B mRNA levels were altered, respectively, in 55 (63.2%) and 79 (90.8%) out of the 87 PTC analyzed.A significant positive correlation between Aurora-A and Aurora-B mRNAswas observed (p=0.001). The expression of both Aurora genes was not affected by the BRAF^V600E mutation. Univariate, multivariate and Kaplan-Mayer analyses documented the lack of association between Aurora-A or Aurora-B expression and clinicopathological parameterssuch as gender, age, tumor size, histology, TNM stage, lymph node metastasis and BRAF status as well asdisease recurrences or disease-free interval. Only Aurora-B mRNA was significantly higher in T(3-4) tissues, with respect to T(1-2) PTC tissues. The data reported here demonstrate that the expression of Aurora kinases is deregulated in the majority of PTC tissues, likely contributing to PTC progression. However, differently from other human solid cancers, detection of Aurora-A or Aurora-B mRNAs is not a prognostic biomarker inPTC patients.     

The Risk of Thyroid Cancer in Patients with Thyroid Nodule 3 Cm Or Larger

Objective: There are conflicting data on the risk of thyroid cancer in thyroid nodules 3 cm or larger, and few such studies on this issue have been conducted in Asia. This study aimed to examine the risk of thyroid cancer in patients with thyroid nodules 3 cm or larger.Methods: This was a 7-year retrospective study conducted in a tertiary referral hospital in Taiwan. All patients with a thyroid nodule measuring ≥3 cm who underwent thyroid operation with or without fine-needle aspiration biopsy (FNAB) were included. The prevalence rate of thyroid cancer, as well as the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and false-negative rate of FNAB for thyroid nodule ≥3 cm were also examined.Results: A total of 132 patients were included in this study. Thyroid cancer was detected in 19 of 132 (14.4%) thyroid nodules measuring ≥3 cm. The performance of FNAB for detecting cancer in nodules 3 cm or larger without considering other ultrasonography parameters was relatively poor with a sensitivity of 50%, but the specificity (100%), PPV (100 %), and NPV (93.4 %) were excellent.Conclusion: The risk of thyroid cancer for thyroid nodules ≥3 cm in this study was low. The PPV and NPV of FNAB were high for the detection of cancer in large nodules. The decision to perform thyroidectomy should not be solely based on nodule size and should include other factors, such as ultrasound characteristics and surgical risk.     

Increased Pleiotrophin Concentrations in Papillary Thyroid Cancer

Background

Thyroid nodules are common, and approximately 5% of these nodules are malignant. Pleiotrophin (PTN) is a heparin-binding growth factor which is overexpressed in many cancers. The expression of PTN in papillary thyroid cancer (PTC) is unknown.

Method and Findings

74 subjects (age 47 ± 12 y, 15 males) who had thyroidectomy with a histological diagnosis: 79 benign nodules and 23 PTCs (10 classic, 6 tall cell, 6 follicular variant and 1 undetermined). Fine-needle aspiration (FNA) samples were obtained ex vivo from surgically excised tissue and assayed for PTN and thyroglobulin (Tg). Immunohistochemistry (IHC) was performed on tissue sections. In FNA samples, PTN concentration normalized to Tg was significantly higher in PTC than in benign nodules (16 ± 6 vs 0.3 ± 0.1 ng/mg, p < 0.001). In follicular variant of PTC (n = 6), the PTN/Tg ratio was also higher than in benign nodules (1.3 ± 0.6 vs 0.3 ± 0.1 ng/mg, P < 0.001, respectively). IHC showed cytoplasmic localization of PTN in PTC cells.

Conclusion

In ex vivo FNA samples, the PTN to thyroglobulin ratio was higher in PTCs, including follicular variant PTC, than in benign thyroid nodules. The findings raise the possibility that measurement of the PTN to Tg ratio may provide useful diagnostic and/or prognostic information in the evaluation of thyroid nodules.     

