Analysis of fine needle aspiration cytology of the breast: a review of 1,297 cases and correlation with histologic diagnoses

OBJECTIVE: To evaluate the accuracy of fine needle aspiration (FNA) cytology of the breast and to ascertain its usefulness. STUDY DESIGN: The authors reviewed 1,297 cases of FNA cytology of the breast which were performed at Chonnam National University Hospital from 1999 to 2002. Cytologic diagnoses were compared with histologic diagnoses in 457 cases that underwent both cytologic and histologic examination. RESULTS: Of 1,297 cases, 1,201 (92.6%) were satisfactory and 96 (7.4%) unsatisfactory. Subsequent histologic examination was performed on 291 cases (29.7%) out of 981 "benign" lesions, 28 (73.7%) of 38 "suspicious," 124 (68.1%) of 182 "malignant" and 14 (14.6%) of 96 "unsatisfactory." FNA cytology revealed 77.7% sensitivity, 99.2% specificity, 98.4% positive predictive value and 88.0% negative predictive value. Diagnostic accuracy was 91.1%. Of the 291 benign cases on cytology, 35 cases were malignancy on histology. Of the 124 cases reported as malignant, 2 were benign. Interpretive error was the leading cause of false positive diagnoses. CONCLUSION: Although FNA cytology is a useful diagnostic procedure for the evaluation of breast lesions, it should be combined with other diagnostic modalities, such as physical examination, ultrasonography and mammography.     

Fine needle aspiration cytology of primary bone lesions

Fine needle aspiration (FNA) cytologic findings were compared with the results of conventional histology in a series of primary bone lesions to determine the diagnostic accuracy of FNA cytology. The series included 12 osteogenic sarcomas, 4 Ewing's sarcomas, 3 chordomas, 3 myelomas, 2 chondrosarcomas, 2 undifferentiated sarcomas and 1 case each of normal bone and marrow elements, lymphoma and giant-cell tumor. All aspirates yielded adequate material for smear diagnosis, and all 29 cases were correctly identified as benign or malignant by cytology. In 19 cases (66%), specific cytologic diagnoses were rendered and histologically confirmed. This series is compared with other published series of bone aspirations in terms of technique, accuracy and ability to obtain diagnostic material. The importance of technique, radiographic investigations and experience in performing the aspirations in achieving a high diagnostic yield is emphasized.     

Fine needle aspiration cytodiagnosis of liver tumors

OBJECTIVE: To present our experience with liver fine needle aspiration (FNA) diagnosis and the adjunctive use of cell blocks with reticulin stain. STUDY DESIGN: The authors reviewed the results of cytopathologic diagnosis obtained by FNA biopsy over a 1-year period, from January 2000 to December 2000, in patients who presented primarily with ultrasonographically suspected liver nodules. FNA smears from 936 patients and cell blocks from 796 patients were reviewed. RESULTS: Among the 936 aspirates studied, the most common malignancy was hepatocellular carcinoma (HCC), which was diagnosed in 427 cases (45.6%), followed by metastatic adenocarcinoma, with 52 cases (5.6%). The concurrent cell block was available in 796 cases. Among them, 574 (72.1%) contained sufficient tissue for diagnosis. Combining analysis of cytologic and histologic specimens, the sensitivity of ultrasound-guided FNA for diagnosis of liver tumors was 85.1% and the specificity 98.7%. The results were better than isolated cytologic analysis, which gave a sensitivity of 78.4% and specificity of 97.4%. The lower diagnostic accuracy of cytology resulted mainly from its lower ability to distinguish well-differentiated HCC from benign lesions. In the cell block sections with reticulin stain, all HCCs showed a decreased or absent reticulin pattern, whereas all the benign hepatocellular lesions usually had a normal trabecular reticulin framework. CONCLUSION: FNA cytology assisted by cell block examination can be an accurate and minimally invasive method for the definitive pathologic diagnosis of primary benign and malignant liver masses and for confirmation of tumors metastatic to the liver. In addition, reticulin staining should be part of the routine assessment of cell blocks. It enhances diagnostic accuracy, particularly for well-differentiated HCC.     

