Percutaneous image-guided fine-needle aspiration of peritoneal lesions

Fine-needle aspiration (FNA) is a widely accepted technique for the initial tissue diagnosis of a variety of lesions arising within retroperitoneal and intraabdominal viscera. Fear of complications secondary to perforation of the bowel wall has limited the use of FNA in the diagnosis of gastrointestinal and peritoneal masses. A variety of primary and secondary neoplasms involving the peritoneum may present as multiple nodules, as masses, or as diffuse involvement of the peritoneum. When these lesions are associated with mass lesions or areas of significant peritoneal thickening, they become amenable to percutaneous image-guided FNA. We report on our experience with a series of 23 peritoneal lesions investigated by FNA for which subsequent histologic confirmation was available in 19, along with an additional 4 cases without histologic confirmation. One to four passes were made into each lesion, and immediate assessment for adequacy was performed by a cytopathologist in all cases. All 17 cases with a specific cytologic diagnosis and histologic confirmation represented either primary or metastatic neoplasms (5 gastrointestinal stromal tumors, 4 metastatic melanomas, 2 mesotheliomas, 1 lymphoma, 1 example of Kaposi's sarcoma, 1 serous papillary carcinoma of ovarian origin, 1 mucinous adenocarcinoma of ovarian origin, 1 intraabdominal desmoplastic small-cell tumor, and 1 solitary fibrous tumor of the peritoneum). In an additional 4 cases, the aspirates were judged as insufficient for diagnosis, with the smears containing only blood and benign mesothelial cells and/or inflammatory cell elements. These four smears were associated with both neoplastic and nonneoplastic lesions. Surgical confirmation was obtained in only 2 of these cases (1 metastatic melanoma and 1 example of omental and peritoneal involvement by an ovarian adenocarcinoma). Two cases without histologic confirmation were associated with clinically confirmed metastases. In our series, no acute or chronic postprocedural complications were identified, indicating that FNA in this setting is a safe technique. Accurate cytologic diagnosis was achieved in 74% of cases. The overall insufficiency rate was 26%.     

Cytodiagnosis of primary lymphoma of bone on fine-needle aspiration cytology specimens: review of 25 cases

Diagnosis of nodal lymphomas on fine-needle aspiration (FNA) cytologic specimens has been well established. However, cytodiagnosis of primary lymphoma of bone has not been well documented because of its rarity. We undertook a retrospective study of 25 cases of FNA cytologic specimens of primary lymphoma of bone. The slides were available for review in 20 cases; each case was evaluated with 15 cytologic features in conjunction with immunophenotyping and available surgical materials. Three diagnostic categories were assigned, including nondiagnostic (4/16%), suspicious (3/12%), and malignant (18/72%). Among the 18 malignant lymphoma, all were diagnosed on the basis of cytologic materials together with immunocytochemistry, except that two cases also relied on the cell blocks. The nondiagnostic and suspicious cases were subsequently confirmed to be malignant lymphoma on the surgical core biopsies. Of the 25 cases, 23 cases were large B-cell lymphoma, one follicular lymphoma large cell type, and one small lymphocytic lymphoma. False-positive or false-negative cases were not present in this study series. In conclusion, the vast majority of primary lymphoma of bone can be accurately diagnosed and classified on FNA cytologic specimens in conjunction with immunocytochemistry. The nondiagnostic and suspicious categories can be further reduced or eliminated by improving FNA techniques or by recommendation of surgical core biopsies together with other techniques such as flow cytometry and molecular analysis.     