Overweight in Adolescence Is Related to Increased Risk of Future Urothelial Cancer

Obesity has been linked to various malignancies, but a clear relation of overweight with urothelial cancer has not been established. We assessed the association between adolescent obesity and future risk for urothelial cancer. Medical data on 1,110,835 Israeli adolescents examined for fitness for military duty between 1967 and 2005 were linked to the National Cancer Registry in this nationwide population‐based cohort study. We used Cox proportional hazards modeling to estimate the covariate‐adjusted hazard ratio (HR) for urothelial cancer associated with BMI measured at age 17. The mean follow‐up of 17.6 ± 10.8 years reflected 19,576,635 person years, during which 661 examinees developed urothelial cancer of the bladder, ureter, or renal pelvis. BMI ≥85th standard percentile in adolescence significantly predicted increased risk of urothelial cancer with a HR (adjusted for year of birth, education and religiosity) of 1.42 (95% confidence interval (CI), 1.13–1.77, P = 0.002). Similar results were observed using the ≥25 kg/m² definition of overweight (HR = 1.36 (95% CI, 1.08–1.72), P = 0.008). Incidence of urothelial cancer was significantly lower in the more educated and among those who attended religious schools. Overweight in adolescence is related to increased risk of future urothelial cancer. In view of the growing incidence of both urothelial cancer and adolescent obesity, our study suggests an avenue for possible prevention of urothelial cancer.     

Metformin Reduces Thyroid Cancer Risk in Taiwanese Patients with Type 2 Diabetes

Background

Whether metformin may affect thyroid cancer risk has not been studied. This study investigated the association between metformin use and thyroid cancer risk in Taiwanese patients with type 2 diabetes mellitus.

Methods

The reimbursement databases of all diabetic patients from 1996 to 2009 were retrieved from the National Health Insurance. An entry date was set at 1 January 2006 and 1,414,723 patients with type 2 diabetes were followed for thyroid cancer incidence until the end of 2009. Incidences for ever-users, never-users and subgroups of metformin exposure using tertile cutoffs for cumulative duration of therapy and cumulative dose were calculated and adjusted hazard ratios were estimated by Cox regression. Additional sensitivity analyses were conducted.

Results

There were 795,321 ever-users and 619,402 never-users, with respective numbers of incident thyroid cancer of 683 (0.09%) and 1,614 (0.26%), and respective incidence of 24.09 and 87.33 per 100,000 person-years. The overall fully adjusted hazard ratio (95% confidence interval) was 0.683 (0.598–0.780), and all categories of the dose-response parameters showed significantly lower risk with P-trends <0.0001. The protective effect of metformin on thyroid cancer incidence was also supported by sensitivity analyses, disregarding age (<50 or ≥50 years) and sex; and was not affected by excluding users of insulin, sulfonylurea, and insulin and/or sulfonylurea respectively, by previous diagnosis of other cancers or by potential detection examinations that might lead to differential diagnosis of thyroid cancer.

Conclusions

This study provides evidence for the first time that metformin use in patients with type 2 diabetes may reduce the risk of thyroid cancer.     

Risk Factors for Developing Hyponatremia in Thyroid Cancer Patients Undergoing Radioactive Iodine Therapy

Background

Due to the alarming increase in the incidence of thyroid cancer worldwide, more patients are receiving postoperative radioactive iodine (RAI) therapy and these patients are given a low-iodine diet along with levothyroxine withdrawal to induce a hypothyroid state to maximize the uptake of RAI by thyroid tissues. Recently, the reported cases of patients suffering from life-threatening severe hyponatremia following postoperative RAI therapy have increased. This study aimed to systematically assess risk factors for developing hyponatremia following RAI therapy in post-thyroidectomy patients.

Methods

We reviewed the medical records of all thyroid cancer patients who underwent thyroidectomy and postoperative RAI therapy from July 2009 to February 2012. Demographic and biochemical parameters including serum sodium and thyroid function tests were assessed along with medication history.