Cytodiagnosis of bone tumors by fine needle aspiration

A retrospective study was undertaken of bone lesions examined by preoperative fine needle aspiration (FNA) cytology in our hospital during the ten-year period from 1970 to 1979. The 430 cytologically examined lesions were classified into three groups: inflammatory lesions, tumorlike lesions and tumors. A total of 54 patients had undergone surgery, with most of the lesions in those cases proven to be tumors or tumorlike by histologic study. Correlation between the histologic and FNA cytologic findings showed complete compatibility in 76% of the cases, partial compatibility in 13% and incompatibility in 11%. It is concluded that FNA biopsy is appropriate for identifying bone tumors and tumorlike lesions if sufficient numbers of tumor cells are obtained for morphologic examination. Although aspiration cytodiagnosis can be of considerable value in the recognition of certain bone lesions, it cannot replace formal tissue biopsy in the diagnosis of primary bone neoplasms. The morphology of several common bone tumors is described in detail and their differential diagnosis is discussed.     

Beyond the suspicious thyroid fine needle aspirate. A review

Fine needle aspiration (FNA) is currently the best diagnostic tool for thyroid nodules. However, the cytologic category of indeterminate or suspicious lesion, which is found in 10-15% of cases, remains a challenge. Since neither clinical presentation nor intraoperative frozen section is often helpful in differentiating these lesions and since surgical procedures for benign and malignant lesions differ, there is a clear need to develop ancillary tests. In this review we identify 12 potential markers of thyroid malignancy that have been examined in thyroid cytologic samples. Although many of these markers hold promise as adjuncts to FNA cytology, multicenter studies have often shown limitations in the predictive value of these assays due to lack of specificity, sensitivity or both. The recent development, however, of tissue microarray techniques to validate promising new markers suggests that improvements in the approach to indeterminate thyroid FNA samples may soon be at hand. This review presents a summary of the issues facing the development of a clinically useful diagnostic test in the differential diagnosis of thyroid nodules.     

Ultrasound-guided fine needle aspiration cytology of impalpable breast lesions in a rural setting. Comparison of cytology with imaging and final outcome

OBJECTIVE: To analyze the effectiveness of fine needle aspiration (FNA) cytology in a multidisciplinary setting in rural Australia and to compare the imaging (mammographic and ultrasound) appearances and cytomorphologic findings with the final outcome. STUDY DESIGN: Prospective analysis of ultrasound-guided FNA cytology results from 426 women, aged 40-86 years, with screening-detected mammographic abnormalities. Cases of microcalcification, assessed mainly by stereotactatic core biopsy, were not included in the study. The FNAs were performed at a rural breast screening and assessment program in New South Wales, Australia, over a three-year period between May 1993 and May 1996. RESULTS: Imaging, FNA and combined imaging and FNA results from 426 women were as follows. The imaging diagnoses included 176 (41%) benign, 34 (8%) probably benign, 17 (4%) equivocal, 104 (24%) suspicious and 95 (23%) malignant cases. The FNA findings showed 59 (14%) no epithelial cells seen (nondiagnostic), 175 (41%) benign, 36 (8%) atypical, 41 (10%) suspicious and 115 (27%) malignant. Combined imaging and cytologic results comprised 224 (52.6%) benign, 10 (2.3%) atypical/equivocal, 59 (13.9%) suspicious and 133 (31.2%) malignant cases. All the malignant cases, by combined assessment, had malignant histology, and all the benign cases behaved in a benign fashion. In 80% of the suspicious lesions, the histologic diagnosis was malignant, but only 10% of the atypical/equivocal lesions had malignant histology. The positive predictive value of diagnosis of malignancy by combined imaging and FNA was 100%, and the false negative rate was 0%. CONCLUSION: Despite the recent surge in the popularity of core biopsy, FNA cytology of impalpable, mammographically detected lesions, when practiced in a multidisciplinary setting, is an extremely accurate test with high sensitivity, specificity, predictive values and efficacy. FNA cytology of the breast is a well-tolerated, relatively noninvasive test with a very low risk of complications. The sensitivity and positive predictive values for malignant and suspicious mammographic categories are also very high.     

