Renal fine needle aspiration cytology

OBJECTIVE: To audit and evaluate the pitfalls in renal fine needle aspiration (FNA) cytology. STUDY DESIGN: A retrospective analysis of 180 renal FNAs from 163 patients, encountered at Canberra Hospital, Australian Capital Territory, between June 1989 and July 1997 was undertaken. The FNA procedures had been performed by radiologists under computed tomography (CT) or ultrasound (US) guidance. The study correlated the FNA results with biopsy findings and clinical outcome. RESULTS: The initial cytologic diagnoses included 84 (47%) benign, 6 (3%) atypical, 7 (4%) suspicious, 70 (39%) malignant and 13 (7%) inadequate. Six of the 13 cytologically inadequate group, on further investigation, had malignant histology. The benign cytologic categories contained 79 benign conditions and 5 cases with a malignant outcome. The atypical cytologic group contained 5 benign and 1 malignant case. All nine cytologically suspicious cases had malignant histology. The cytologically malignant group contained 62 malignant, 7 benign and 1 patient lost to follow-up. The sensitivity was 92.5%, specificity was 91.9%, positive predictive value was 89.9%, negative predictive value was 94.0%, and efficacy of the test was 92.2%. CONCLUSION: Renal FNA can provide an accurate diagnosis in most instances; however, aspiration cytology of the kidney has limitations and pitfalls. Low grade renal cell carcinoma has to be differentiated from oncocytoma, angiomyolipoma, renal infarct and reactive conditions. Renal FNA has a high negative predictive value, which is useful in reassuring patients with radiologically and cytologically benign lesions. Negative FNA does not exclude malignancy in the presence of a radiologic suspicion.     

Actinomycosis in fine needle aspiration cytology

Four cases of actinomycosis were diagnosed by fine needle aspiration (FNA) cytology and eight more cases were detected during a review of FNA smears reported as inflammatory. the age of these 12 cases ranged from 20 to 61 years with a median of 35 years. the male to female ratio was 3:1. the common regions of involvement were cervicofacial in seven cases (58.3%), thoracic in three (25.0%) and abdominal in two (16.7%). Four of the seven cervicofacial cases presented with intra-oral masses; the thoracic lesions were pulmonary in location, and the abdominal lesions presented as bowel masses. the possibility of actinomycosis was not considered clinically in any case. the main reason for missed cytodiagnosis in two thirds of the cases appeared to be observer error. It is suggested that when the aspiration smear from a mass is found to be an inflammatory exudate rich in neutrophils, special efforts must be made to look for this microorganism.     

Pitfalls in fine needle aspiration cytology.

A review of pitfalls encountered in fine needle aspiration cytology (FNAC) of all organs and tissues and based mainly on the author's 35-year experience of diagnostic FNAC in clinical practice is presented. Diagnostic difficulties are usually related to deviations from common cytological criteria that may occur in some lesions. Others are due to the effects of the sampling procedure or of the preparation of samples. A few basic rules are proposed, which may help to avoid some of the diagnostic pitfalls.     

Scrape cell-block technique for fine needle aspiration cytology smears

An inconclusive diagnosis on fine needle aspiration cytology (FNAC) may be due to poor spreading and presence of thick tissue fragments despite aspiration of adequate material. Repeat aspiration may not be possible especially when aspirates of deep seated organs have been obtained by image guided techniques. We have resorted to a 'scrape cell-block' (SCB) technique in such cases. In this technique the cellular material on the slides which had already been fixed and stained, was carefully removed by scraping following destaining and then processed as a cell block. SCB interpretation was then compared with the smear diagnosis and histological diagnosis, wherever available. A total of 27 cases were studied. In 12 cases SCB slides added information to the FNAC smears. In 14 cases SCB did not offer any additional information. SCB was inconclusive in one case. Final histological correlation was available in eight cases and the SCB diagnosis was confirmed in six cases, whereas in two cases SCB failed to identify the tumour. Immunocytochemistry (ICC) was done in one case. SCB is a useful technique to make the best use of the available material when reaspiration is difficult.     

Subcutaneous endometriosis diagnosed by fine needle aspiration cytology

The fine needle aspiration cytology (FNAC) of two patients manifesting cutaneous/subcutaneous endometriosis is presented. Endometrial tissue sampled by the aspiration technique manifested different cytologic characteristics as compared to those of endometrial tissue obtained by standard exfoliative methods. A primary difference was the appearance of the endometrial cells in syncytial clusters in the aspirate, in contrast to the three-dimensional clusters seen in exfoliated material. These cases emphasize the need to include endometriosis in the differential diagnosis of palpable lesions of the abdominal wall, especially in women with healed surgical scars, and the role of FNAC in diagnosing such lesions.     

Testicular fine needle aspiration cytology in male infertility

OBJECTIVE: To compare the accuracy of testicular fine needle aspiration and biopsy for diagnostic and therapeutic purposes. STUDY DESIGN: A comparison of testicular fine needle aspiration and biopsy was performed on 34 infertile men over a 2-year period. RESULTS: Concordance of the 2 tests was evident in 88% of cases. In discordant cases fine needle aspiration yielded more than biopsy, considering the existence of secondary spermatocytes and spermatids. Charcot-Bottcher crystalloids were frequently seen in the cytoplasm of Sertoli cells in normal and abnormal spermatogenesis. CONCLUSION: Testicular fine needle aspiration is a simple and cost-effective method of evaluating testicular pathology in male factor infertility. It may yield more diagnostic and therapeutic material than does biopsy.     