Results

A total of 2229 patients (47.0±11.0 years, female 76.3%) were enrolled in the analysis. Three hundred seven patients (13.8%) of all patients developed hyponatremia; 44 patients (2.0%) developed moderate to severe hyponatremia (serum Na⁺≤130 mEq/L) and another 263 (11.8%) patients showed mild hyponatremia (130 mEq/L<serum Na⁺≤135 mEq/L). In univariate analysis, old age, female sex, presence of hypertension, presence of diabetes, use of thiazide diuretics, use of angiotensin receptor blocker or angiotensin-converting enzyme inhibitors, lung metastasis, and hyponatremia and lower estimated glomerular filtration rate at the start of RAI therapy were significantly associated with hyponatremia in patients undergoing RAI therapy after total thyroidectomy. Multivariate analysis showed that old age, female sex, use of thiazide diuretics, and hyponatremia at the initiation of RAI therapy were independent risk factors for the development of hyponatremia.

Conclusion

Our data suggest that age greater than 60 years, female sex, use of thiazide, and hyponatremia at the initiation of RAI therapy are important risk factors for developing hyponatremia following RAI therapy in post-thyroidectomy patients.     

Thyroid Hormone Replacement Reduces The Risk of Cardiovascular Diseases in Diabetic Nephropathy Patients With Subclinical Hypothyroidism

Objective: Patients with diabetic nephropathy (DMN) have an increased risk of cardiovascular disease (CVD). However, strategies to reduce this risk are limited. Thyroid hormone replacement therapy (THRT) in patients with hypothyroidism has been shown to reduce several surrogate markers of CVD. Therefore, we performed a study to determine if THRT would reduce CVD risk in patients with subclinical hypothyroidism (SCH) and DMN.Methods: This was a retrospective, nonrandomized study of patients with type 2 diabetes, DMN, and SCH. Those with known thyroid dysfunction or taking THRT at baseline were excluded. Patients receiving THRT for at least 180 days were included in the THRT group, while the remaining patients were assigned to the non-THRT group. The primary outcome was CVD events, which included coronary syndrome, cerebrovascular events, and peripheral artery diseases.Results: Among the 257 patients, 83 (32.3%) were in the THRT group. The mean ages were 62.7 ± 12.3 and 66.8 ± 12.4 years in the THRT and non-THRT groups, respectively. The corresponding numbers of male patients were 32 (40.0%) and 94 (53.1%). During a mean follow-up of 38.0 ± 29.2 months, 98 CVD events were observed. Acute coronary syndrome and cerebrovascular event prevalence rates were lower in the THRT group than the non-THRT group, but there was no difference for peripheral artery diseases. Multivariate Cox analysis revealed that THRT was independently associated with a decreased CVD event risk.Conclusion: THRT may decrease the risk of CVD in DMN patients with SCH. Randomized trials are needed to verify this finding.Abbreviations:CV = cardiovascularDMN = diabetic nephropathyeGFR = estimated glomerular filtration ratefT4 = free thyroxineHbA1c = glycosylated hemoglobinHR = hazard ratiohs-CRP = high-sensitivity C-reactive proteinLDL-C = low-density lipoprotein cholesterolSCH = subclinical hypothyroidismT2DM = type 2 diabetesTHRT = thyroid hormone replacement therapyTSH = thyroid-stimulating hormone     

