Midline carcinoma expressing NUT in malignant effusion cytology.

Nuclear protein in testis (NUT) midline carcinoma (NMC) is a rare and aggressive subset of poorly differentiated squamous cell carcinoma that is defined by t(15,19) and typically presents in the midline structures of the head, neck, and mediastinum. We report two cases of NMC that presented uniquely with malignant pleural and pericardial effusions including one with cardiac tamponade at presentation. The first case is of a 25-year-old male patient who presented with progressive dyspnea associated with palpitations and dizziness on standing, found to have large bilateral pleural effusions. The second case is of a previously healthy 29-year-old male patient who presented with progressive dyspnea, cough with expectoration, and a large right lower neck mass of 3 months onset, and a large left pleural effusion and left lung infiltrate on imaging studies. Both cases showed malignant cells on cytology suggestive of poorly differentiated carcinoma. Subsequent histopathological and immunochemistry studies were consistent with the diagnosis of NMC. Both patients had a rapid decline in status and suffered comorbidities secondary to their carcinoma, inevitably leading to their death. It is important to consider NUT midline carcinomas can present in a variety of clinical scenarios, and it is important to consider in the differential diagnoses when evaluating malignant effusion cytology. Utilization of ancillary testing with a broad immunostain profile including NUT studies, as well as fluorescent in-situ hydridization (FISH) studies are helpful and necessary in making the appropriate diagnosis.

The impact of atypia/follicular lesion of undetermined significance and repeat fine-needle aspiration: 5 years before and after implementation of the Bethesda System.

BACKGROUND: Limited studies have examined the impact of the Bethesda System for Reporting Thyroid Cytopathology (BSRTC) and specifically the category of atypia or follicular lesion of undetermined significance (AUS/FLUS). We studied their effects on reporting rates, subsequent management, and surgical outcome over a 10-year period, 5 years before and after implementation of the BSRTC. METHODS: A retrospective review of thyroid fine-needle aspiration (FNA) reports from 2003 to 2012 was performed. Diagnoses made before BSRTC were reclassified into the most appropriate category. Repeat FNA results for all AUS/FLUS cases were recorded. Surgical follow-up results were matched by side and size of the targeted nodule. Incidental microcarcinomas were not considered "malignant" on excision. Malignancy rates were calculated based on excision and by all aspirated specimens. RESULTS: Initial AUS/FLUS cases increased from 3% to 7% (P = .001) with implementation of the BSRTC. The nondiagnostic rate decreased from 19% to 10% (P = .026). Differences in malignancy rates before and after implementation of the BSRTC were not significant for all diagnostic categories. More repeat FNAs and fewer surgical excisions were performed after an initial AUS/FLUS diagnosis. Repeat FNA reclassified 56% of AUS/FLUS cases into a definitive category. The malignancy risks for AUS/FLUS plus benign and AUS/FLUS plus AUS/FLUS repeat FNAs were elevated compared with single benign and AUS/FLUS diagnoses. CONCLUSIONS: AUS/FLUS cases are increasing with the implementation of the BSRTC. Given the potential increase in repeat FNAs as a result, it may be important to alert the clinician regarding the elevated malignancy risk of a benign or AUS/FLUS diagnosis associated with a prior AUS/FLUS finding.

Significance of the diagnostic categories "atypical" and "suspicious for malignancy" in the cytologic diagnosis of solid pancreatic masses.

Endoscopic ultrasound guided (EUS) fine-needle aspiration (FNA) investigation of solid pancreatic lesions has been shown to have good sensitivity and specificity. Many lesions can be definitely classified as benign or malignant but some can only be cytologically classified as "atypical" or "suspicious for malignancy". Risk for malignancy in these indeterminate categories has not been well categorized. The cytology records of four University Medical centers were searched for all EUS guided FNAs of solid pancreatic lesions. All cases with a diagnosis of "atypical", or "suspicious for malignancy" were selected for analysis when histologic biopsy or over 18 months clinical follow-up was available. Two hundred and ninety-two cases with a diagnosis of "atypical" or "suspicious for malignancy" and adequate follow-up were obtained from the combined data of the four institutions. The percentage malignant for the categories "atypical" and "suspicious for malignancy" were 79.2 and 96.3%, respectively. If the category "atypical" was classified as benign and "suspicious for malignancy" was classified as malignant, the resulting positive predictive value was 96.3 (95% CI: 92.6-98.5) and the negative predictive value 20.8 (95% CI: 13.4-30.0). The categories of "atypical" and "suspicious for malignancy" stratify risk for malignancy in a fashion, which may aid in patient counseling and selection of follow-up protocols. Classification of "suspicious for malignancy" as malignant optimizes diagnostic sensitivity and specificity.

Juvenile granulosa cell tumors: immunoreactivity for CD99 and Fli-1 and EWSR1 translocation status: a study of 11 cases.

