Med Amine, MD 🔬

Mesothelial cell : tips and tricks for cytology of effusions. #cytopath #PathBoards

Neuroendocrine tumors of the breast WHO 6th edition (beta version online) 1. Primary neuroendocrine tumors (grade 1 or 2) 2. Primary neuroendocrine carcinomas: Small cell NEC is only recognized. ***Large cell neuroendocrine carcinoma is no longer recognized as a separate breast entity and should be reclasified as IBC NST with neuroendocrine differentiation*** Dr. Tan #USCAP2026 #pathology #PathX #PathTwitter #everydaybreastpath

Progestin effects in benign endometrium What you see: - Surface papillations - Dilated glands - Breakdown, necrosis, and plasma cells Dr. Castrillon #USCAP2026 #pathology #PathX #PathTwitter #everydayGYN

✅ Leydig Cell Tumor 🎯🔬 • Polygonal cells with abundant eosinophilic to lipid-rich cytoplasm and prominent nucleoli • Often produces estrogens leading to gynecomastia; Reinke crystals are pathognomonic • Malignant cases frequently harbor MDM2 and CDK4 amplifications • MDM2 amplification drives aggressive behavior and can be detected by IHC

WHO endometrioid intraepithelial neoplasia/atypical hyperplasia (EIN/AH) criteria 1. Architectural/cytologic distinctiveness AND 2. Gland crowding (glands exceed stroma) Case on the left: Meets criteria 1 and 2. Case on the right: Crowding alone. What should you do? EIN/AH diagnosis can fit in this case ***The diagnosis of EIN sometimes requires a flexible approach.*** Dr. Castrillon #USCAP2026 #pathology #PathX #PathTwitter #everydayGYN

Attenuated to absent myoepithelial cells in benign and non‐invasive breast lesions—potential diagnostic pitfalls - Laokulrath - Histopathology - Wiley Online Library onlinelibrary.wiley.com/doi/10.1111/hi…

*Microcystic Stromal Tumor (MST) of the ovary* Usually benign neoplasm with a classic triad: microcysts, solid cellular areas, and fibrous stroma. IHC: Nuclear β-catenin, cyclin D1, WT1, and SF1 positivity Key genetics: Mutually exclusive CTNNB1 or (less commonly) APC mutations → Rarely, MST is an extracolonic manifestation of familial adenomatous polyposis (FAP) and can serve as a sentinel event leading to the diagnosis of FAP Dr. Parra Herran #USCAP2026 #pathology #PathX #pathtwitter

#PathQuiz 🔬🎀 #BreastPath A) Secretory carcinoma B) Tall cell carcinoma with reversed polarity C) Solid papillary carcinoma D) Invasive micropapillary carcinoma #Pathology #BreastPath Clue in caption 🧐

Interesting case to share : What's your diagnosis ? #PathTwitter #PathX

Despite simplified diagnostic criteria, intraobserver and interobserver variability remain in the interpretation of colorectal serrated polyps onlinelibrary.wiley.com/doi/10.1111/hi… #GIpath

#PathQuiz 🔬 Clue in caption 🧐 A) Intraductal tubulopapillary neoplasm B) Biliary intraepithelial neoplasia C) Gallbladder carcinoma D) Bile duct adenoma #Pathology #GIPath @IARCWHO

Common pitfall in lung cytopathology Cytology mimicking adenocarcinoma (pic 1) If you get a core biopsy and see a dissociation between CK AE1/AE3 and TTF-1 staining, stop! Lung cells are not CK AE1/AE3 negative and TTF-1 positive; only stromal cells in sclerosing pneumocytoma are (pic 3). Clues for sclerosing pneumocytoma in cytology (very hard diagnosis to make): - Foamy macrophages, cuboidal cells, IHC (CK-, TTF-1+) - Clinical clues: young to middle-aged women Dr. Mukhopadhyay - Pathology on The Coast 2025, CAP On Demand #pathology #pathX #pathtwitter #CAP

Review the biomarkers in cervical squamous neoplasia, part of the Archives Special Section on the 11th Princeton Integrated Gynecologic Pathology Symposium, here 👉 doi.org/10.5858/arpa.2… #CAP #Archives #Pathology #GynPathology

2026 marks the release of two highly anticipated WHO classifications: Breast Tumours and Digestive System Tumours, 6th edition.

#PathQuiz 🔬 A) Fundic gland polyp B) Gastric hyperplastic polyp C) Gastric adenoma D) Pyloric gland adenoma #Pathology #GIPath

New in @Human_Pathology: ✌🏻 reviews in the 2026 Pathology Updates issue on GU pathology—bladder, prostate, kidney, testis, and penile tumors. Grateful to great co-authors—hope it’s useful for pathologists and trainees! 🔗 sciencedirect.com/science/articl… 🔗 sciencedirect.com/science/articl…

✅ Benign Ductal Cells 🎯 • Scant to moderate cellularity with cohesive two-dimensional flat sheets and honeycomb groups. • Small uniform round to oval nuclei with smooth membranes and fine chromatin; nucleoli are inconspicuous. • Myoepithelial or bipolar nuclei may be present and help support benignity; background is typically clean. • Represents normal or reactive ductal epithelium; interpret atypia in clinical and radiologic context. • 🐝 Honeycomb: Flat honeycomb sheet pattern of benign ductal cells.

#CytoQuiz 🫁 A) Squamous Cell Carcinoma B) Adenocarcinoma C) Small Cell Carcinoma D) Reactive Bronchial Cells #CytoPath #Pathology 🔬 🖼️ @CytoAtlas

Rare Presentations of Ovarian Tumors to Be Aware Of High-grade anaplastic transformation of ovarian serous borderline tumor: Most cases present as SBT with abrupt transition to a high-grade component, but one case presented as usual SBT with recurrence as high-grade component. Dismal prognosis. Dr. Parra-Herran - Special Lecture: High-impact publications from the recent GYN path literature #isgyp #pathology #PathX

Tenosynovial giant cell tumor-"Atypical" features The presence of these features (see list below) doesn't mean it is a malignant tumor -pitfall 🛑 -Vascular invasion (pic 2) -Bone involvement (pic 3) but no histologic features of malignancy -Extraarticular location (pic 4) Dr. Nielsen-Neoplastic and Non-Neoplastic Lesions of the Synovium #USCAP25 #PathX #BSTpath