Membrane connectivity estimated by digital image analysis of HER2 immunohistochemistry is concordant with visual scoring and fluorescence in situ hybridization results: algorithm evaluation on breast cancer tissue microarrays

Because metaplastic carcinoma of the breast encompasses a great variety of histopathology, diagnostic challenges abound, especially within the realm of cytology. The authors compiled and studied an eight-case series comprised of metaplastic breast carcinomas and lesions initially suspicious cytologically for metaplastic carcinoma in order to assess the degree of cytologic-histologic correlation and to identify recurring problematic themes surrounding the cytology-based diagnosis of this neoplasm. The cytologic and histologic slides from eight cases suspicious for metaplastic breast carcinoma diagnosed by fine needle aspiration (FNA) were collected and analyzed through a seven-year retrospective search of case files at our institution. Based on cytologic characteristics, the cases were separated into three groups. Group 1 consisted of three cases presenting with poorly differentiated adenocarcinoma and squamoid components on FNA. Group 2 was composed of two cases that featured a monophasic, malignant ductal cell population on cytology, while the cytologic specimens for the third group of cases presented with a mesenchymal component with or without a malignant glandular constituent. Cytologic-histologic correlation was present in two of three cases demonstrating a mesenchymal component, and there was 100% sensitivity in the cytologic detection of those mesenchymal elements. However, in only one of three cases was there an accurate cytologic diagnosis of metaplastic carcinoma when squamoid changes were present on FNA. Both cases demonstrating only malignant glandular elements on cytologic specimens revealed an additional component of malignant squamous differentiation upon the examination of mastectomy-derived tissue. These results indicate that squamous-like changes identified on FNA should be interpreted with caution and that sampling error remains a problematic recurrence in cytology. Regardless, there appears to be promise concerning the accurate cytologic diagnosis of metaplastic carcinoma when the lesion is characterized by a mesenchymal component. A study implementing a larger case number is essential in determining the significance of these findings.     

Ectopic lesions as potential pitfalls in fine needle aspiration cytology: a report of 3 cases derived from the thyroid, endometrium and breast

BACKGROUND: Ectopic lesions are rarely encountered. Those that are derived from thyroid, breast, endometrium and salivary glands present with palpable masses that can mimic malignancy. Fine needle aspiration cytology (FNAC) is a practical procedure for the differential diagnosis of such lesions but can reveal surprising images for a cytopathologist. CASES: Three cases of discrete, ectopic lesions at different locations occurred. Case 1 was a 27-year-old woman. Upon diagnosis of a submandibular mass with a diameter of 1 cm, FNAC was performed. The smears showed crowded thyroid follicular cells comprising papillary clusters. A cytologic diagnosis of papillary thyroid lesion was rendered, Histopathology revealed that this lesion was ectopic thyroid tissue with focal chronic thyroiditis. Case 2 was a 38-year-old woman who presented with a painful mass with a diameter of 2.5 cm in the abdominal wall. The patient had undergone cesarean section 3 years earlier. The case was diagnosed on FNAC as low grade malignancy in which an adenocarcinoma/mesenchymal tumor distinction could not be made. The pathologic examination revealed endometriosis. Case 3 was a 31-year old woman who presented with a palpable nodule in the axillary region with a diameter of 1 cm. The patient had given birth 1 month earlier and was nursing. An FNAC diagnosis of lactation ectopic breast tissue was made. The mass disappeared by the end of lactation. CONCLUSION: FNAC of ectopic lesions may prove to be a diagnostic pitfall for cytopathologists. A cytopathologist who encounters a cellularpicturefrom a lesion that is outside the normal anatomic location must use a cautious diagnostic approach. Unless there are clear findings, the cytopathologist must refrain from a diagnosis of malignancy.     

