8 November 2022: Case of the Month #521

Thanks to Drs. Leandro Freitas, Ana Grizotto and Athanase Billis, State University of Campinas (Unicamp), Campinas, Brazil and the Genitourinary Pathology Society (GUPS), for contributing this case and discussion and to Dr. Debra Zynger, Ohio State University, Columbus, Ohio, USA for reviewing the discussion.

Clinical history:

A 76 year old man with an incidental renal tumor in the lower pole of the right side of a horseshoe kidney underwent a partial nephrectomy.

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1 November 2022: Image Quiz #94

Author: Shreeram Akilesh, M.D., Ph.D.

A patient with COVID-19 presents with nephrotic range proteinuria and the finding on the kidney biopsy is shown below. Mutations in which gene are linked with a higher risk of developing this pathologic lesion in the kidney?

Select an answer:

A. APOL1

B. CD2AP

C. FANCD2

D. LRP2

E. NPHS1

See the answer

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28 July 2021: Pathology Images of the Week

Here is a selection of new images from our free, online textbook:

Breast > Fibromatosis

Spindle cells appear bland with no mitotic activity.

Contributed by Carissa LaBoy, M.D.

CNS tumor > Diffuse leptomeningeal glioneuronal tumor

Tumor cells with a low grade, monomorphic appearance showing perinuclear haloes, reminiscent of oligodendroglioma (200x overall magnification).

Contributed by Katherine Schwetye, M.D., Ph.D.

Kidney nontumor > Congenital nephrotic syndrome

Prominent cystically dilated proximal and distal tubules with an attenuated epithelium (periodic acid-Schiff stain).

Contributed by Chunlai Zuo, M.D., M.S. and Jonathan E. Zuckerman, M.D., Ph.D.

Ovary > Serous cystadenoma / adenofibroma

Large serous cystadenoma with localized (less than 10% of sampled cyst wall) epithelial proliferation. No complex papillary growth is seen (H&E, 100x).

Contributed by Catherine J. Roe, M.D. and Krisztina Hanley, M.D.

Stains & CD markers > Special AT-rich sequence-binding protein 2 (SATB2)

Colon neuroendocrine tumor, well differentiated (SATB2).

Contributed by Sepideh Besharati, M.D.

28 April 2021: Pathology Images of the Week

Here is a selection of new images from our free, online textbook:

Ovary > Mucinous borderline tumor / atypical proliferative mucinous tumor

Multiloculated cyst with mucinous contents and smooth external surface.

Contributed by Russell Vang, M.D.

Placenta > Decidual arteriopathy

Advanced decidual arteriopathy with fibrinoid necrosis. Arteries are distended and show endothelial injury (detachment from the wall, arrow) and fibrinoid necrosis of the media (*). 200x original magnification.

Contributed by Jonathan L. Hecht, M.D., Ph.D.

Breast > Tubular adenoma

Eosinophilic secretions present in the lumens of some of the tubules (H&E, 20x magnification).

Contributed by Joshua J.X. Li, M.B.Ch.B. and Gary M. Tse, M.B.B.S.

Breast > Metaplastic carcinoma

Moderate to markedly cytologic atypia and frequent mitosis (200x).

Contributed by Huina Zhang, M.D., Ph.D.

Placenta > Maternal vascular malperfusion

Infarction (fresh): infarcts are typically pyramidal shape and involve the maternal floor of the placenta. Older infarcts are white, while more recent infarcts are red / heterogeneous in the fresh state.

Contributed by Jonathan L. Hecht, M.D., Ph.D.

Salivary glands > Acinic cell carcinoma

Parotid gland FNA of acinic cell carcinoma. The neoplastic cells are large with abundant finely vacuolated to granular cytoplasm (Diff-Quik).

Contributed by Arash H. Lahouti, M.D.

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For desktop / tablet, you can either use the Google search bar in the upper right corner or visit PathologyOutlines.com and then scroll down to where the 59 chapters are listed, as demonstrated below.

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21 April 2021: Pathology Images of the Week

Here is a selection of new images from our free, online textbook:

Kidney nontumor > Acute pyelonephritis

Acute inflammation / pus in renal calyx.

Contributed by Jian-Hua Qiao, M.D.

Liver & intrahepatic bile ducts > Combined hepatocellular carcinoma-cholangiocarcinoma

Unequivocal cholangiocytic (red arrow) and hepatocytic (blue arrow) areas of cell differentiation. The hepatocytic area shows tumor cells organized in trabeculae (H&E 100x).

Contributed by Aurélie Beaufrère, M.D.

Bone marrow neoplastic > Myeloid neoplasms with germline predisposition and other organ dysfunction with GATA2 mutation

Bone marrow core biopsy of the same patient shows megakaryocytic dysplasia (small, hypolobated) (H&E, 40x).

Contributed by Wei Wang, M.D., Ph.D.

CNS tumor > Pituicytoma

Nuclear expression of TTF1 is ubiquitous.

Contributed by Federico Roncaroli, M.D.

Muscle & peripheral nerve nontumor > Immune mediated necrotizing myopathy

Thigh muscle from a 49 year old woman with progressive proximal weakness and creatine kinase in the 7,000s. Histology shows a pauci-inflammatory IMNM. The necrotic fibers are randomly distributed and temporally heterogeneous. There is also moderate fiber size variation and frequent internalized nuclei, suggesting that myofiber damage has been going on for a while (H&E, 20x).

Contributed by Chunyu “Hunter” Cai, M.D., Ph.D.

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How can you search the textbook?

For desktop / tablet, you can either use the Google search bar in the upper right corner or visit PathologyOutlines.com and then scroll down to where the 59 chapters are listed, as demonstrated below.