Autoimmune Thyroid Disease: A Risk Factor for Thyroid Cancer

ObjectiveTo examine the relationship between clinical markers of autoimmune thyroid disease and the risk of thyroid cancer in patients with thyroid nodules.MethodsA retrospective cohort analysis was performed in a single clinical practice. In 2, 500 consecutive patients, fine-needle aspiration biopsy (FNAB) was performed on all 3, 658 ultrasonography-positive thyroid nodules that were ≥ 1.0 cm in diameter or ≥ 0.5 cm in diameter with ultrasound features suspicious for thyroid cancer. Serum concentrations of thyroglobulin antibodies (TgAb), thyroid peroxidase antibodies, and thyroid-stimulating hormone were measured before FNAB. Diagnosis of thyroid cancer was based on pathologic analysis of thyroidectomy tissue. Associations of thyroid cancer with the independent variables were determined by multivariate logistic regression analysis and reported as the adjusted odds ratio (OR) with the 95% confidence interval (CI).ResultsThere were 202 patients with malignant thyroid nodules, 51 patients with microscopic unsuspected thyroid cancer distal to the nodule under investigation (found at thyroidectomy), and 2, 247 patients with benign thyroid nodules. To evaluate the association of clinical markers for autoimmune thyroid disease with thyroid cancer, we included all 253 patients with thyroid cancer in the malignant cohort. Thyroid cancer was associated with elevated levels of TgAb (OR = 1.57; CI = 1.11 to 2.23) and age < 55 years (OR = 2.01; CI = 1.45 to 2.78), and a strong trend was demonstrated for association with male sex (OR = 1.45; CI = 0.99 to 2.12). Thyroid cancer was not associated with elevated levels of thyroid peroxidase antibodies.ConclusionIn patients who have thyroid nodules with indications for FNAB, elevated levels of TgAb are associated with thyroid cancer. (Endocr Pract. 2011;17: 201-209)     

Family History of Diabetes is Associated with Increased Risk of Recurrent Diabetic Ketoacidosis in Pediatric Patients

Objective: To determine the relationship between family history of diabetes mellitus (DM) and diabetic ketoacidosis (DKA) recurrence in youth with established type 1 diabetes mellitus (T1DM).Methods: We performed a retrospective chart review of patients with DKA admitted to a pediatric hospital between January, 2009, and December, 2014. We compared patients with recurrent (≥2 admissions) and nonrecurrent DKA (1 admission) and investigated patient level factors, including family history, that may be associated with DKA recurrence in pediatric patients with established T1DM.Results: Of the 131 subjects in the study, 51 (39%) subjects were in the recurrence group. Age ≥15 years old, public health insurance, and family history of T1DM or type 2 diabetes mellitus were associated with recurrent DKA admissions in both univariable and multivariable analyses. Family history was associated with DKA recurrence, with an incidence rate ratio of 1.5 (95% confidence interval = 1.0 to 2.3; P = .03). The association was not explained by type of familial diabetes, first degree relative status, or whether the family member lived in the household.Conclusion: Recognition that a positive family history of DM may be associated with a higher risk for DKA recurrence in patients with established T1DM may allow for targeted education and focus on a previously unidentified population at increased risk for DKA. Understanding the mechanism underlying the effect of family history of diabetes on the rates of DKA in patients with established T1DM may allow for improved identification and education of patients who may be at risk for DKA recurrence.Abbreviations: CI = confidence interval; DKA = diabetic ketoacidosis; EHR = electronic health record; IBD = inflammatory bowel disease; IRR = incidence rate ratio; T1DM = type 1 diabetes mellitus; T2DM = type 2 diabetes mellitus     

Increased Intraocular Pressure and Hyperglycemic Level in Diabetic Patients

Purpose

To determine whether hyperglycemic levels as determined from high hemoglobin A1c (HbA1c) levels influence intraocular pressure (IOP) in patients with non-proliferative diabetic retinopathy (NPDR).

Methods

A retrospective chart review was performed on subjects with a diagnosis of NPDR and a corresponding HbA1c level measured within 90 days before or after an IOP measurement over a two-year period. Exclusion criteria included a diagnosis of glaucoma or treatment with IOP lowering medications or oral or topical steroids.

Results

Using 14.5mmHg as a baseline mean value for IOP, 42 subjects had an IOP < 14.5mmHg and mean HbA1c of 8.1±1.1, while 72 subjects had an IOP ≥ 14.5mmHg and a mean HbA1c of 9.0±2.1. Although there was an overlap in the confidence intervals, a significant difference (P = 0.01) in the mean HbA1c level was observed in regression analysis between the two groups. Importantly, diabetic subjects with elevated HbA1c levels rarely (<1%) exhibited reduced IOP levels.

