Intratemporal facial nerve neurofibroma causing facial paralysis in an infant: Case report and review of the literature.

This article describes the first recorded case of intratemporal neurofibroma in an infant. A literature review of all other existing cases of intratemporal neurofibroma is performed, finding that the majority of cases involve multiple segments and can be found in the mastoid segment most often. Most common symptoms described included facial paralysis, otalgia, and conductive hearing loss, respectively.

Apprenticeship and the art of making meaning in cytopathology.

The exemplary work of Wakely et al goes beyond the diagnosis of a rare entity. Therein resides an apprenticeship in the art of cytopathology itself: making meaning from specimens.

Secretory carcinoma of the salivary gland, a rare entity: An international multi-institutional study.

BACKGROUND: Secretory carcinoma (SC) of the salivary gland is a rare entity with limited published literature on cytomorphology. The authors present the largest cohort to date of SC fine-needle aspiration (FNA) cases. METHODS: FNA cases of histologically confirmed SC were retrospectively retrieved from 12 academic institutions in the United States, Italy, Finland, and Brazil. The collated data included patient demographics, imaging findings, cytopathologic diagnoses according to the Milan System for Reporting Salivary Gland Cytopathology, cytomorphologic characteristics, and immunohistochemical/molecular profiles. RESULTS: In total, 40 SCs were identified (male-to-female ratio, 14:26) in patients with a mean age of 52 years (age range, 13-80 years). Ultrasound imagining revealed a hypoechoic, ovoid, poorly defined, or lobulated mass. The most common primary site was the parotid gland (30 of 40 tumors). Regional lymph node metastasis (9 patients) and distant metastasis (4 patients; brain, liver, lungs, and mediastinum) were noted. Two patients died of disease. FNA smears were cellular and demonstrated mainly large, round cells with intracytoplasmic vacuoles or granules and round-to-oval nuclei with smooth nuclear contour, minimal irregularities, and prominent nucleoli arranged predominantly in clusters, papillary formations, and single cells. The background was variable and contained inflammatory cells, mucin, or proteinaceous material. The diagnoses were malignant (19 of 38 tumors; 50%), suspicious for malignancy (10 of 38 tumors; 26%), salivary gland neoplasm of uncertain malignant potential (7 of 38 tumors; 18%), and atypia of undetermined significance (2 of 38 tumors; 6%) according to the Milan System for Reporting Salivary Gland Cytopathology. Two malignant cases (2 of 40 tumors; 5%) were metastases. The neoplastic cells were immunoreactive for S100 (23 of 24 tumors), mammaglobin (18 of 18 tumors), GATA-3 (13 of 13 tumors), AE1/AE3 (7 of 7 tumors), and vimentin (6 of 6 tumors). ETV6-NTRK3 fusion was detected in 32 of 33 tumors by fluorescence in situ hybridization (n = 32) and next-generation sequencing (n = 1). CONCLUSIONS: Familiarity with cytomorphologic features and the immunohistochemical/molecular profile of SC can enhance diagnostic accuracy.

Usefulness of Cyclin D1/Podoplanin Dual Immunohistochemical Stain to Differentiate Malignant Mesothelioma From Reactive Mesothelial Proliferations.

OBJECTIVES: To examine the potential of cyclin D1/podoplanin dual immunohistochemical stain to differentiate malignant mesothelioma from reactive mesothelial proliferations. METHODS: Cyclin D1/podoplanin dual immunohistochemistry was performed on 34 surgical cases of reactive mesothelial proliferations, malignant mesothelioma, and nonmesothelioma malignancies. RESULTS: All 15 reactive mesothelial proliferations demonstrated less than 50% cyclin D1 staining with variable to diffuse podoplanin staining. In 6 (60%) of 10 cases of epithelioid malignant mesothelioma, the dual stain supported the diagnosis. Less than 50% cyclin D1 staining was noted in the remaining four cases, including small biopsy specimens or cases with focal papillary architecture. The five cases of sarcomatoid/desmoplastic/biphasic mesothelioma showed more than 50% cyclin D1 staining with focal to absent podoplanin staining. Well-differentiated papillary mesothelioma appears to demonstrate less than 25% cyclin D1 staining. CONCLUSIONS: The cyclin D1/podoplanin dual stain is reliable and may be used to aid in differentiation of benign mesothelial proliferations from malignant tumors. In addition, histologic features and other ancillary testing may support the classification of cases with an inconclusive cyclin D1/podoplanin staining.

Application of the Milan System for Reporting Salivary Gland Cytopathology in pediatric patients: An international, multi-institutional study.

