Cytologic features of cribriform-morular variant of papillary carcinoma of the thyroid: a case report

BACKGROUND: While the histology of cribriform-morular variant of papillary thyroid carcinoma has been well documented, its appearance on cytologic smears has rarely been described given the rarity of this tumor. CASE: A 28-year-old woman had a neck lump for an unspecified duration for which she sought medical attention. She was previously well, and there was no significant family history of illness. Fine needle aspiration of the thyroid mass disclosed columnar cells with fine to granular chromatin and nucleargrooves associated with papillary fragments and acinar formation. Occasional groups of epithelial cells forming morules, previously unreported on cytology, were present. An excision specimen of the left thyroid nodule revealed morphologic features of cribriform-morular variant of papillary carcinoma of the thyroid. CONCLUSION: A diagnosis of cribriform-morular variant of papillary carcinoma of the thyroid could be established on fine needle aspiration cytology, prompting exclusion of familial adenomatous polyposis and distinguishing it from other, more aggressive variants of thyroid carcinoma, such as columnar cell carcinoma.     

Fine-needle aspiration of mucin-producing thyroid tumors

Objective: Mucin-producing thyroid tumors are extremely rare. Nonetheless, we have encountered three such cases in fine-needle aspiration. We report the cytologic and histologic findings and review the literature. Study Design: Cytologic features were studied on direct smears using Romanovsky stain to detect background substance and Papanicolaou stain to analyze nuclear and cytoplasmic features. The cytologic features were correlated with histology. Mucin was demonstrated by mucicarmine, Alcian Blue/PAS, and Alcian Blue (pH 2.5). Results: The cytologic features related to mucin include: (1) thick luminal mucin globules and signet ring cells aspirated from an 83-year-old woman with a 3-cm signet ring cell follicular adenoma, (2) abundant fluffy mucin containing signet ring cells in cohesive fragments aspirated from a 75-year-old man with the bilateral signet ring cell follicular variant of papillary carcinoma, which is the first case in the English literature, and (3) abundant thin mucoid mucin aspirated from the lymph node of an 86-year-old woman with a 5-cm mucinous poorly differentiated thyroid carcinoma. Conclusion: The occurrence of mucin in thyroid fine-needle aspiration does not necessarily indicate metastasis, and the presence of mucin in cervical lymph nodes does not exclude the thyroid gland as a possible primary.     

Atypical follicular cells with equivocal features of papillary thyroid carcinoma is not a low-risk cytologic diagnosis

Objective: To determine whether or not significant differences in the risk of malignancy exist between subgroups of atypical follicular cells in The Bethesda System for Reporting Thyroid Cytology (TBSRTC) in patients who underwent surgical resection. Study Design: Between 2004 and 2009, consecutive thyroid fine-needle aspirates at our institutions with a cytologic diagnosis of 'atypical follicular cells' were retrieved and subclassified using the diagnosis and diagnostic comment as: (1) atypical follicular cells with equivocal features of papillary carcinoma [cannot exclude papillary thyroid carcinoma (PTC)] and (2) atypical follicular cells, other patterns. The risks of malignancy for excised nodules were calculated and comparisons were made between these subgroups. Categorical analysis was performed using a 2-tailed Fisher's exact test, and p < 0.05 was considered statistically significant. Results: A total of 7,072 thyroid fine-needle aspiration cases were retrieved, with 1,542 (21.8%) having a histologic follow-up. There were 222 (3.1%) cases of 'atypical follicular cells', with 127 (57.2%) having a histologic correlation and 33 having confirmed malignancies. Atypical follicular cells, cannot exclude PTC, have a significantly higher risk of malignancy than atypical follicular cells, other patterns (45.8 vs. 13.9%, p < 0.01). Conclusions: Atypical follicular cells with equivocal features of papillary carcinoma is not a low-risk cytologic diagnosis.     