Conclusions

Diabetic subjects with elevated HbA1c levels exhibited significantly higher IOPs compared to those with lower HbA1c levels. Findings from this study indicate an association between hyperglycemia and elevated IOP and that poor glycemic control may contribute to increased IOP levels in long-term diabetic patients.     

Increased Postprandial Nonesterified Fatty Acid Appearance and Oxidation in Type 2 Diabetes Is Not Fully Established in Offspring of Diabetic Subjects

Background

It has been proposed that abnormal postprandial plasma nonesterified fatty acid (NEFA) metabolism may participate in the development of tissue lipotoxicity and type 2 diabetes (T2D). We previously found that non-diabetic offspring of two parents with T2D display increased plasma NEFA appearance and oxidation rates during intravenous administration of a fat emulsion. However, it is currently unknown whether plasma NEFA appearance and oxidation are abnormal during the postprandial state in these subjects at high-risk of developing T2D.

Methodology

Palmitate appearance and oxidation rates and glycerol appearance rate were determined in eleven healthy offspring of two parents with T2D (positive family history, FH+), 13 healthy subjects without first-degree relatives with T2D (FH-) and 12 subjects with T2D at fasting, during normoglycemic hyperinsulinemic clamp and during continuous oral intake of a standard liquid meal to achieve steady postprandial NEFA and triacylglycerols (TG) without and with insulin infusion to maintain similar glycemia in all three groups.

Principal Findings

Plasma palmitate appearance and oxidation were higher at fasting and during the clamp conditions in the T2D group (all P<0.05). In the postprandial state, palmitate appearance, oxidative and non oxidative rates were all elevated in T2D (all P<0.05) but not in FH+. Both T2D and FH+ displayed elevated postprandial TG vs. FH- (P<0.001). Acute correction of hyperglycemia during the postprandial state did not affect these group differences. Increased waist circumference and BMI were positively associated with elevated postprandial plasma palmitate appearance and oxidation.

Conclusions/Significance

Postprandial plasma NEFA intolerance observed in subjects with T2D is not fully established in non-diabetic offspring of both parents with T2D, despite the presence of increased postprandial plasma TG in the later. Elevated postprandial plasma NEFA appearance and oxidation in T2D is observed despite acute correction of the exaggerated glycemic excursion in this group.     

Pain Perception Is Increased in Congenital but Not Late Onset Blindness

There is now ample evidence that blind individuals outperform sighted individuals in various tasks involving the non-visual senses. In line with these results, we recently showed that visual deprivation from birth leads to an increased sensitivity to pain. As many studies have shown that congenitally and late blind individuals show differences in their degree of compensatory plasticity, we here address the question whether late blind individuals also show hypersensitivity to nociceptive stimulation. We therefore compared pain thresholds and responses to supra-threshold nociceptive stimuli in congenitally blind, late blind and normally sighted volunteers. Participants also filled in questionnaires measuring attention and anxiety towards pain in everyday life. Results show that late blind participants have pain thresholds and ratings of supra-threshold heat nociceptive stimuli similar to the normally sighted, whereas congenitally blind participants are hypersensitive to nociceptive thermal stimuli. Furthermore, results of the pain questionnaires did not allow to discriminate late blind from normal sighted participants, whereas congenitally blind individuals had a different pattern of responses. Taken together, these results suggest that enhanced sensitivity to pain following visual deprivation is likely due to neuroplastic changes related to the early loss of vision.     