BACKGROUND: Pediatric salivary gland fine-needle aspiration (FNA) is uncommon with a higher frequency of inflammatory lesions and a small proportion of malignancies. This international, multi-institutional cohort evaluated the application of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) and the risk of malignancy (ROM) for each diagnostic category. METHODS: Pediatric (0- to 21-year-old) salivary gland FNA specimens from 22 international institutions of 7 countries, including the United States, England, Italy, Greece, Finland, Brazil, and France, were retrospectively assigned to an MSRSGC diagnostic category as follows: nondiagnostic, nonneoplastic, atypia of undetermined significance (AUS), benign neoplasm, salivary gland neoplasm of uncertain malignant potential (SUMP), suspicious for malignancy (SM), or malignant. Cytology-histology correlation was performed where available, and the ROM was calculated for each MSRSGC diagnostic category. RESULTS: The cohort of 477 aspirates was reclassified according to the MSRSGC as follows: nondiagnostic, 10.3%; nonneoplastic, 34.6%; AUS, 5.2%; benign neoplasm, 27.5%; SUMP, 7.5%; SM, 2.5%; and malignant, 12.4%. Histopathologic follow-up was available for 237 cases (49.7%). The ROMs were as follows: nondiagnostic, 5.9%; nonneoplastic, 9.1%; AUS, 35.7%; benign neoplasm, 3.3%; SUMP, 31.8%; SM, 100%; and malignant, 100%. Mucoepidermoid carcinoma was the most common malignancy (18 of 237; 7.6%), and it was followed by acinic cell carcinoma (16 of 237; 6.8%). Pleomorphic adenoma was the most common benign neoplasm (95 of 237; 40.1%). CONCLUSIONS: The MSRSGC can be reliably applied to pediatric salivary gland FNA. The ROM of each MSRSGC category in pediatric salivary gland FNA is relatively similar to the ROM of each category in adult salivary gland FNA, although the reported rates for the different MSRSGC categories are variable across institutions.

Epithelioid Sarcoma of the Tongue: An Unusual Tumor Mimic for Squamous Cell Carcinoma.

INTRODUCTION: Epithelioid sarcoma is a rare soft tissue malignancy that usually presents in the distal extremities along fascial planes, aponeuroses or tendon sheaths. Very rarely, it presents as a primary or metastatic lesion of the head neck. METHODS: Chart review and comprehensive literature review using PubMed and Google Scholar. RESULTS: A 17-year-old non-smoker was referred for evaluation of an ulcerative lesion of the right anterior-lateral tongue, progressing over several months. Incisional biopsy was concerning for squamous cell carcinoma. He underwent partial glossectomy and bilateral selective neck dissections, with reconstruction using a radial forearm free flap. Final pathology was consistent with epithelioid sarcoma, proximal type, demonstrating perineural invasion and close margins. Post-operative PET scan showed no persistent nor metastatic disease. He underwent post-operative radiation therapy to a total dose of 56 Gy to the primary site. CONCLUSION: Epithelioid sarcoma is a rare malignancy usually presenting in the extremities of young adults, which uncommonly presents in the head and neck as a primary or metastatic lesion. The infrequency of these lesions has prevented development of evidence-based treatment recommendations. As with most sarcomas, surgery is the mainstay of therapy for epithelioid sarcoma, while radiation has been used in an adjunctive role. Although a rare lesion, epithelioid sarcoma should be considered in the differential diagnosis for atypical epithelioid lesions of the tongue and oral cavity when patient demographics, gross lesion characteristics, or histopathology are not entirely consistent with more common lesions, such as squamous cell carcinoma.

Assessing the diagnostic accuracy for pleomorphic adenoma and Warthin tumor by employing the Milan System for Reporting Salivary Gland Cytopathology: An international, multi-institutional study.

BACKGROUND: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has established distinct diagnostic categories for reporting cytopathological findings, and each is associated with a defined risk of malignancy (ROM). However, the ROM is applied at the overall category level and is not specific for particular morphological entities within a category. Here, the diagnostic performance of the MSRSGC for pleomorphic adenoma (PA) and Warthin tumor (WT) is reported. METHODS: The pathology archives of 11 institutions from 4 countries were retrospectively searched to identify all salivary gland fine-needle aspiration (FNA) biopsies with a differential or definitive diagnosis of PA or WT and all resection specimens with a diagnosis of PA or WT; only paired cases were included. All FNA diagnoses were retrospectively classified according to the MSRSGC. RESULTS: A total of 1250 cases met the inclusion criteria, and they included 898 PA cases and 352 WT cases. The ROM in the benign neoplasm category was 3.0% and 1.3% for cases with a differential or definitive diagnosis of PA and WT, respectively. The ROM in the salivary gland neoplasm with uncertain malignant potential (SUMP) category was 2.7% and 18.8% for PA and WT, respectively (P = .0277). The diagnostic accuracy for PA and WT was 95.1% and 96.1%, respectively. CONCLUSIONS: The diagnostic accuracy for PA and WT on FNA is high. Furthermore, these findings highlight the difference in the ROMs associated with 2 specific differential diagnoses in the SUMP category: basaloid neoplasms and oncocytoid neoplasms.

Lung cancer and molecular testing in small biopsies versus cytology: The Logics of Worlds.

The 8th Annual National Molecular Cytopathology Meeting, held in Naples, Italy, on December 2 to 3, 2019, addressed updates in diagnostic cytopathology and molecular classifications and specifically focused on lung cancer biomarker testing in cytology samples. Lung cancer continues to be the most commonly diagnosed noncutaneous malignancy in the world. In the majority of patients, lung cancers are frequently identified when they cannot be surgically accessed, and this leads to the use of cytology for a diagnosis and theragnostic testing. The meeting was an international forum for discussing new roles and updates for cytopathology in molecular testing as the basis for provoking new trends and novel approaches. The relevant literature is referenced. The significance of these updates for the practice of pathology in general is discussed.