Atypical epithelial cells, cannot exclude papillary carcinoma, in fine needle aspiration of the thyroid

OBJECTIVE: Atypical epithelial cells, cannot exclude papillary thyroid carcinoma (AEC-PTC), in fine needle aspiration (FNA) of the thyroid is a controversial diagnostic category that might cause a dilemma in patient management. STUDY DESIGN: Eighty-eight thyroid FNA specimens from 86 patients with a diagnosis of AEC-PTC were retrieved from our files in a 10-year period from December 1996 to December 2006. Of the 86 patients, 57 had follow-up histologic diagnoses and were included in this study. The cytologic and histologic materials were reviewed and correlated. RESULTS: Of the 57 patients, all had cytologic atypical features suggestive of PTC. Twenty-five cases of PTC were identified at surgery (44%). Review of the cytologic materials identified the following cytologic features, either alone or in combination strongly associated with PTC at resection: rare intranuclear cytoplasmic invagination (INCI), squamoid cytoplasm and psammoma bodies. CONCLUSION: The most common reasons for rendering the diagnosis of AEC-PTC in FNA of thyroid include rare atypical cells in a cystic thyroid nodule or a background of Hashimoto's thyroiditis. The cytologic features of LNCI, squamoid cytoplasm and psammoma bodies should alert the pathologist. Focal cytologic features of PTC in FNA samples are strongly associated with papillary carcinoma on resection.     

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)     

Macrofollicular encapsulated variant of papillary thyroid carcinoma as a potential pitfall in histologic and cytologic diagnosis. A report of three cases

BACKGROUND: Macrofollicular encapsulated papillary carcinoma (MEPC) is a variant of papillary carcinoma with a favorable clinical course. Its characteristic histologic pattern could be mistaken for that of an adenoma or hyperplastic nodule. Fine needle aspiration of this neoplasm may not show the particular nuclear features of papillary carcinoma, so the cytologic diagnosis may be benign. CASE REPORTS: Three paradigmatic cases of MEPC with different histologic patterns, diagnosed as a follicular neoplasm using fine needle aspiration biopsy (FNAB) are described. Preoperative cytology showed scattered clusters of thyrocytes with prominent nuclear pleomorphism and irregularities and focal oxyphilic changes mixed with colloid and aggregates of typical thyrocytes. The histologic picture exhibits small, neoplastic foci showing a microfollicular structure within an encapsulated neoplasm with a macrofollicular pattern. In microfollicular areas obvious nuclear pseudoinclusions were seldom observed. CONCLUSION: MEPC represents a challenging tumor subtype that infrequently shows the pathognomonic cytologic characteristics of papillary carcinoma, and therefore it is much more difficult to diagnose with a FNAB. Nuclear pleomorphism and irregularity of the nuclear membrane of thyrocytes are clues to this variant, although in some cases a clear-cut preoperative diagnosis cannot be made.     

Cribriform-morular variant of papillary thyroid carcinoma. Report of a case showing morules with peculiar nuclear clearing

BACKGROUND: There have been only 4 reported cases of cribriform-morular variant of papillary thyroid carcinoma (CMVPTC) with cytologic findings from fine needle aspiration. In these reports, the cytologic findings do not fully reflect the histologic characteristics of this entity. We report a case of CMVPTC in which a cribriform pattern without colloid and epithelial morules with peculiar nuclear clearing (PNC) were present in smears, thus fulfilling the criteria for a cytologic diagnosis of CMVPTC. Protein truncation tests for APC molecule abnormality indicated the presence of germline mutation in the patient's APC gene. CASE: A 30-year-old woman had multiple thyroid tumors. Aspiration cytology revealed a large number of round to spindle-shaped atypical-cells showing sheet-like, cribriform, follicular, whorl-like and solid, 3-dimensional arrangements. The cribriform and follicular arrangements did not contain colloid in the lumen. The powdery chromatin pattern characteristic of papillary carcinoma was not observed, but there were scattered intranuclear cytoplasmic pseudoinclusions and grooved nuclei. The nuclei of the atypical cells presenting in the whorl formations showed enlargement, thickened nuclear membranes and entirely clear contents, consistent with PNC. Hyalinelike necrotic cells were also observed in the cell clusters or in the background. Histologic and immunohistochemical findings were typical of CMVPTC. CONCLUSION: The cribriform pattern without colloid, fascicular or whorl formation of spindle cells, and morules with PNC are identifiable on cytologic smears and are sufficiently distinctive to allow a cytologic diagnosis of CMVPTC.     