Fine needle aspiration cytology of soft tissue tumors

OBJECTIVE: To review of the value of fine needle aspiration (FNA) cytology in the diagnosis of soft tissue tumors (STT). STUDY DESIGN: A review of the literature was coupled with the authors' experience with indications, diagnostic specificity and pitfalls; clinical information; and the final cytology report. RESULTS: Over the last few years, FNA has come to be considered a valuable tool in the management of STT in that it affords a specificity of > 90%. FNA is of particular value in any subcutaneous lesion > 5 cm, in all pediatric tumors and whenever direct incision biopsy is particularly contraindicated. Material from aspirates can be used to obtain cytologic smears for conventional staining, special pigment identification, histochemical techniques, cell blocks for paraffin embedding and ancillary techniques (immunocytochemistry, electron microscopy, and densitometric and cytogenetic analyses). The cytologic diagnosis, like its histologic counterpart, should be based on a correct evaluation of clinical data (age, localization, size, effect on bone, nerve and vessel involvement), radiologic information, cytologic findings (architectural pattern, cell and stroma characteristics) and results of special staining techniques. The final cytology report should place the tumor in one of three basic categories: benign, malignant, and inconclusive or undetermined. Wherever possible, a histopathologic diagnosis should also be provided, either based on purely cytologic criteria or aided by ancillary techniques. CONCLUSION: FNA does not present major complications and permits a swift, preliminary diagnosis in a large number of cases. The method is most effective when the aspiration is performed by an experienced pathologist.     

Role and accuracy of rapid on‐site evaluation of CT‐guided fine needle aspiration cytology of lung nodules

A. Fassina, M. Corradin, D. Zardo, R. Cappellesso, F. Corbetti and M. Fassan
Role and accuracy of rapid on‐site evaluation of CT‐guided fine needle aspiration cytology of lung nodules Objective: To prospectively investigate the role of trans‐thoracic fine needle aspiration cytology (FNA) and the value of rapid on‐site evaluation (ROSE) in the clinical management of patients with pulmonary nodules/masses. Computed tomography (CT)‐guided FNA is commonly employed for the diagnosis of lung lesions although its position in the diagnostic work‐up is still a matter of debate. Methods: We reviewed 311 patients (211 males and 100 females, mean age 69.5 years) admitted to the University of Padova from 2004 to 2008, correlating the results of cytology with the available histological findings obtained from biopsies, surgery or autopsy. Results: Smears were adequate in 305 cases (98%) and inadequate in six (2%); a diagnosis of malignancy was achieved in 263 cases (86.2%); 39 cases (12.8%) were classified as non‐malignant; and three cases (1%) were classified as suspect for malignancy. When correlated with histology, FNA with ROSE discriminated malignant versus non‐malignant lesions (Cohen’s kappa 0.78), with three false negatives (sensitivity 96.3%, specificity 100%). Moreover, a satisfactory overall agreement of 71.4% was achieved in differentiating the cancer histological types. Pneumothorax occurred in 13 cases, haemoptysis in four, and chest pain in three. A single aspiration was sufficient in 79.6% of patients; two aspirations were needed in 17.4% and three in 3%. The low complication rate was related to the limited number of aspirations needed due to ROSE. Conclusions: FNA with ROSE is a safe and useful tool in the diagnostic work‐up of lung cancer patients, with no contraindications to its use as the first diagnostic procedure for all patients with peripheral lung lesions. FNA with ROSE should be reconsidered in the guidelines for diagnosing and managing lung cancer.     

