Kathryn Dyhdalo

Pulmonary Histologic Changes in Marfan Syndrome A Case Series and Literature Review

Marfan syndrome is one of the most common connective tissue diseases and may manifest with a range of symptoms and pathologic changes. We present a retrospective series of 5 cases of patients with Marfan syndrome and pulmonary pathology. Patients were young to middle-aged adults with absent or minimal smoking histories and absent to severe clinical pulmonary symptoms. Tissue specimens were obtained from the surgical pathology and autopsy services. Histologic examination revealed a consistent pattern of distal acinar emphysema in all patients. Comparisons are made with other cystic-type diseases of the lung that may histologically mimic this pattern. This is the largest contemporary series of histologic pulmonary involvement of Marfan syndrome and the first to describe this pattern of pulmonary changes in this patient population.

Assessment of cellularity, genomic DNA yields, and technical platforms for BRAF mutational testing in thyroid fine-needle aspirate samples.

BRAF mutation V600E (substitution Val600Glu) is a molecular signature for papillary thyroid carcinoma (PTC). Testing for BRAF mutation is clinically useful in providing prognostic prediction and facilitating accurate diagnosis of PTC in thyroid fine‐needle aspirate (FNA) samples.

Immunoarchitectural patterns of germinal center antigens including LMO2 assist in the differential diagnosis of marginal zone lymphoma vs follicular lymphoma.

OBJECTIVES To examine the immunoarchitectural patterns of the germinal center (GC)-associated markers CD10, BCL6, and LMO2 and their utility in the differential diagnosis of marginal zone lymphoma (MZL) vs follicular lymphoma (FL). METHODS Forty-two cases of MZL involving lymph nodes and 88 cases of FL were examined. RESULTS Interfollicular staining for GC markers was uncommon in MZL but common in FL, including BCL2-positive and BCL2-negative cases. Two atypical patterns of intrafollicular GC staining were identified that were more common in MZL than in FL. CONCLUSIONS Staining for LMO2 in addition to CD10 and BCL6 facilitates the detection of a GC phenotype in FL. Lymph nodes involved by MZL frequently show characteristic alterations of GC immunoarchitecture. Recognizing these altered patterns assists in the distinction between MZL and FL.

Endobronchial ultrasound‐guided fine‐needle aspiration cytology of bronchial low‐grade mucoepidermoid carcinoma: Rapid on‐site evaluation of cytopathologic findings

Bronchial mucoepidermoid carcinoma (MEC) is rare, comprising about 0.2% of primary lung tumors. Endobronchial ultrasound (EBUS) guided fine‐needle aspiration (FNA) cytology is an integral tool in the diagnosis and staging of malignant lung tumors. Rapid on‐site evaluation (ROSE) has been proven useful as a guide for assessing the adequacy and accuracy of the FNA samples. Therefore, comprehensive knowledge of diagnostic cytomorphologic findings of MEC is critical for ROSE.

Cystic pancreatic schwannoma diagnosed by endoscopic ultrasound-guided fine needle aspiration: DOXTADER et al.

A 78-year-old woman with chronic lymphocytic leukemia underwent imaging studies for evaluation of progressive disease. A cystic pancreatic mass was incidentally detected on abdominal computed tomogram (CT) scan. The lesion was further evaluated by magnetic resonance imaging (MRI), which showed a unilocular cyst in the posterior body of the pancreas measuring 1.4 × 1.3 cm. Endoscopic ultrasound examination was performed and demonstrated a 1.7 cm pancreatic cyst in the posterior portion of the pancreatic body, with a solid component and suspected nodular internal enhancement (Figure 1). The cystic portion was unilocular and without septae. The lesion did not appear to communicate with the main pancreatic duct. Two passes were made with a 22-gauge needle using a transgastric approach; 0.1 mL of opaque, white fluid was collected in CytoLyt® solution and submitted to the cytopathology laboratory, where a ThinPrep slide and CellientTM cell block were prepared. The ThinPrep showed cohesive tissue particles of varying cellular density with some degree of crowding and nuclear overlap. These particles contained sheets of bland spindle cells with variably rounded to tapered nuclear ends (Figure 2). The cytoplasm of these cells was fibrillar and syncytial-appearing, making delineation of exact cell sizes/ cell borders challenging. No mitotic activity or necrosis was present. Similar-appearing cellular fragments were present on cell block sections; the fragments contained relatively uniform spindled nuclei within an eosinophilic fibrillar-appearing background. The neoplastic cells were diffusely positive for S-100 (Figure 3), and were negative for CD117, DOG1, desmin, and AE1/AE3, confirming a diagnosis of schwannoma. Because of the benign nature of the lesion, surveillance with imaging studies was undertaken in lieu of resection. Follow-up imaging 11 months after initial diagnosis revealed an increase in size of the lesion by 1 cm. A repeat fine needle aspiration (FNA) yielded a similar appearing spindle cell neoplasm, consistent with schwannoma. Schwannomas are benign nerve sheath tumors commonly arising in the head and neck and extremities, and occasionally occurring in deep-seated locations including the posterior mediastinum and retroperitoneum. Their origin in the pancreas is rare, with fewer than 70 cases reported in the literature. In a recent review, Ma and colleagues summarized the features of 68 published cases of pancreatic schwannoma. Half of patients presented with abdominal pain, but 34% were asymptomatic. The lesions were most commonly located in either the head or the body of the pancreas, and the majority (65%) had a cystic component. Similar findings were reported by Moriya et al.in an earlier study. It is well known that schwannomas often show cystic degeneration, and this common feature of pancreatic schwannoma can mimic other cystic pancreatic lesions such as pseudocysts, serous or mucinous cystic neoplasms, intraductal papillary mucinous neoplasms, solid pseudopapillary neoplasms or pancreatic neuroendocrine tumors with cystic change. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is increasingly performed for preoperative evaluation of pancreatic lesions, including pancreatic cysts. However, there are very few case reports in the cytology literature of pancreatic schwannoma diagnosed by FNA. In the cohort of cases reviewed by Ma

Barriers to the recognition of medullary thyroid carcinoma on FNA: Implications relevant to the new American Thyroid Association guidelines: Barriers to MTC Recognition on FNA

The 2016 American Thyroid Association guidelines recommend multiple endocrine neoplasia testing and evaluation for pheochromocytoma before thyroidectomy after a thyroid fine‐needle aspiration biopsy (FNA) is positive for medullary thyroid carcinoma (MTC). In the current study, the authors examined the reasons why FNA was unable to definitively diagnose MTC preoperatively, with attention to morphologic patterns that can be misleading.