Mohamed A H Ahmed, MD, PhD, FRCPath

@Janiranavarro Super rare!

Histopathologic Flavors of Metastatic Prostate Carcinoma - Undifferentiated 🔷 High-grade carcinoma 🔷 Typically NKX3.1/AR negative. Neuroendocrine markers can be spotty/nonspecific. NGS can be helpful in reaching the diagnosis of prostate origin. Dr. Chan #USCAP2026 #pathology #PathX #PathTwitter

@slusagar @kriyer68 @garreyf If you do include them in your biopsy report, what is the direct clinical implication? Do surgeons make sure to take more tissue around the apex in those particular cases? You do mention it then in the tumour board/ MDT?

@garreyf great question! while apical skel muscle does NOT constitute EPE as you well know, there is lit 👇🏼saying it should be reported (risk of + apical margin at RP) in our group, we do include presence/absence of this in our synoptic summary table for prostate bx

Prostate apex core needle biopsy. Does this finding require a more careful apical dissection if a radical prostatectomy is performed ? ie should we ever report? @slusagar

#GUpath nephrectomy: Dx: clear cell papillary renal cell tumor (I wish they'd named it clear cell TUBULOPAPILLARY renal tumor to emphasize morph!) here,😍example of "shark smile" (tubulopapillary morph)🔬, as some cases lack prominent "reverse-apical" nuclei!

Malignant phyllodes tumor with heterologous pleomorphic liposarcoma #breastpathology #pathology

#GUPath #Surgpath #Pathtwitter #PathX #Pathresidents: Let’s take a look at two biopsy cores (from the same patient) and decide what to call them. Take a look at both cases (“A” in this post, “B” in reply). Cast your vote. Then, read on for some teaching points geared towards trainees and general fans of #GUPath.

#GUpath #grosspath nephrectomy with central scar: DDx: oncocytoma, chromophobe RCC...but also LOT! 🔬compact nests, loose cord-like nests floating in stroma, lymphocytic aggregates 🎨pos CK7/GATA3/L1CAM, neg CD117/CK20, retained SDHB 🧪another entity in TSC/MTOR family

Frozen section of paratesticular mass. Characteristic features include dilated channels simulating vessels and prominent smooth muscle stroma and cells with cytoplasmic vacuoles. Right FS diagnosis saves the testis. #gupath #urology

A study in Virchows Archiv examines GPNMB immunohistochemistry in TFEB-altered renal cell carcinomas (RCCs). All 25 cases showed GPNMB positivity, indicating its potential as a sensitive screening marker for these tumors. bit.ly/4sja0oG

DCIS with clinging architecture vs flat epithelial atypia (FEA) Dr Sciallis Cleveland Clinic MPS #Breastpath #pathtwitter #PathX #pathology #PathResident #NIPPathX

A primer on Metanephric Adenoma mayoclinicproceedings.org/article/S0025-…

Join us for the annual William Barriss McAllister, Jr., Memorial Lecture @YaleMed on Thurs., March 5 at 12:30 PM ET as @JLHornick of @HarvardMed & @BrighamWomens, presents on, “Beyond Lineage: Diagnostic & Predictive Molecular Immunohistochemistry” shorturl.at/e5Aj9

Large Nested Urothelial Carcinoma on H&E 🔬 Deceptively bland cytology with expansile, well-circumscribed nests infiltrating the lamina propria—an architectural wolf in sheep’s clothing. Recognition is critical to avoid underdiagnosis of this aggressive variant. #Pathology

Can you make the diagnosis of TFE3 rearranged rcc on needle biopsy? Yes!: 1) if you think about it and 2) are lucky to have enough tissue! (confirmed NONO:TFE3) TFE3 IHC is not perfect but can be helpful as part of a screening panel #GUPATH #pathology #pathres #kidneycancer

@LaraHarikMD @drmehrarohit @rovingatuscap @h_alahmadie @slusagar @priyaraomd @MiPathKunju @VarshaManuchaMD @lalpritu @Williamson_SR @MichelleDunno17 Nice case! I presume the intrachromosal inversion (inv(X)(p11.2;q12) was confirmed by RNA sequencing, because TFE3-NONO will give false negative or often subtle split signal on FISH if using Break-apart probes.

#Kidney biopsy, ⚠️unusual case (v rare) 70 yo male ⚡️notice 2 morphologically distinct areas IHC and answer 👇 #rare #GUPATH #pathology #pathres

@DrChoueiri @GU_Path_Society @MichelleDunno17 @DanaFarber @DanaFarber_GU Well deserved… congratulations

Congratulations @MichelleDunno17 from all of us @DanaFarber and @DanaFarber_GU for being a role model of the best GU pathologist anyone can wish for ! Richly deserved !

ALK-rearranged RCC are rare and can have variable morphologic features. Here we describe some of these unusual tumors including an ALK-rearranged mesenchymal neoplasm: nam12.safelinks.protection.outlook.com/?url=https%3A%…

In primary aldosteronism, HISTALDO may overcall non-classical cases, missing curable resections. A simple “B2 ratio” (size of dominant vs 2nd-largest nodule) boosts accuracy and predicts surgical success. Better diagnosis = better outcomes. @EJEndo academic.oup.com/ejendo/advance…

#GUpath folks assessing🔬non-neoplastic kidney of renal tumor nephrectomy