Stereotaxic fine needle aspiration cytology of clinically occult malignant and premalignant breast lesions

Stereotaxic fine needle aspiration (FNA) cytology was used to study clinically occult (nonpalpable) breast lesions in 114 consecutive patients with mammographically suspicious findings prior to excisional biopsy. The aspirate contained insufficient material for cytologic evaluation in 15 cases (13.2%), which were histologically diagnosed as benign (7 cases), atypical hyperplasia (7 cases) or carcinoma in situ (1 case). The cytologic findings indicated a benign lesion in 77 cases (67.5%), which were histologically diagnosed as benign (71 cases) or atypical ductal hyperplasia (6 cases). The cytologic sample showed atypia in eight cases (7.0%), which were histologically diagnosed as severe atypical ductal hyperplasia (three cases), carcinoma in situ (one case) or proliferative fibrocystic disease (four cases). In the eight cases (7.0%) cytologically interpreted as probably malignant, histology confirmed six invasive carcinomas, one carcinoma in situ and one fibrocystic disease. Of six cases (4.4%) cytologically reported as malignant, five were histologically diagnosed as invasive carcinoma and one as carcinoma in situ. Overall, stereotaxic FNA cytology reported as malignant or probably malignant 14 of the 15 cases with a histologic confirmation of malignancy, for a sensitivity of 93.3%. Cytology correctly identified 78 of the 83 histologically negative cases, for a specificity of 94.0%. The 16 cases histologically diagnosed as ductal hyperplasia, which carries a high risk for subsequent malignancy, were studied in detail in an effort to define histologic and cytologic criteria for this entity. Using selected histologic criteria, 11 of these cases were graded as showing mild-to-moderate atypical hyperplasia and 5 as showing severe atypical hyperplasia. Three of the latter cases were similarly identified by an analogous cytologic grading; the other two cases had insufficient cytologic samples. The total results in this series of 114 cases support the use of stereotaxic FNA cytology in the diagnosis of these nonpalpable breast lesions, examples of which are illustrated. In particular, it may help to raise the low specificity yielded by mammography alone, which would represent a significant advance for the patient in terms of the accuracy, expediency and reduced cost of diagnosing these lesions.     

Fine needle aspiration cytology of desmoplastic small round cell tumor. A case report.

BACKGROUND: Intraabdominal desmoplastic small round cell tumor (DSRCT) is a recently recognized type of primitive sarcoma characterized by a predilection for young males, a usually very aggressive course and generally unsuccessful therapy. A primitive histologic appearance with prominent desmoplasia and striking divergent multilineage differentiation are well-described morphologic features of this tumor, along with a consistent fusion of the EWS and WT1 genes at the molecular level. The cytologic literature contains only scattered references to this type of neoplasm. Detailed information on the clinical and fine needle aspiration (FNA) biopsy and the immunocytochemical and ultrastructural findings in a patient with DSRCT is presented. CASE REPORT: A 23-year-old male had a firm abdominal mass with multiple secondary lesions of the liver. An FNA biopsy was performed under ultrasonographic guidance. CONCLUSION: FNA of the liver nodules showed cohesive groups of small cells with hyperchromatic nuclei and inconspicuous nucleoli; immunocytochemically vimentin and desmin showed characteristic perinuclear globular positivity. FNA cytology is an effective means of diagnosing deeply located lesions. The cytologic features of DSRCT need to become familiar to pathologists and must be considered in the differential diagnosis of liver metastasis.     

Fine needle aspiration cytologic study of the solitary thyroid nodule. Profile of 308 cases with histologic correlation

The cytologic features and diagnoses of 308 solitary thyroid nodules subjected to fine needle aspiration (FNA) are presented and correlated with the histopathology. The findings reconfirmed the overall utility of FNA cytology in the differentiation of benign from neoplastic lesions and in the specific diagnosis of most types of thyroid lesions. The difficulty in the diagnosis of follicular carcinoma and in its differentiation from follicular adenoma is highlighted. Of note was the finding of Hürthle-cell populations in several types of lesions, which represents a potential diagnostic problem; this potential difficulty was lessened by sampling two or three areas within a nodule, thus obtaining a more truly representative specimen.     

