Case of the day: Mediastinal mass in a 80 year old male with history of melanoma. Mass is encapsulated, frozen section shows lymphoid proliferation, flow cytometry detects CD4/CD8 double expression cells.

1/ #breastpath lovers, have you heard about this new entity of "serous carcinoma-like" breast carcinoma? 😉 #pathology #IHCpath- the IHCs showed negativity for ER, PR, HER2, GATA3, Sox10

Case 5 Reninoma/Juxtaglomerular cell tumor. Neoplasm of renin-secreting cells. Renin+, vimentin+, CD34+, and CD117+. Electron microscopy shows rhomboid crystals of renin protogranules.

Pathologists! Check out this enlarged lymph node with a florid proliferation of monocytoid B cells, suspicious for lymphoma, but with no immuno phenotypic evidence of clonality. Turned out to be CMV lymphadenitis with many classic viral inclusions.#Hemepath #CMV

More images …just get an idea the lesional cells are uniform, but not very “naive”… DDx?

Malignant melanotic nerve sheath tumor (MMNST): heavily pigmented, pleomorphic, SOX10/Melan-A positive (shown), often paraspinal in younger patients. Key to distinguish from melanoma—MMNST frequently has PRKAR1A inactivation. #BSTpath #Dermpath

55 year-old female, palpable breast mass, ER-, PR-, HER2-, P63- and SMM-.

Lymphoplasmacytic lymphoma with diffuse homogeneous expression of CD10; could be mistaken for low grade follicular lymphoma at initial work-up #Hemepath #Lymsm #MedEd #Surgpath #MedX #MedTwitter #SoMe #Bmtsm

F, 40s, breast nodule. Dr. Luca Olaleke Folaranmi Fouad Boulos Raza Hoda MD Alexander Damron, MD Brian McMillen MD Liza Quintana, MD Tania Labiano Aurélien Morini, MD, MSc 🇫🇷🇪🇺💙💛 Celina Stayerman MD Nusrat Z. Bokhari Amal Asar, FRCPath, MAcadMED Tristan Rutland MBBS FRCPA IFCAP Israh Akhtar Khan Lorand Kis Padma Priya J Barry McGinn Pascual Meseguer Med Amine, MD 🔬 Kalyani Bambal #breastpath

Soft tissue, abdominal wall, debridement: Hx: Non healing wound. This is what you see. How would you sign it out? What stains would you order? #PathX #pathquiz Michigan Pathology

Tuesday #dermpath and #BSTpath special. 😆🔬 Extramedullary hematopoiesis is a rare occurrence in solid malignancies, including solitary fibrous tumor (SFT). Here’s an interesting example of this fascinating phenomenon in action. #MDACCPath #pathology

Spot on! This Alk negative anaplastic large cell lymphoma had a DUSP22 rearrangement. Clues are the positive LEF1 and absence of cytotoxic granules. #lymphoma #anaplasticlargecelllymphoma #hemepath

Core needle biopsy of a retro areolar mass in a male. Let me know what stains you want! #pathology #breastpath #pathX #pathtwitter #pathresidents

71 y.o. F. What is your diagnosis? More photos in chat. #PathTwitter Mass General Brigham Pathology MGH Pathology

Mass General Brigham Pathology MGH Pathology

65 yo male with an oropharyngeal mass.

24 yo woman, no relevant medical history, - Left upper quadrant pain. - 15 cm splenic mass identified on CT scan. - Splenectomy. Dx? #hemepath

Let’s review spindled lesions of breast this week! Case of Fascicular Pseudoangiomatous Stromal Hyperplasia (PASH) 🔬 This PASH variant shows fascicular bundles of myofibroblasts & mimics other spindled tumors. Have a meaningful Memorial Day 🇺🇸 #PathX #PathTwitter #breastpath

Colonic biopsies from an adult. Diagnosis and likely clinical history? P.S.: Didn't quite read the textbook #GIpath #pathology #pathX

I can't really explain why it looks so much like Sevelamer. According to this paper by Michael Arnold, MD, PhD, BASs should be homogeneous. pubmed.ncbi.nlm.nih.gov/24921636/ However, it does say that it can show fracture lines which may resemble fishscales. 👇