Diagnostic value of telomerase expression in breast fine-needle aspiration biopsies

Fine-needle aspiration biopsy (FNAB) of breast is a minimally invasive sampling procedure with a proven value in the initial evaluation of patients with palpable breast lesions. FNAB is a simple, cost-effective, and relatively nontraumatic procedure that has replaced open surgical biopsy in majority of academic institutions across the world. There are, however, inherent limitations in the ability of FNAB to reliably diagnose small percentage of cases that are difficult to diagnose by cytomorphology alone and require excisional biopsy. This shortcoming may be minimized if the morphology can be complemented by a reliable diagnostic adjunct. This retrospective study was designed to assess the added value of telomerase immunostain in interpretation of breast FNABs. Telomerase is a ribonucleoprotein enzyme that has been shown to be activated in different malignant tumors, including breast cancer. Immunocytochemical detection of this molecular marker on cytologic smears and cellblocks may be helpful for interpretation of FNAB specimens. In our retrospective study, we found that 56% of the malignant breast cases (28/50) showed positive telomerase immunostaining while only 4% of the negative cases (2/50) stained with telomerase (positive predictive value: 93%, negative predictive value: 69%). Expression of telomerase on highly suspicious breast fine-needle aspirations may upgrade the diagnosis to malignancy. However, a negative telomerase cannot exclude the possibility of carcinoma.     

Diagnostic impact of core-needle biopsy on fine-needle aspiration of non-Hodgkin lymphoma

We retrospectively reviewed 74 fine-needle aspiration (FNA) cases of presumptive non-Hodgkin lymphoma (NHL). All the cases had cytology and core-needle biopsy and 53 cases had concurrent flow cytometric analysis. FNA (cytology and flow cytometry) and core-needle biopsy were evaluated independently. FNA was diagnostic of diffuse large B-cell lymphoma (DLBL) in 25% (13/53) of cases and small B-cell NHL in 15% (8/53) of cases, whereas core-needle biopsy was diagnostic of DLBL in 37% (27/74) of cases and small B-cell NHL in 8% (6/74) of cases. Subclassification of small B-cell NHL was reached in 3/6 cases by core-needle biopsy. Insufficient cases were observed in both FNA (47%; 25/53) and core-needle biopsy (28%; 21/74) groups. With the combination of FNA and core-needle biopsy, diagnostic cases of DLBL increased to 43% (32/74) and insufficient samples were reduced to 16% (12/74). There was no clear advantage in the diagnosis and classification of small B-cell NHL by adding core-needle biopsy to FNA (14%; 10/74). We conclude that core-needle biopsy is a useful adjunct to FNA in the diagnosis of DLBL and shall be encouraged. In small B-cell NHL, core-needle biopsy does not add to the diagnostic ability of FNA. Cases insufficient for diagnosis may be seen in both core-needle biopsy and FNA. A combined approach reduces the number of insufficient cases and is recommended in routine FNA practice.     

Columnar cell lesions: fine-needle aspiration biopsy features

Columnar cell lesions (CCLs) have been described histologically. Frequently, they are noted in biopsies performed for calcifications and are associated with an increased risk of malignancy in the presence of atypia. We sought to characterize the cytological features of CCLs in fine-needle aspirations (FNAs). Twenty FNAs with subsequent histology diagnoses of CCL without carcinoma were reviewed retrospectively. Eighteen of 20 cases were classified as "atypical" on cytology; they had cohesive three-dimensional clusters of enlarged polygonal epithelial cells intermixed with myoepithelial cells in the centers and palisading columnar cells peripherally. Five of these had cytological or architectural atypia on subsequent biopsies, but no significant differences were noted among the 18 aspirates. Calcifications (2/18), snouts (9/18), and bipolar nuclei (11/18) were also identified. The remaining 2/20 FNAs were interpreted as negative because of scant cellularity. In conclusion, CCLs have characteristic cytological traits, and because they may be associated with carcinoma, their recognition is important.     

Intravascular papillary endothelial hyperplasia of the neck masquerading as malignancy on fine-needle aspiration cytology

Papillary endothelial hyperplasia (PEH) is an exuberant, usually intravascular endothelial proliferation that, in many respects, mimics angiosarcoma. A case of PEH originally suggestive of embryonal carcinoma by fine-needle aspiration is presented. A 12-year-old boy presented with a palpable mass on the right side of the neck. The mass was subsequently aspirated. Cytopathologic features showed cohesive sheets of polygonal pleomorphic cells with vesicular nuclei and prominent multiple nucleoli in a hemorrhagic background. Cytologic findings were strongly suggestive of metastatic embryonal carcinoma. There was no evidence of a primary lesion. After the mass was surgically excised, the pathologic findings showed PEH. A retrospective immunocytochemical stain for factor VIII-related antigen on a destained ethanol-fixed smear confirmed the endothelial nature of the polygonal cells. A vascular lesion should be considered, especially when atypical polygonal cells in a hemorrhagic background are present, as they were in this case.     