Cementifying fibroma diagnosed by fine needle aspiration cytology. A case report.

A case of cementifying fibroma in the right lateral mandible was diagnosed by fine needle aspiration (FNA) cytology. The aspirate was a cellular specimen composed of clusters of oval and spindle-shaped fibroblasts with no atypical features. These cells were admixed with spherical, calcified structures. A diagnosis of "consistent with benign fibroosseous lesion, suggestive of cementoossifying fibroma" was made, and subsequent histologic examination confirmed this cytologic diagnosis. The clinical, cytologic and histologic findings in the case are presented, and the value of FNA cytology in the diagnosis of jaw lesions is discussed.     

Conventional respiratory cytology versus fine needle aspiration cytology in the diagnosis of lung cancer

The results of 184 fine needle aspiration (FNA) cytologic examinations were compared with the findings of "conventional" respiratory cytology (on sputums, bronchial brushings and bronchial washings) and histology (on biopsy and autopsy samples) and with the medical records. Positive cytologic results were obtained in 6 (10%) of 60 sputums, 17 (21%) of 80 brushings, 16 (19%) of 84 washings and 82 (44%) of 184 aspirates. These positive results were confirmed by biopsy for 6 of 6 sputums, 16 of 17 brushings and 15 of 16 washings. Among the 82 patients with a positive FNA cytology, malignancy was confirmed by lung biopsy in 39 and by autopsy in 2; the cytologic diagnosis was supported by clinical and radiographic findings in all but 1 of the remaining 41 patients. Using transbronchial lung biopsy, autopsy and medical records as final standards, the positive predictive values were 100% for sputum, 94.1% for brushings, 93.0% for washings and 98.6% for FNA samples. The high positive predictive values of FNA and the other cytologic procedures indicate that these diagnostic modalities provide simple, rapid and reliable methods for the diagnosis of lung cancer.     

Fine needle aspiration cytology of parathyroid adenoma. A review of seven cases

The value of fine needle aspiration (FNA) cytology in the diagnosis of parathyroid adenomas was demonstrated by a cytohistologic review of seven cases. The cytologic patterns, which were characterized by numerous, mostly isolated epithelial cells and naked nuclei showing anisokaryosis and multiple nucleoli, were consistent with the histologic findings in this neoplasm, which should be considered in the differential (FNA) diagnosis of masses in the neck region. The only diagnostic problem is its differentiation from follicular thyroid neoplasms.     

Fine needle aspiration cytology of mammary duct ectasia: report of a case with novel cytologic and immunocytochemical findings.

BACKGROUND: Mammary duct ectasia (MDE), or periductal mastitis, is a well-defined clinical entity with a characteristic histopathologic appearance on breast biopsy specimens. However, the cytologic features of MDE have been described only recently in the cytopathology literature, and fine needle aspiration (FNA) cytologic findings are based mainly on a small number of case reports in the English-language literature. Therefore, awareness of this entity and recognition of its cytomorphologic features could aid in a more accurate diagnosis. We report the novel cytologic and immunocytochemical findings on a case of MDE that was confirmed by histologic examination on a subsequent biopsy. CASE: We report the findings of breast FNA cytology in a 50-year-old female with a mammographically and clinically suspicious lesion. Cytology displayed a paucicellular aspirate, typified by a few scattered, cohesive clusters of ductal epithelial cells with mild nuclear atypia and distinct, peripherally located myoepithelial cells. Intermingled within the ductal elements were numerous polygonal cells with abundant, finely vacuolated cytoplasm that were immunoreactive for macrophage-specific antibody, CD68. The background consisted of a variable number of foam cells and negligible amount of blood. CONCLUSION: The current case of MDE demonstrates cytomorphologic features that may pose diagnostic problems, particularly as a consequence of variable cytologic atypia this entity may present on FNA cytology. This diagnostic difficulty is compounded because of the abnormal mammographic and suspicious clinical findings that may be associated with MDE. CD68 immunoreactivity is a useful ancillary tool to verify the histiocytic, rather than epithelial and potentially neoplastic, nature of multivacuolated cells. To the best of our knowledge, there has been no prior reported case of MDE in the English-language literature studied utilizing CD68 antibody. This case report emphasizes that MDE is a heterogeneous entity with diverse cytomorphologic features. FNA cytology in conjunction with immunocytochemistry might permit accurate classification in the proper clinical setting.     