Papillary breast lesions diagnosed on cytology. Profile of 65 cases

OBJECTIVE: To analyze the cytologic features of nipple discharge and fine needle aspiration (FNA) cytologic smears from breast lesions reported as showing papillary features and to correlate them with histopathologic features. STUDY DESIGN: The study group consisted of FNA smears and/or nipple discharge smears from 65 breast lesions diagnosed on cytology as duct papilloma, papillary lesion, fibrocystic condition, fibroadenoma, papillary neoplasm or papillary carcinoma. Cytomorphologic features assessed included cellularity, cell pattern (clusters, papillary, 3-dimensionality, etc.) and cell characteristics (monomorphism, pleomorphism, apocrine change, plasmacytoid features). Histological material was available for review and cytohistologic correlation in all cases. RESULTS: Forty-six specimens were FNA smears, and 16 were nipple discharge smears; in 3 cases FNA and nipple discharge cytologic smears were available for review. Cytologic study could predict the presence of a papillary pattern in all neoplasms with pure or focal papillary differentiation. There was an overlap in cytomorphologic features between papillary and nonpapillary benign lesions as well as between benign and malignant papillary neoplasms. Frank blood in the aspirate, cell dissociation and atypia, however, were more frequent in the last. CONCLUSION: Overlap of cytologic features in nonneoplastic and neoplastic benign papillary lesions and between benign and malignant papillary neoplasms necessitates histologic evaluation in all cases diagnosed as papillary on cytology. Since 49.2% of lesions showing papillary features on cytology prove to be malignant, all cases reported as papillary on cytology should be excised urgently for histologic assessment.     

Clinicopathologic analysis of fine needle aspiration cytology of the thyroid. A review of 1,613 cases and correlation with histopathologic diagnoses

OBJECTIVE: To evaluate the accuracy of fine needle aspiration (FNA) of thyroid lesions at our institution and to ascertain its usefulness in determining the therapeutic approach. STUDY DESIGN: The authors reviewed the results of 1,613 cases of FNA cytology of thyroid nodules performed from 1999 to 2001 at the Department of Pathology, Chonnam National University Hospital. Cytologic diagnoses were compared with histologic diagnoses in 207 cases that included both FNA and thyroid surgery. RESULTS: The sensitivity for the detection of neoplasms (carcinoma and follicular adenoma) was 78.4% and the specificity 98.2%. A false positive diagnosis was made in 1 case (1.8%) and false negative ones in 28 cases (21.5%). The diagnostic accuracy was 84.4%, with a positive predictive value of 99.0% and negative predictive value of 66.3%. The predictive value of a cytologic diagnosis was 100% in papillary carcinoma. CONCLUSION: FNA is a useful test in determining the therapeutic approach of thyroid lesions.     

Follicular variant of papillary thyroid carcinoma: diagnostic limitations of fine needle aspiration cytology

OBJECTIVE: To study the diagnostic sensitivity and specificity of fine needle aspiration cytology (FNAC) offollicular variant of papillary thyroid carcinoma (FVPTC). STUDY DESIGN: The study group consisted of 390 papillary thyroid carcinoma (PTC) cases diagnosed histologically with thyroidectomy specimens. The FNAC and histopathologic classification were compared in terms of the appearance of FVPTC and non-FVPTC statistically with the chi squared test. Also, several features of the cytologic smears of FVPTC were reviewed. RESULTS: Twelve of the 390 PTC cases were classified as FVPTC histologically. Five of the 12 cases were also reported as FVPTC in the diagnosis by FNAC and the other 7 as the usual type of PTC (UTPTC). There was 1 case classified as UVPTC histologically but FVPTC cytologically. If we use histologic diagnosis as the gold standard, the sensitivity and specificity of FNAC diagnosis of FVPTC were 42% and 83%, respectively. CONCLUSION: FNAC may be a good tool for diagnosing PTC, but it is unreliable to differentiate between FVPTC and UTPTC.     

Papillary carcinoma of the thyroid occurring during pregnancy. Report of a case diagnosed by fine needle aspiration cytology

A case of papillary carcinoma of the thyroid gland occurring during pregnancy in a 29-year-old woman is described. The enlarged thyroid nodule was first detected at 10 weeks of gestation; fine needle aspiration (FNA) of the nodule showed no cytologic evidence of malignancy. Repeat FNA at 30 weeks of gestation produced inadequate material for diagnosis. A final FNA at 38 weeks of gestation showed classic cytologic features of papillary carcinoma, including papillary structures, grooved nuclei and intranuclear cytoplasmic inclusions. After delivery, the patient was treated with total thyroidectomy and cervical lymph node dissection. The enlargement of the nodule in this case during the course of the pregnancy suggests a relationship between pregnancy and the malignant development of thyroid nodules; this is discussed along with the utility of FNA cytology for diagnosing thyroid cancers during pregnancy.     