Diagnostic role of fine-needle aspiration of pancreatic allograft to detect rejection

The purpose of this study was to assess whether the same principles to evaluate renal transplant by fine-needle aspiration (FNA) for rejection could be applied to pancreatic allograft. Between 1996-1998, 25 ultrasound-guided FNAs on 13 patients with pancreatic allograft were performed and ThinPrep made. The percentage of lymphocytes, lymphoblasts, monocytes, eosinophils, plasma cells, immunoblasts, and macrophages were calculated. Simultaneous peripheral smear was obtained and "total corrected increment" score calculated. Subsequent core biopsy was available in six patients. A total of seven FNAs on three patients were inadequate because of insufficient epithelial cells. No evidence of rejection reported in nine patients was confirmed on biopsy in five patients. One patient reported as suspicious later showed rejection on biopsy. Thus, FNA may be used to monitor the graft status with faster turnaround times. Rejection may be a focal process and FNA may be used for sampling multiple sites. Cytologic diagnosis fairly accurately detects early rejection. Core biopsies are warranted in unsatisfactory specimens and when FNA is suspicious for rejection.     

Malignant biphasic pleural mesothelioma metastatic to the liver diagnosed by fine-needle aspiration

As malignant pleural mesotheliomas are most often rapidly fatal, distant metastases are rarely detected. Here, we report a unique case in which the diagnosis of metastatic pleural mesothelioma was made via cytologic examination of a fine-needle aspiration (FNA) of the liver. Recognition of the cytomorphologic features inherent to mesothelioma cells on FNA material may become important for proper patient management. To the best of our knowledge, the diagnosis of malignant pleural mesothelioma metastatic to the liver made by FNA has not been previously documented.     

Melanoma with cartilaginous differentiation: Diagnostic challenge on fine-needle aspiration with emphasis on differential diagnosis

Fine-needle aspiration (FNA) is a minimally invasive, fast, and accurate diagnostic method for the evaluation of patients with locally recurrent or distant metastases of malignant melanoma. In the vast majority of cases, the diagnosis is straightforward with the characteristic cytologic features well documented in the literature. Divergent differentiation (chondroid, neural, myofibroblastic, and osteocartilagenous) in a melanoma is rare and can potentially create diagnostic challenges if the evaluator is unaware of the same. We report a case of a 46-year-old female with a history of primary anal melanoma who presented with a groin mass. The FNA of the groin mass showed a neoplasm rich in chondroid matrix and raised the possibility of a second primary mesenchymal neoplasm rather than metastasis from the patient's known primary anal melanoma. A review of the histologic features of the anal melanoma showed divergent chondroid differentiation in the anal melanoma with the metastatic deposit in the groin exhibiting extensive chondroid differentiation. The differential diagnostic considerations are discussed.     

Reliability of fine-needle aspiration biopsy in the initial diagnosis of soft-tissue lesions

We retrospectively reviewed fine-needle aspiration biopsy (FNAB) specimens of 301 soft tissue lesions of the extremities and trunk. Final diagnoses were 137 benign and 86 malignant neoplasms and 78 nonneoplastic lesions. Of the 301 FNAB samples, 279 (93%) were adequate for cytologic diagnosis. The adequate FNAB specimens were initially grouped into three broad categories: benign (197 cases), malignant (57 cases), and suspicious for malignancy (25 cases). Sensitivity and specificity for diagnosis of a malignant lesion were 92% and 97%, respectively. The specimens were cytomorphologically classified into nine categories: small round (14 cases), spindle cell (77 cases), epithelioid/polygonal (16 cases), pleomorphic (29 cases), myxoid (19 cases), lipomatous (37 cases), epithelial (23 cases), inflammatory lesions (28 cases), and others (36 cases). Specific FNAB diagnoses were correct in 151 of 279 cases (54%) in combination with clinical and radiologic findings. FNAB is a valuable technique for the primary diagnosis of soft-tissue lesions.     