Increased Risk of Cerebrovascular Events in Patients with Cancer Treated with Bevacizumab: A Meta-Analysis

Arterial ischemia and hemorrhage are associated with bevacizumab, an inhibitor of vascular endothelial growth factor that is widely used to treat many types of cancers. As specific types of arterial ischemia and hemorrhage, cerebrovascular events such as central nervous system (CNS) ischemic events and CNS hemorrhage are serious adverse events. However, increased cerebrovascular events have not been uniformly reported by previous studies. New randomized controlled trials (RCTs) have been reported in recent years and we therefore conducted an up-to-date meta-analysis of RCTs to fully characterize the risk of cerebrovascular events with bevacizumab. We searched the databases of PubMed, Web of Science, and the American Society of Clinical Oncology conferences to identify relevant clinical trials up to February 2014. Eligible studies included prospective RCTs that directly compared patients with cancer treated with and without bevacizumab. A total of 12,917 patients from 17 RCTs were included in our analysis. Patients treated with bevacizumab had a significantly increased risk of cerebrovascular events compared with patients treated with control medication, with a relative risk of 3.28 (95% CI, 1.97–5.48). The risks of CNS ischemic events and CNS hemorrhage were increased compared with control, with RRs of 3.22 (95% CI, 1.71–6.07) and 3.09 (95% CI, 1.36–6.99), respectively. Risk varied with the bevacizumab dose, with RRs of 3.97 (95% CI, 2.15–7.36) and 1.96 (95% CI, 0.76–5.06) at 5 and 2.5 mg/kg/week, respectively. Higher risks were observed in patients with metastatic colorectal cancer (RR, 6.42; 95% CI, 1.76–35.57), and no significant risk was observed in other types of tumors. In conclusion, the addition of bevacizumab significantly increased the risk of cerebrovascular events compared with controls, including CNS ischemic events and CNS hemorrhage. The risk may vary with bevacizumab dose and tumor type.     

Resident Participation During Revision Total Knee Arthroplasty Is Not Associated With Increased Risk of 30-Day Postoperative Complication

BackgroundAcademic teaching institutions perform approximately one third of all orthopedic procedures in the United States. Revision total knee arthroplasty (rTKA) is a complex and challenging procedure that requires expertise and extensive planning, however the impact of resident involvement on outcomes is poorly understood. The aim of the study was to investigate whether resident involvement in rTKA impacts postoperative complication rates, operative time, and length of hospital stay (LOS).MethodsThe American College of Surgeons National Surgical Quality Improvement Program registry was queried to identify patients who underwent rTKA procedures from 2006-2012 using CPT codes 27486 and 27487. Cases were classified as resident involved or attending only. Demographics, comorbidities, and 30-day postoperative complications were analyzed. Multiple logistic regression analysis was performed to identify independent risk factors for increased 30-day postoperative complications. Wilcoxon rank sum tests were performed to determine the impact of resident involvement on operative time and LOS with significance defined as p<0.05.ResultsIn total, 2,396 cases of rTKA were identified, of which 972 (40.6%) involved residents. The two study groups were similar, however the resident involved cohort had more patients with hypertension and ASA class 3 (p=0.02, p=0.04). There was no difference in complications between the cohorts (No Resident vs Resident-involved: 7.0% vs 6.7%, p=0.80). Multivariate analysis identified obesity (OR: 1.81, 95% CI: 1.18-2.79, p=0.01), morbid obesity (OR: 1.66, 95% CI: 1.09-2.57, p=0.02), congestive heart failure (OR: 5.97, 95% CI: 1.19-24.7, p=0.02), and chronic prosthetic joint infection (OR: 3.16, 95% CI: 2.184.56, p<0.01), as independent risk factors for 30-day complications after rTKA. However, resident involvement was not associated with complications within 30-days following rTKA (OR: 0.91, 95% CI: 0.65-1.26, p=0.57). Resident involvement was associated with increased operative time (p<0.001) and LOS (P<0.001).ConclusionResident involvement in rTKA cases is not associated with an increased risk of 30-day postoperative complications. However, resident operative involvement was associated with longer operative time and length of hospital stay. Level of Evidence: III     

Placental Lactogen Is Expressed but Is Not Translated into Protein in Breast Cancer

Introduction

Several studies reported that the pregnancy-specific hormone placental lactogen (hPL) is expressed at both mRNA and protein levels in breast cancer. The overall objective was to establish hPL, the product of the CSH1 and CSH2 genes, as a biomarker for breast cancer.