Bronchial brushing cytology features of primary malignant fibrous histiocytoma of the lung. A case report

BACKGROUND: Malignant fibrous histiocytoma (MFH) of the lung is rare. Early diagnosis is very important because of its poor prognosis. Long-term survivors of pulmonary MFH are patients who had surgical resection. When the patient can undergo surgery after a prompt diagnosis, the prognosis improves more than with other therapy. However, it is not easy to establish the diagnosis of thoracic MFH. In general, the small fragments from bronchial or percutaneous transthoracic fine needle aspiration (FNA) biopsies are inadequate for cytologic or pathologic analysis. Bronchial brushing cytology is greatly superior to FNA cytology because one can obtain a large amount of cells. Therefore, bronchial brushing cytology may play a useful role in diagnosis when endobronchial involvement is found. CASE: A 65-year-old female was admitted with a cough, yellow sputum and exertional dyspnea. A chest roentgenogram showed a 12 x 12-cm mass in the left lung field. Bronchial brushing cytology revealed many fibroblastlike, histiocytelike, bizarre and multinucleated giant cells in a background of necrosis. Atypical mitotic figures were also found. The cytologic findings strongly suggested MFH. Although the pathologic findings from FNA biopsy showed storiform clusters structured by pleomorphic, fibroblastlike cells with bizarre nuclei and mitotic figures, the material was too small to diagnose it definitively. Six months later the patient died. An autopsy confirmed the diagnosis of MFH: the typical storiform clusters were composed of many fibroblastlike and histiocytelike cells that were positive for CD68 (PGM1) antibody. CONCLUSION: Bronchial brushing cytology may be a useful method for early, definitive diagnosis of MFH. The presence of pleomorphic, spindle-shaped fibroblastlike and histiocytelike cells with the clusters showing a storiform pattern may permit the diagnosis of MFH.     

Fine needle aspiration biopsy for preoperative workup of pancreatic cystic neoplasms: report of 4 cases

BACKGROUND: Cystic neoplasms of the pancreas comprise a pathologically heterogeneous group of lesions that usually present with similar, nonspecific clinical features. Based on the diagnosis, treatment varies from watchful observation of the lesion to total surgical resection of the pancreas. Therefore the importance of a precise and accurate diagnosis on fine needle aspiration (FNA) biopsy cannot be overemphasized from the patient management standpoint. There is debate regarding the accuracy of FNA diagnosis of cystic lesions of the pancreas. We report 4 cases and review the literature to explore and highlight the cytologic findings and diagnostic pitfalls that may help the cytopathologist accurately distinguish mucinous cystic neoplasm (MCN), intraductal papillary mucinous neoplasm (IPMN), serous cystadenoma (SCA) and ductal adenocarcinoma (DAC). CASES: We present 4 cases of patients with abdominal masses who underwent either computed tomography (CT)-guided or endoscopic ultrasound (EUS)-guided FNA biopsy as preoperative workup. Based on the cytologic diagnosis, the patients underwent surgery. CONCLUSION: Our cases illustrate the cytologic criteria that help the cytopathologist distinguish among MCN, IPMN, SCA and DAC. Correlation with clinical and radiologic findings is strongly advocated for accurate diagnosis. We describe the diagnostic pitfalls frequently encountered in these cases and how to avoid them.