Cystic change in metastatic lymph nodes: a common diagnostic pitfall in fine-needle aspiration cytology

Fine-needle aspiration cytology (FNAC) of cystic metastases is a challenging diagnostic category and has been investigated in a limited number of malignancies and sites. The present study retrospectively reviewed 1,211 FNAC of superficial masses, including lymph nodes (1,102 aspirates), benign cystic lesions (64 aspirates), and lymphocysts (45 aspirates) with the aim of determining the tumors that cause cystic change in metastases. Cytology results from 1,102 lymph node aspirations were suspicious or positive for malignancy in 541 specimens (49.1%), benign in 230 (20.9%), and unsatisfactory in 331 (30%). There were 28 malignant aspirates demonstrating cystic change (5.2%). The tumor type that most frequently caused cystic change was thyroid papillary carcinoma (42.8% of cases), followed by squamous cell carcinoma (primary in the head and neck region 30.8% and in the skin 24%), tumors of unknown origin (6.3%), serous papillary carcinoma of the ovary or endometrium (4.8%), and malignant melanoma (2.1%). Cystic change was observed most commonly in the head and neck region lymph nodes (60%). The most challenging lesions to assess using FNAC were metastatic lymph nodes showing cystic change, accounting for six of the 16 false-negative diagnoses and one false-positive diagnosis. The results of this study suggest that cystic change in metastatic lymph nodes occurs in certain types of tumors and is an important cause of diagnostic error. FNAC should be repeated in case of suspicious hypocellular cystic aspirations, especially in patients with known malignancy.     

Spindle-cell lesions of the liver: diagnosis by fine-needle aspiration biopsy

Rarely, spindle-cell lesions in liver fine-needle aspiration biopsies (FNABs) are encountered. A retrospective review of our experience with lesions that are mesenchymal in origin or appearance was undertaken to elucidate the frequency and spectrum of these lesions. Image-guided liver FNABs performed over a 3-year period (n = 585) at our institution (1996-1998) were retrospectively evaluated. Cytologic smears, cell block preparations, and clinical follow-up of lesions with spindle-cell morphology were reviewed. Twenty-nine of 585 cases were of spindle-cell morphology (5%). Hemangiomas (n = 12, 41%) and metastatic sarcomas (n = 6, 21%) comprised the largest categories, followed by granulomatous inflammation (n = 3, 10%). Other cases included primary angiosarcoma and fibrolamellar hepatocellular carcinoma. The most frequent spindle-cell liver lesion encountered is hemangioma, followed by metastatic leiomyosarcoma and granulomatous hepatitis. Awareness of diagnostic possibilities, special attention to specimen adequacy, and use of ancillary procedures can maximize diagnostic yield.     

Distribution of subtypes of metastatic renal-cell carcinoma: correlating findings of fine-needle aspiration biopsy and surgical pathology