Hyalinizing trabecular tumor in a background of lymphocytic thyroiditis: a challenging neoplasm of the thyroid

ObjectiveTo describe a case of hyalinizing trabecular tumor (HTT) in a background of lymphocytic thyroiditis that was misdiagnosed as papillary thyroid carcinoma (PTC) based on fine-needle aspiration (FNA) cytologic findings and overtreated with total thyroidectomy.MethodsWe present a case report, including the imaging and pathologic findings, of a 68-year-old woman who presented with a multinodular goiter that was suspicious for PTC.ResultsOn the basis of FNA cytologic findings, she underwent a total thyroidectomy, and histologic examination of the thyroid gland revealed HTT in a background of lymphocytic thyroiditis. Radioiodine treatment was not administered because of the tumor’s low risk profile. No metastatic foci were established under nonsuppressive levothyroxine therapy after 3 years of follow-up.ConclusionsHTT is a challenging entity because of the uncertainty of its nature, the diagnostic challenges,and the mimicry of other types of thyroid tumors. In order to avoid overtreatment, endocrinologists and thyroid surgeons should be aware of the features of HTT, and suspicious cases should be evaluated by experienced cytopathologists. (Endocr Pract. 2011;17:e140-e143)     

Papillary carcinoma of the breast. Cytologic study of nine cases.

OBJECTIVE: To study the cytologic findings of papillary breast carcinoma by fine needle aspiration. STUDY DESIGN: The study group consisted of fine needle aspiration (FNA) specimens of breast tumors from nine patients performed during the period 1988-1997. Eight were female, and one was male. The FNA results were compared with the final histologic diagnosis. RESULTS: The tumor sizes were 4-6.5 cm. The aspirations yielded a good amount of bloody material. The smears revealed high cellularity, papillary clusters, isolated low-to-tall columnar cells, mild to moderate atypia, hemorrhagic background, foam and hemosiderin-laden macrophages, calcification, rare mitoses, palisading row of cells and bipolar cytoplasmic eosinophilic granules. The smears were diagnosed as either suspicious or suggestive of papillary carcinoma. The histologic examination revealed invasive papillary carcinoma. CONCLUSION: Papillary carcinoma of the breast can be diagnosed by using a panel of cytologic findings that includes hypercellularity, papillary clusters, hemorrhagic background, palisading rows of tall columnar cells, cellular atypia and calcification. The interesting finding in this study was the presence of eosinophilic bipolar cytoplasmic granules, which has not been reported before.     

Cytopathology of papillary carcinoma of the thyroid by fine needle aspiration

To delineate the cytologic presentation of papillary carcinoma of the thyroid, the fine needle aspiration smears were studied from 87 surgically proven cases. Six diagnostically useful findings were identified: papillary fronds, monolayered sheets, tissue fragments, intranuclear cytoplasmic inclusions, psammoma bodies and multinucleated giant cells. From 1,500 smears on "cold" nodules of the thyroid, 6 known false-negative and 4 false-positive diagnoses for papillary carcinoma were made. The estimated accuracy of the fine needle aspirate diagnosis of papillary carcinoma is 94%.     

Thin-layer (liquid-based) cytologic findings of papillary squamotransitional cell carcinoma of the cervix. Review of cases over a 4-year period with emphasis on potential diagnostic pitfalls

OBJECTIVE: To describe the thin-layer cytology and diagnostic pitfalls of papillary squamotransitional cell carcinoma of the cervix, with clinical and histologic correlation. STUDY DESIGN: The author reviewed the clinical findings, thin-layer cytology and histologic features of papillary squamotransitional cell carcinoma of the cervix encountered at Pamela Youde Nethersole Eastern Hospital, Hong Kong, during the 4-year period January 1998-March 2002. Strict histologic criteria (basaloid/transitional cell-like cells constituted > 70% of the tumor cell population and papillary/anastomosing, frondlike structures seen in > 70% of tumor tissue in superficial biopsies) were employed in defining this entity. RESULTS: During the study period, 10 biopsy cases of carcinoma of the lower female genital tract (9 in cervix and 1 in vagina) fulfilled the above histologic criteria. Six of them had thin-layer cytology performed The preparations were often of moderate to high cellularity and contained three-dimensional, arborizing, papillary clusters of basal/parabasal cells. Discernible fibrovascular cores were sometimes identified. Occasionally at the papillary surface, the basaloid cells were aligned horizontally. High-power cytology of the tumor cells ranged from bland-looking to high grade squamous intraepithelial lesions (HSILs) and sometimes squamous cell carcinoma. Mitotic figures were commonly identified. Tumor diathesis and dyskeratotic cells were occasional. Koilocytosis was not observed. Subsequent tumor biopsies showed evidence of stromal invasion in 3 cases. CONCLUSION: Papillary squamotransitional cell carcinoma has a distinctive appearance in thin-layer cytologic preparations. The predominance of bland-looking basaloid cells or HSIL cells, together with scantiness of tumor diathesis and carcinoma cells, may lead to underdiagnosis. Recognition of the subtle cytologic features and clinical correlation are essential in arriving at a correct diagnosis.     