For mobile, visit PathologyOutlines.com, click on “Chapters by Subspecialty” (as demonstrated below) and then click on the subspecialty, chapter and topic.

For any device you can use your favorite browser and type in PathologyOutlines.com in addition to the search term.

16 February 2021: Images of the Week

Here is a selection of new images from our free, online textbook:

Bone marrow neoplastic > AML with t(8;21)(q22;q22)

Scattered blasts with prominent eosinophilic granules and rare Auer rods (leftmost blast).

Contributed by Sean Gu, M.D., Ph.D. and Alexa J. Siddon, M.D.

Kidney tumor > Adult renal cell carcinoma – common > Chromophobe eosinophilic variant

Chromophobe renal cell carcinoma eosinophilic variant, demonstrating diffuse marked perinuclear clearing / halos.

Contributed by Timothy Isaac Miller, M.D., M.A. and Maria Tretiakova, M.D., Ph.D.

Liver & intrahepatic bile ducts > Glycogenic hepatopathy

Pale and enlarged hepatocytes in a mosaic pattern with prominent cytoplasmic membranes and scattered background macrovesicular steatosis (200x).

Contributed by Raul S. Gonzalez, M.D.

Ovary > Endometrioid carcinoma

Back to back endometrioid glands; no solid component is seen.

Contributed by Ozlen Saglam, M.D.

Prostate gland & seminal vesicles > Low grade PIN

Atypical acinar cells with few scattered nucleoli growing in a tufted architecture (40x).

Contributed by Nicholas P. Reder, M.D., M.P.H.

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How can you search the textbook?

For desktop / tablet, you can either use the Google search bar in the upper right corner or visit PathologyOutlines.com and then scroll down to where the 60 chapters are listed, as demonstrated below.

For mobile, visit PathologyOutlines.com, click on “Chapters by Subspecialty” (as demonstrated below) and then click on the subspecialty, chapter and topic.

For any device you can use your favorite browser and type in PathologyOutlines.com in addition to the search term.

10 February 2021: Images of the Week

Here is a selection of new images from our free, online textbook:

Breast > Sparganosis

Host reaction of rimming chronic inflammation and dense fibrosis around parasite (H&E, 4x)

Contributed by Bobbi Pritt, M.D.

CNS tumor > Pituitary adenoma

Sheet-like proliferation of monomorphous cells. Absence of acinar architecture. Frozen section, 20x.

Contributed by Michael Punsoni, M.D.

CNS tumor > Medulloblastoma, SHH activated

Nodular desmoplastic medulloblastoma, SHH activated. High power H&E shows sheets of undifferentiated cells with scattered mitotic figures and apoptotic bodies. Focal anaplastic features are present (cell wrapping, center of image).

Contributed by John DeWitt, M.D., Ph.D.

Kidney tumor > Adult cystic nephroma

Multiple thin walled cysts with smooth lining.

Contributed by Bonnie Choy, M.D.

Autopsy & forensics > Forensic entomology

The irregular, superficial surface erosion of the skin, usually orange-pink to yellow in color and the absence of hemorrhage is typical of postmortem ant feeding artifact.

Contributed by Priya Banerjee, M.D.

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How can you search the textbook?

For desktop / tablet, you can either use the Google search bar in the upper right corner or visit PathologyOutlines.com and then scroll down to where the 60 chapters are listed, as demonstrated below.

For mobile, visit PathologyOutlines.com, click on “Chapters by Subspecialty” (as demonstrated below) and then click on the subspecialty, chapter and topic.

For any device you can use your favorite browser and type in PathologyOutlines.com in addition to the search term.

16 December 2020: Micro Images of the Week

Here is a selection of new images from our free, online textbook:

Adenosis

Expanded terminal duct lobular unit and adjacent (upper left) normal size terminal duct lobular unit (H&E, 4X).

Contributed by Julie M. Jorns, M.D.

Congenital mesoblastic nephroma

Tumor composed of intersecting fascicles of spindle cells.

Contributed by Ellen D’Hooghe, M.D. and Gordan M. Vujanic, M.D., Ph.D.

Large B cell lymphomas: ALK+ LBCL

ALK positive large B cell lymphoma with ALK positivity (bone marrow, IHC, 200x).

Contributed by Marie Therese Manipadam, M.B.B.S., M.D.

Molecular aspects of pancreatic cancer

Site: pancreatic head. Procedure: Whipple resection. Diagnosis: medullary pancreatic ductal adenocarcinoma. Histologic finding: neoplastic cells with syncytial growth and without gland formation (hematoxylin eosin, original magnification 10x). Molecular findings: microsatellite instability is very common in the case of medullary histology.

Contributed by Claudio Luchini, M.D., Ph.D.

Chronic sialadenitis / sialolithiasis

40 year old man with submandibular pain; chronic inflammation with acinar atrophy and fibrosis (10x).

Contributed by James S. Lewis, M.D.

How can you search the textbook?

For desktop / tablet, you can either use the Google search bar in the upper right corner or visit PathologyOutlines.com and then scroll down to where the 61 chapters are listed, as demonstrated below.

For mobile, visit PathologyOutlines.com, click on “Chapters by Subspecialty” (as demonstrated below) and then click on the subspecialty, chapter and topic.

For any device you can use your favorite browser and type in PathologyOutlines.com in addition to the search term.

3 November 2020: Image Quiz #42

Authors: Fenghua Peng, M.D., Ph.D., Jonathan E. Zuckerman, M.D., Ph.D.

Which of the following is true about IgG4 related disease in the kidney?

Select an answer:

A. Always involves the kidney diffusely

B. Dense lymphoplasmacytic cell infiltration is common

C. Interstitial inflammation and fibrosis are usually absent

D. Most patients tend to be young women

See the answer

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