Clear-cell (CRCC), papillary (PRCC), and chromophobe (CHRCC) renal-cell carcinoma (RCC) are the three most frequent subtypes of RCC. The rate and distribution of their metastatic lesions have not been well studied in cytopathological materials. Sixty-two fine-needle aspiration biopsy cases of metastatic RCC were studied and correlated with surgical pathology of RCCs with and without metastasis. Special stains for glycogen and immunostaining for cytokeratins, vimentin epithelial membrane antigen (EMA), and carcinoembryonic antigens, and electron microscopic studies were performed. Fifty-nine cases of CRCC and three of PRCC subtypes were retrieved from the cytopathology files at the Ottawa Hospital in a period of 10 years. Of these cases, 10 metastatic CRCC and one metastatic PRCC were diagnosed prior to the diagnosis of the primary tumor. CHRCC and sarcomatoid RCC were not represented in cytopathological specimens. CRCC displayed characteristic filmy cytoplasm and nuclei with prominent nucleoli. PRCC was characterized by dense cytoplasm, large nuclei with prominent nucleoli, and papillary architectures. In addition, all RCCs were characterized by the presence of glycogen and the absence of mucin by using histochemical techniques and electron microscopic studies and positive reactivity for cytokeratins (CK) and vimentin (VIM). In the same period, there were a total of 380 patients with RCC divided into 310 CRCCs, 55 PRCCs, and 15 CHRCCs associated with metastases in 142, 9, and 1 case, respectively. CRCC is by far the most common subtype found in metastases sampled in cytopathology. PRCC, CHRCC, and sarcomatoid RCC were underrepresented. Awareness of this propensity of RCC and the characteristic cytopathological, histochemical, immunohistochemical, and ultrastructural features are helpful in the diagnosis of metastatic RCC.     

The role of endoscopic ultrasound and endoscopic ultrasound-guided fine-needle aspiration in distinguishing pancreatic cystic lesions

Distinguishing mucinous from nonmucinous cystic lesions of the pancreas often constitutes a diagnostic dilemma. The clinical management differs between such lesions; therefore it is important to make an accurate preoperative diagnosis. Various centers have reported conflicting results regarding their ability to detect mucin-producing neoplastic cells and appropriately reach a diagnosis based on endoscopic ultrasound (EUS) guided FNA. The aim of this study is to assess the ability of EUS-FNA cytology to diagnose and differentiate mucinous from nonmucinous pancreatic cystic lesions. We reviewed records of patients who underwent EUS of pancreatic cystic lesions. If FNA was performed and mucinous neoplasm was suspected, aspirate was evaluated for cytomorphology and presence of mucin. FNA results were compared to final histologic diagnosis if surgery was performed.Cytologic diagnosis was provided for 28/30 (93%). By comparing EUS-FNA diagnoses with final surgical pathology, FNA accurately diagnosed in 10/11 cases with sensitivity and specificity for detection of malignancy of 100 and 89, respectively, while the accuracy for identification of mucinous cystic neoplasms was 100%. Our results indicate that in the appropriate clinical and imaging setting, EUS-FNA cytology with analysis for mucin production by tumor cells is an important test in distinguishing pancreatic cystic lesions and guiding further management.     

Utility of fine-needle aspiration in the diagnosis of primary osteosarcoma

Fine-needle aspiration (FNA) is a reliable, safe, and cost-effective procedure with a well-established role in the diagnosis of various solid tissue neoplasms. The role of FNA in the diagnosis of primary bone tumors, including osteosarcoma (OGS), is controversial and has yet to be established. We reviewed our experience with the use of FNA as a diagnostic technique over the past 8 yr at our institution. Diagnosis was conclusive in 26 (65%) of 40 patients, 18 of whom went to neoadjuvant therapy and/or resection based solely on the FNA interpretation of either "high grade sarcoma" or "osteosarcoma." Of the remaining 14 (25%) patients, 12 had inconclusive diagnosis and two (5%) were false-negatives. An inconclusive diagnosis was most likely to be an inadequate or paucicellular aspirate, seen in six (15%) patients. An additional six patients had variants of osteosarcoma (four chondroid, one "giant cell rich," one parosteal) that made definitive diagnosis impossible. The two that were incorrectly classified were diagnosed as fracture callus and plasmacytoma. FNA is an accurate and cost-effective tool for the initial diagnosis of primary osteosarcoma with a sensitivity of 65% and accuracy of 95%. Inconclusive diagnoses are likely to be due to insufficient sample cellularity or the presence of OGS variant. In our experience, FNA is sufficient to provide the diagnosis of OGS prior to definitive treatment when interpreted in conjunction with imaging studies and clinical findings. In those cases where FNA fails to yield a diagnostic sample, a traditional biopsy can be performed.     