Columnar cell variant of papillary thyroid carcinoma. Report of a case with cytologic findings

BACKGROUND: The columnar and tall cell variants of papillary thyroid carcinoma (PTC) are uncommon variants and have generally been regarded as more aggressive forms in comparison to the more common classic papillary and follicular subtypes. Cytologic diagnosis of these rare variants is elusive since the characteristic nuclear features of the usual papillary thyroid carcinoma are very often absent or inconspicuous. We present a case of the columnar cell variant of PTC in a young woman that demonstrates the diagnostic challenge. CASE: A 24-year-old woman presented with a solitary, 3-cm mass in the left aspect of the thyroid. The aspirate consisted of a moderately cellular sampling of sheets, papillary clusters and microfollicles of cells with oval nuclei and uniform, finely granular chromatin. These cells were arranged in a peudostratified manner around well-defined fibrovascular cores. There were no intranuclear inclusions or well-defined nuclear grooves in the cells of the aspirate. There was also absence of colloid despite the presence of well-formed follicles. The resected thyroid revealed a columnar cell variant of PTC. CONCLUSION: The cytologic features of columnar cell-type PTC are at variance with those of classic PTC and are elusive in fine needle aspiration cytology. It is the lack of classic cytologic features of PTC that is distinctly apparent, yet it is the monomorphism of cells in the aspirate, their papillary configuration and their pseudostratification in well-formed fibrovascular cores that are the keys to the diagnosis. Immunohistochemical staining to rule out other thyroid neoplasms can be performed to aid in the diagnosis.     

Thyroid papillary microcarcinoma. Is it really a pitfall of fine needle aspiration cytology?

OBJECTIVE: To assess the role of fine needle aspiration (FNA) of the thyroid in the diagnosis of papillary microcarcinoma. STUDY DESIGN: Eight cases of papillary microcarcinoma were diagnosed by fine needle aspiration. On histologic examination they were found to be adjacent to larger nodules of interest. The microcarcinomas were inadvertently sampled when sampling the larger, dominant nodules. RESULTS: None of the eight dominant nodules were papillary carcinoma; seven were benign lesions, and one was an angioinvasive Hürthle cell carcinoma. In three cases the microcarcinomas were situated within the capsule of a hyperplastic nodule. On histologic examination, five cases had multifocal microcarcinomas, with one case having multiple lymph node metastases. Based on the clinical findings and morphologic features, there were no definitive cytologic findings that could distinguish between "incidental" microcarcinoma and clinically significant papillary carcinoma. CONCLUSION: The detection of microcarcinoma by FNA should not be considered a false positive finding since the exact nature of the lesion cannot be determined until complete histologic evaluation reveals it to be truly incidental and clinically insignificant.     

Papillary Hyperplastic Nodule: Pitfall in the Cytopathologic Diagnosis of Papillary Thyroid Carcinoma