The accurate diagnosis of a juvenile granulosa cell tumor (JGCT) can be challenging, as these neoplasms often exhibit morphologic features that overlap other ovarian neoplasms. In addition, the immunohistochemical profile exhibited by JGCT is fairly nonspecific and typically includes reactivity for CD99. Recently, we noted that JGCTs can show immunohistochemical expression of Fli-1, a transcription factor expressed by Ewing sarcoma, a neoplasm that is occasionally in the differential diagnosis of JGCT. We evaluated a series of JGCTs to determine whether Fli-1 is commonly expressed by these tumors and whether they demonstrate chromosomal arrangements in EWSR1. Cases diagnosed as JGCT (n=11) were immunohistochemically evaluated for expression of Fli-1 and CD99. Fluorescence in situ hybridization was performed on all cases to search for chromosomal rearrangements in EWSR1. All 11 of our cases exhibited positive immunohistochemical staining for Fli-1 and CD99. None of the cases demonstrated rearrangement in EWSR1 by fluorescence in situ hybridization. In cases of JGCT that cannot be reliably distinguished from Ewing sarcoma based on morphology and immunohistochemistry alone, fluorescence in situ hybridization testing for EWSR1 rearrangements seems to be a useful diagnostic adjunct for their separation.

Hints to the diagnosis of mixed acinar-endocrine carcinoma on pancreatic fine-needle aspiration: avoiding a potential diagnostic pitfall.

BACKGROUND: Mixed acinar-endocrine carcinoma (MAEC) is a rare mixed tumor of the pancreas defined by both acinar and endocrine cell differentiation. CASE: We present 2 cases of MAEC initially diagnosed as pancreatic endocrine neoplasm on fine-needle aspiration. Both patients were male, aged 51 and 75 years, and presented with 16-mm and 6-mm pancreatic masses, respectively. Aspirates showed loose aggregates and dispersed single plasmacytoid cells with moderate nuclear size variation, slightly irregular nuclear contours, fine to coarsely granular chromatin, occasional prominent nucleoli, and scant to moderate finely granular cytoplasm. Rare mitotic figures and pyknotic forms were noted in one of the cases. Endocrine differentiation was confirmed by immunocytochemistry which led to an initial diagnosis of pancreatic endocrine neoplasm. Trypsin and lipase immunocytochemistry were later obtained, confirming a component of acinar cell differentiation. Findings were confirmed on surgical excision. CONCLUSION: Because of their potentially more aggressive clinical course and different therapeutic implications, MAECs are an important consideration in the differential diagnosis of pancreatic neoplasms. Certain cytomorphologic features and immunocytochemical markers of acinar cell differentiation may be helpful in raising the possibility of MAEC on cytology.

Metastatic disease to the pancreas documented by endoscopic ultrasound guided fine-needle aspiration: a seven-year experience.

The study was performed to determine the frequency and origin for metastatic disease to the pancreas as found in an endoscopic ultrasound directed fine-needle aspiration series. The records of the Departments of Pathology at the University of Utah School of Medicine and the David Geffen School of Medicine were electronically searched for all fine-needle aspirates obtained from pancreatic masses between January 1, 2002 and March 31, 2010. All cases with a diagnosis of metastatic disease were reviewed and whenever possible correlated with subsequent resection specimens. A total of 17 metastatic malignancies to the pancreas were detected in pancreatic FNAs representing 0.73% of all cases. Primaries included eight renal cell carcinomas, one medullary carcinoma of the thyroid, four lymphomas, one alveolar rhabdomyosarcoma, one squamous cell carcinoma derived from the esophagus, and a second squamous cell carcinoma originating from a lung primary and a small cell carcinoma of the lung. Metastatic renal cell carcinoma was the most frequent metastasis to the pancreas representing 47% of metastatic lesions detected by FNA. The metastatic deposits could be detected in the pancreas as many as 10 years following the original diagnosis and resection of the renal cell carcinoma.

Fine-needle aspiration biopsy as an adjunct to the diagnosis of a rare adnexal tumor of hair follicle origin: trichoblastoma.

Fine-needle aspiration biopsy (FNAB) is a technique used increasingly for the investigation of primary and metastatic cutaneous tumors. Trichoblastoma is a rare benign skin appendage tumor of hair germ origin. We report the diagnosis by FNAB of a rare giant subcutaneous tumor, trichoblastoma, from an 81-yr-old woman with a subcutaneous mass in the interscapular area of her back. The cytologic characteristics of the tumor are discussed in detail in this report. The findings have been compared with the histologic features of the tumor after surgical excision. We have characterized several distinctive cytologic features that may aid in the diagnosis of this rare neoplasm. While most reported cases have been diagnosed from surgical excisional biopsy specimens, FNAB may also be a valuable tool for the accurate diagnosis of trichoblastoma in the proper clinical context.

Simultaneous occurrence of medullary and papillary carcinoma of the thyroid gland identified by fine needle aspiration. A case report.

BACKGROUND: Fine needle aspiration (FNA) diagnosis of simultaneous medullary and papillary thyroid carcinoma in independent thyroid lobes is exceedingly rare. CASE: A 36-year-old female presented with a one-month history of dysphagia. Thyroid ultrasound revealed a multinodular goiter. She was clinically and biochemically euthyroid. FNA of the right thyroid nodule was consistent with medullary carcinoma, and FNA of the left thyroid lobe was consistent with papillary carcinoma. Immunohistochemistry revealed strong calcitonin and CEA positivity in the right lobe and lack of staining in the left lobe. Conversely, staining for thyroglobulin was negative on the right lobe and positive on the left lobe. CONCLUSION: The patient developed tumors in separate lobes of the thyroid. Immunoreactivity of calcitonin, CEA and thyroglobulin made a sharp distinction between the two tumors. Therefore, we conclude that these tumors were not linked by either embryology or genetics.