Micronucleus scoring in liver fine needle aspiration cytology

C.‐H. Wen, C.‐H. Lin, S.‐C. Tsao, Y.‐C. Su, M.‐H. Tsai and C.‐Y. Chai
Micronucleus scoring in liver fine needle aspiration cytology Objective: This study evaluated the role of the micronucleus (MN) in liver fine needle aspiration (FNA) cytology. Methods: Histological features of 75 cases of hepatocellular carcinoma (HCC), of which 25 were well differentiated, 37 moderately differentiated and 13 poorly differentiated, and 58 benign hepatic lesions (total, 133 cases) were correlated with MN expression observed in FNA smears reported as benign (n = 40), atypical (n = 14), suspicious (n = 30) and malignant (n = 49). Results: Stepwise increases in the MN score (0.4 ± 0.6, 1.2 ± 1.3, 6.3 ± 4.2 and 14.3 ± 8.8) correlated with the degree of cytological abnormality: benign, atypia, suspicious and malignant, respectively. The mean MN scores for well‐, moderately and poorly differentiated HCC were 5.4 ± 2.2, 11.5 ± 4.5 and 24.9 ± 9.1, respectively, which was significantly different between malignant and suspicious (P < 0.0001), between suspicious and atypical (P = 0.008) but not between atypical and benign. The MN scores differed significantly between all degrees of differentiation of HCC and between the HCC and benign hepatic lesions (P < 0.0001). High sensitivity, specificity and accuracy of liver FNA for diagnosing HCC (96%, 98%, and 96%, respectively) were obtained at a cutoff of three for the MN score. Conclusions: The MN score is an effective HCC biomarker and has a good potential use as an ancillary tool for diagnosing HCC using FNA cytology.     

Burkitt-type lymphoma. Diagnosis by fine needle aspiration cytology

Forty cases of lymphoma were categorized as Burkitt-type lymphoma in a study of fine needle aspiration (FNA) smears. These constituted 14.3% of all cases of non-Hodgkin's lymphoma diagnosed between 1974 and 1982. The median age was 22 years in these cases, 81.8% of which had extranodal tumors. The majority of the cells in the smears (59.8% +/- 8.32%) were in the 11 micron to 15 micron size range and 60.3% +/- 10.3% had noncleaved nuclei. An average 71% of the cells contained cytoplasmic and/or nuclear vacuolizations. Nonneoplastic macrophages were present in the smears in 87.5% of the cases. A study of paraffin-embedded sections in 17 cases revealed the characteristic "starry-sky" appearance in 11; in 5 it was not clearly appreciated and in 1 the nonneoplastic macrophages were absent. FNA cytology was found to be quite reliable for arriving at a diagnosis of Burkitt-type lymphoma. More than 50% of the cases were managed without resort to subsequent surgical biopsy. Exploratory laparotomy was avoided in 69% of the cases having abdominal tumors.     

Spermatic granuloma. Diagnosis by fine needle aspiration cytology

Spermatic granulomas may present as tumorlike lesions adjacent to the testis or seminal vesicle and are often associated with infection, trauma or previous surgery. The fine needle aspiration biopsy cytologic findings in three cases of spermatic granuloma are reported. The predominant cytologic features were granulomatous inflammation (nontuberculous and non-foreign body) and spermatozoids (intrahistiocytic or as extracellular spermatic debris). Additional features included lymphoid cells and lymphocytic debris (nuclear tangles), rare plasma cells and eosinophils. Germ cells and acellular (caseous) necrosis were not identified. Well-preserved sheets of epididymal epithelium were occasionally noted. The clinical and cytologic differential diagnoses in such cases are discussed.     

Diagnosis of intestinal malakoplakia by fine needle aspiration cytology

Two cases of intestinal malakoplakia were diagnosed by fine needle aspiration (FNA) cytology. Clinically, these cases were mistaken for a lymphoma and a tuberculosis. Percutaneous abdominal FNA material showed numerous macrophages with the characteristic Michaelis-Gutmann bodies. These bodies were easily identified both inside and outside the macrophages in the smears.     

Calcium oxalate crystals in thyroid fine needle aspiration cytology

OBJECTIVE: To determine the occurrence, distribution and location of calcium oxalate crystals (COCs) in thyroid fine needle cytology specimens. STUDY DESIGN: Thyroid tissues from 60 fine needle aspiration cytology specimens (31 benign and 29 malignant lesions) were reviewed. These lesions were also histologically examined, and their pathologic diagnosis was confirmed. The cytologic slides were examined by normal and polarized light microscopy to determine their size, shape, occurrence, distribution and location. RESULTS: The size and shape of COCs varied from case to case. The total incidence was 45% (benign diseases, 68%; malignant lesions, 21%). No significant relationship between age and occurrence of COCs was found. Benign diseases showed more multifocal than focal distribution of COCs, unlike malignant diseases. Twenty-three (85%) of 27 cases with COCs revealed background location of COCs, especially within thyroid colloid. CONCLUSION: The occurrence of COCs in thyroid fine needle cytology was lower than that in histologic specimens reported in the literature, and COCs were more often identified in benign than malignant lesions. The presence of COCs may be a clue to benign lesions if their distribution is taken into consideration.