Methods

CSH expression was determined at the mRNA level in breast cancer cell lines (BCC) and primary carcinomas by real-time and conventional PCR and the products verified as CSH1 by sequencing. Expression of hPL protein was examined by western blots and immuno-histochemistry, using commercial and custom-made polyclonal and monoclonal antibodies.

Results

Variable levels of CSH mRNA were detected in several BCC, and in some primary tumors. We detected a protein, slightly larger than recombinant hPL by western blotting using several antibodies, leading us to postulate that it represents an hPL variant (‘hPL’). Furthermore, some monoclonal antibodies detected ‘hPL’ by immunohistochemistry in breast carcinomas but not in normal breast. However, further examination revealed that these antibodies were non-specific, as efficient suppression of CSH mRNA by shRNA did not abolish the ‘hPL’ band. Custom-made monoclonal antibodies against recombinant hPL detected hPL of the correct size in placental lysate and hPL-overexpressing BCC, but not in unmodified cells or primary carcinomas. hPL protein was detected only when mRNA was increased several thousand fold.

Conclusions

We call into question previous reports of hPL expression in breast cancer which relied on mRNA levels as surrogates for protein and/or used improperly validated antibodies to measure hPL protein levels. Our data suggests that an inhibitory mechanism(s) prevents translation of CSH mRNA in breast cancer when not highly expressed. The mechanism by which translation of CSH mRNA is inhibited is intriguing and should be further investigated.     

Thyroid Cytology and Risk of Thyroid Cancer: Differences Among Indeterminate Specimens

ObjectiveTo assess the potential for stratification of indeterminate cytologic findings on fine-needle aspiration (FNA) of thyroid nodules in an effort to improve therapeutic strategies.MethodsWe attempted to determine the malignant risk associated with various indeterminate FNA cytologic patterns by correlation of specimens with the final histologic diagnosis. For this analysis, we identified 294 computerized medical records of surgically treated thyroid nodules during a 5-year period at our institution with the corresponding FNA cytology reports available.ResultsOf the 294 surgical cases, 162 with a positive or indeterminate cytologic report were selected, reviewed, and classified. Of 52 patients with positive cytologic findings on FNA, 51 (98%) had a final histologic report of a malignant thyroid nodule. Of 110 patients with indeterminate specimens, 30 (27%) had a final histologic diagnosis of thyroid carcinoma. The presence of nuclear atypia was predictive of thyroid carcinoma in 75% of patients, a Hürthle cell cytologic pattern was associated with a malignant thyroid nodule in 33%, and a hypercellular smear was suggestive of malignant involvement in 26% of cases. The lowest rate of malignant potential was associated with cytologic microfollicular and scant colloid alone subtype (6%).ConclusionThe results of this study show that indeterminate thyroid cytologic specimens can be subdivided into groups with different malignant risks. A microfollicular cytologic pattern in the absence of a hypercellular smear or nuclear atypia does not support a recommendation of surgical treatment. A malignant cytologic diagnosis has a high positive predictive value for detection of thyroid cancer. (Endocr Pract. 2004;10:330-334)     

Human Insulin Does Not Increase Bladder Cancer Risk

Background

Whether human insulin can induce bladder cancer is rarely studied.

Methods

The reimbursement databases of all Taiwanese diabetic patients from 1996 to 2009 were retrieved from the National Health Insurance. An entry date was set at 1 January 2004 and a total of 785,234 patients with type 2 diabetes were followed up for bladder cancer incidence until the end of 2009. Users of pioglitazone were excluded and the period since the initiation of insulin glargine (marketed after the entry date in Taiwan) was not included in the calculation of follow-up. Incidences for ever-users, never-users and subgroups of human insulin exposure (using tertile cutoffs of time since starting insulin, duration of therapy and cumulative dose) were calculated and the hazard ratios were estimated by Cox regression.