ObjectiveTo identify the pitfalls of overdiagnosing papillary formation as papillary thyroid carcinoma (PTC) in thyroid cytology specimens.MethodsPatients with papillary hyperplastic nodules who had preoperative fine-needle aspiration biopsy (FNAB) were selected for this study. All patients had been diagnosed as having either PTC or lesions suggestive of PTC on preoperative FNAB. Pathology reports, surgical reports, and cytopathology slides were reviewed and analyzed for demographic data, nature of surgery, and pathologic features.ResultsSix women and 2 men with a mean age of 49 years (range, 16-79 years) were included. The lesion size ranged from 1.0 to 3.5 cm. Four patients were diagnosed as having PTC and 4 as having lesions suspicious for PTC. FNAB specimens were available for review in 6 cases. Surgical pathology slides were reviewed in all cases. When cytologic material was evaluated for the morphologic features that led to the misdiagnosis of PTC by comparing it with FNAB specimens of classic variant of PTC, the specimens from these patients showed follicular cells arranged in short, nonbranching papillae in a background of watery colloid and macrophages. The follicular cells were round and demonstrated oncocytic change with nuclear enlargement, prominent central nucleoli, nuclear chromatin clearing, and intranuclear grooves.ConclusionsCaution should be exercised rendering the diagnosis of PTC on FNAB samples when a thyroid lesion shows papillary configurations and oncocytic cells and if convincing nuclear features of PTC are not present. Furthermore, some morphologic features on thyroid aspiration can help differentiate these cases from true PTC. (Endocr Pract. 2008;14:863-868)     

Cytologic criteria of cystic papillary carcinoma of the thyroid

OBJECTIVE: To establish differential cytologic criteria between benign and malignant thyroid cysts. STUDY DESIGN: The study was a retrospective, transverse, analytic, comparative one of 3 groups of patients with nonfunctional thyroid nodules subjected to fine needle aspiration biopsy (FNAB) and surgical resection of the lesions, with histologic study as the diagnostic gold standard. Fifteen cases of cystic papillary carcinomas (group 1) with initial false negative diagnoses, 42 goiters accompanied by cystic degeneration (group 2) and 15 noncystic papillary carcinomas (group 3) were studied. Independent variables were age and sex; dependent variables were the presence of tridimensional fragments, papillae, anisonucleosis, nuclear bars, pseudoinclusions, powdery chromatin, cytoplasmic vacuoles, metaplastic cytoplasm, psammoma bodies, autolysis, multinucleated giant cells, spindle cells, colloid, monolayered laminae and macrophages in FNAB specimens. Statistical analysis was performed by central tendency measures and the chi 2 test. RESULTS: The chi 2 test revealed a statistically significant difference between group 2 and the groups with papillary carcinoma based on the presence of tridimensional fragments, anisonucleosis, nuclear bars, pseudoinclusions, powdery chromatin, cytoplasmic vacuoles, metaplastic cytoplasm and autolysis. CONCLUSION: The above cytologic characteristics must be searched for systematically in the FNAB of every cystic lesion of the thyroid to rule out the presence of cystic papillary thyroid carcinoma and to decrease the rate of false negative results.     

ProGRP as a Novel Biomarker for the Differential Diagnosis of Medullary Thyroid Carcinoma in Patients with Thyroid Nodules

Objective: To investigate the release of progastrin-releasing peptide (ProGRP) in patients with thyroid nodules and the value of ProGRP in fine-needle aspirate washout fluid (FNA-ProGRP) in the differential diagnosis between medullary thyroid carcinoma (MTC) and non-MTC thyroid nodules.Methods: We investigated 2,446 healthy persons and 212 patients with 235 thyroid nodules. They were classified into healthy, nodular goiter, chronic thyroiditis, thyroid follicular neoplasm, papillary thyroid carcinoma, follicular thyroid carcinoma, and medullary thyroid carcinoma. The serum ProGRP and FNA-ProGRP were measured.Results: The serum ProGRP median concentration in MTC was 124.40 pg/mL, significantly higher than in other groups. The cutoff value of serum ProGRP was 68.30 pg/mL, leading to 53.85% sensitivity, 96.98% specificity, and 0.51 kappa value in MTC. The FNA-ProGRP median concentration in MTC nodules was 2,096.00 pg/mL, significantly higher than in other groups. A receiver operating characteristic analysis of MTC nodules and non-MTC nodules indicated that the cutoff value was 22.77 pg/mL, leading to 94.12% sensitivity, 98.27% specificity, and 0.85 kappa value.Conclusion: FNA-ProGRP measurement could be served as an ancillary method for the differential diagnosis between MTC and non-MTC thyroid nodules.Abbreviations: CEA = carcinoembryonic antigen; CT = calcitonin; FNAC = fine-needle aspiration cytology; FNA-CT = calcitonin in fine-needle aspirate washout fluid; FNA-ProGRP = ProGRP in fine-needle aspirate washout fluid; MTC = medullary thyroid carcinoma; ProGRP = progastrin-releasing peptide; SCLC = small-cell lung cancer; TM = tumor marker