Choroidal metastasis from an occult primary diagnosed by fine-needle aspiration: a case report

Choroidal masses are rarely the first presentation without the primary tumor being discovered. We described fine needle aspiration biopsy (FNAB) of a choroidal mass for diagnosis and determining the primary site. The patient, a 50-year-old Caucasian male without significant past medical history, presented with visual disturbances and headaches. Intraoperative ocular FNA was performed which was sparsely cellular showing a few loosely cohesive sheets and singly arranged epithelial cells with moderate amount cytoplasm, round large nuclei and prominent nucleoli. Immunohistochemical stainings on the cell block material showed positive staining of cytokeratin and negative staining of melanoma markers. The diagnosis of metastatic adenocarcinoma was rendered. During clinical follow up studies, the patient was found to have a PET positive lung nodule and multiple visceral metastasis.     

Cystic lesions of the salivary glands: cytologic features in fine-needle aspiration biopsies

A variety of neoplastic and nonneoplastic lesions of the salivary glands have a predominantly cystic architecture. Fine-needle aspirates of these lesions yield watery or mucoid material, frequently of low cellularity. Such aspirates may be obtained from mucus retention cysts, lymphoepithelial cysts, cystadenomas, Warthin's tumors, cystic pleomorphic adenomas, low-grade mucoepidermoid carcinomas, cystadenocarcinomas, and examples of polycystic disease of the parotid gland. The cellular component within the fluid obtained from these lesions may be exceedingly scant or absent, making cytologic diagnosis difficult and, at times, impossible. We studied a series of 56 cystic lesions of the salivary glands, including 38 Warthin's tumors, 6 benign cysts, 2 lymphoepithelial cysts, 5 low-grade mucoepidermoid carcinomas, 1 cystic pleomorphic adenoma, 2 cystadenomas, and 2 cystadenocarcinomas. Careful attention to the cellular elements present often allowed definitive cytologic diagnosis, with an overall accuracy rate of 84%. The presence of atypical squamous metaplasia in oncocytic lesions was a significant cause of false-positive diagnoses of carcinoma (4 cases, 7%). Aspirates of low-grade mucoepidermoid carcinoma may contain no epithelial cells and result in false-negative diagnoses (1 case, 2%).     

The role of flow cytometric immunophenotyping in improving the diagnostic accuracy in referred fine-needle aspiration specimens

Flow cytometric (FCM) immunophenotyping has an important role in the diagnostic work up of fine-needle aspiration (FNA) specimens obtained from lymphoid lesions. The objective of the present study was to evaluate the feasibility of this method with respect to referred FNA specimens. One hundred and two FNA specimens referred to our laboratory for FCM analysis during the last 3 years were studied. Specimens were sent, accompanied by cytological smears, from 11 distant hospitals by ordinary mail. The evaluation of potential B-cell monoclonality, the main diagnostic issue to be resolved using FCM, was possible in 86 of these 102 cases. The remaining 16 samples could not be analyzed or adequately interpreted because of sparse or necrotic material. A monoclonal B-cell population was found in 17/86 satisfactory cases, of which 16 were histologically confirmed. Eight cases contained cells positive for the epithelial marker Ber-EP4 and were diagnosed accordingly as carcinomas. FCM analysis of specimens obtained with a clinical question of Hodgkin lymphoma or T-cell lymphomas did not yield definitive data. The time lapse between sampling and analysis (12-84 hr) did not affect the results. This probably was due to the fact that all aspirates were taken in Roswell Park Memorial Institute (RPMI) cell medium, supplemented with 50% fetal calf serum. In conclusion, this retrospective study establishes that it is possible, in the majority of cases, to refer FNA material for FCM immunophenotyping by mail, and that results regarding B-cell clonality in the case of small-cell lymphomas are reliable also after a transportation period of 3-4 days. Carcinoma may be similarly diagnosed and a diagnosis of lymphoma may be excluded in reactive proliferations. Cases with only a few atypical cells or specimens from patients suspected of having Hodgkin lymphoma or T-cell lymphomas are not suitable for analysis by FCM.