Results

There were 87,940 ever-users and 697,294 never-users, with respective numbers of incident bladder cancer of 454 (0.52%) and 3,330 (0.48%), and respective incidence of 120.49 and 94.74 per 100,000 person-years. The overall hazard ratios (95% confidence intervals) indicated a significant association with insulin in the age-sex-adjusted models [1.238 (1.122–1.366)], but not in the model adjusted for all covariates [1.063 (0.951–1.187)]. There was also a significant trend for the hazard ratios for the different categories of the dose-response parameters in the age-sex-adjusted models, which became insignificant when all covariates were adjusted.

Conclusions

This study relieves the concern of a bladder cancer risk associated with human insulin. Appropriate adjustment for confounders is important in the evaluation of cancer risk associated with a medication.     

Significantly Increased Risk of Cancer in Patients with Diabetes Mellitus: A Systematic Review and Meta-Analysis

ObjectiveTo conduct a review and meta-analysis of the effect of diabetes mellitus on the incidence of and mortality attributable to cancer at any anatomic site.MethodsWe performed a search of MEDLINE and the Cochrane Library for pertinent articles published from the origin of these databases to July 5, 2010, and included them in a qualitative review and meta-analysis of the risk of all-cancer incidence and mortality in patients with diabetes.ResultsAmong patients with diabetes (n = 257,222) in 12 cohort studies, the cancer incidence was about 7%. The cancer mortality was approximately 3% among patients with diabetes (n = 152,091) in 19 cohort studies. The pooled adjusted risk ratio (RR) of all-cancer incidence was significantly elevated—RR, 1.10 (95% confidence interval [CI], 1.04 to 1.17) overall; RR, 1.14 (CI, 1.06 to 23) for men; and RR, 1.18 (CI, 1.08 to 1.28) for women. Diabetes was also associated with an increased RR of mortality across all cancer types—RR, 1.16 (CI, 1.03 to 1.30) overall; RR, 1.10 (CI, 0.98 to 1.23) for men; and RR, 1.24 (CI, 1.11 to 1.40) for women.ConclusionCancer prevention and early detection by appropriate screening methods in patients with diabetes should be important components of clinical management and investigation, inasmuch as the exponentially increasing prevalence of diabetes will translate into substantial clinical and public health consequences on a global scale. (Endocr Pract. 2011;17:616-628)     

Increased Lymph Node Yield in Colorectal Cancer Is Not Necessarily Associated with a Greater Number of Lymph Node Positive Cancers

The presence of lymph node metastasis is a key prognostic factor in colorectal cancer and lymph node yield is an important parameter in assessing the quality of histopathology reporting of colorectal cancer excision specimens. This study assesses the trend in lymph node evaluation over time in a single institution and the relationship with the identification of lymph node positive tumours. It compares the lymph node yield of a contemporary dataset compiled from the histopathology reports of 2178 patients who underwent surgery for primary colorectal cancer between 2005 and 2012 with that of a historic dataset compiled from the histopathology reports of 1038 patients who underwent surgery for colorectal cancer at 5 yearly intervals from 1975 to 2000. The mean lymph node yield was 14.91 in 2005 rising to 21.38 in 2012. In 2012 92.9% of all cases had at least 12 lymph nodes examined. Comparison of the mean lymph node yield and proportion of Dukes C cases shows a significant increase (Pearson correlation = 0.927, p = 0.001) in lymph node yield while there is no corresponding significant trend in the proportion of Dukes C cases (Pearson correlation = −0.138, p = 0.745). This study shows that there is increasing yield of lymph nodes from colorectal cancer excision specimens. However, this is not necessarily associated with an increase number of lymph node positive cancers. Further risk stratifying of colorectal cancer requires consideration of other pathological parameters especially the presence of extramural venous invasion and relevant biomarkers.