10 May 2022: Image Quiz #82

Authors: Simon F. Roy, M.D.Jennifer M. McNiff, M.D.

What is the histopathological epidermal reaction pattern seen in the image below?

Select an answer:

A. Acantholysis

B. Dyskeratotic acantholysis

C. Epidermal necrosis

D. Epidermolytic hyperkeratosis

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16 June 2021: Pathology Images of the Week

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

Laboratory Administration & Management of Pathology Practices > Lean workflow / Six Sigma

An organized workspace with a space for all needed tools or materials for jobs done at the station readily allows one to identify when something is missing or out of place.

Contributed by Stephen J. Hardy, M.B.A.

Liver & intrahepatic bile ducts > Ductular reaction

The ductular profiles with complete and incomplete lumina at the portal – parenchymal interface are highlighted by CK19.

Contributed by Shahbaz Khan, M.D.

Skin nonmelanocytic tumor > Juvenile xanthogranuloma

Right leg, excision, juvenile xanthogranuloma, scattered Touton giant cells.

Contributed by Lamiaa Hamie, M.D., M.Sc. and Ossama Abbas, M.D.

Bladder, ureter & renal pelvis > Noninvasive papillary urothelial carcinoma high grade

High power showing architectural disorder, loss of polarity and nuclear pleomorphism in high grade papillary carcinoma.

Contributed by Michelle R. Downes, M.D.

Informatics, digital & computational pathology > Fluorescent microscopy applications

Interphase FISH showing translocation involving the EWSR1 gene at 22q12.

Contributed by Ruhani Sardana, M.B.B.S. and Anil Parwani, M.D., Ph.D., M.B.A.

9 June 2021: Pathology Images of the Week

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

Salivary glands > Mucoepidermoid carcinoma

Solid areas of the tumor are formed by different proportions of epidermoid (squamous) cells (red arrow), mucus cells (green arrow) and intermediate cells (yellow arrow) (histopathology, H&E stain, 10x).

Contributed by Rema A. Rao, M.D. and Saeed Asiry, M.D.

Skin melanocytic tumor > Invasive melanoma

44 year old woman with 0.8 cm nodule on her back. Scanning magnification shows a nodular melanocytic proliferation with minimal junctional component (2x).

Contributed by Michele Donati, M.D.

Skin nonmelanocytic tumor > Keratoacanthoma

An endophytic squamous proliferation with central crater filled with keratin.

Contributed by Poonam Sharma, M.B.B.S.

Bladder, ureter & renal pelvis > Urothelial carcinoma – invasive > Nested

Anastomosing, irregular, large nested and inverted growth of cytologically bland urothelium with desmoplastic stromal reaction (4x).

Contributed by Megan L. Brown, M.D. and Maria Tretiakova, M.D., Ph.D.

Esophagus > Ectopic sebaceous glands

Mature sebaceous gland within the lamina propria.

Contributed by Yukihiro Nakanishi M.D., Ph.D.

2 June 2021: Pathology Images of the Week

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

Lung > Lepidic adenocarcinoma

Noninvasive lepidic adenocarcinoma (left) juxtaposed with adjacent uninvolved lung parenchyma (right). The lepidic adenocarcinoma is characterized by thickened alveolar septa lined by atypical overlapping cuboidal cells.

Contributed by Jonathan Keow, M.D., Ph.D.

Skin nonmelanocytic tumor > Trichilemmal (pilar) type cysts

High power view of epithelial lining with maturation of squamous epithelium, which lacks a granular layer (trichilemmal differentiation).

Contributed by Aaron Muhlbauer, M.D. and Jodi Speiser, M.D.

Skin nontumor > Granuloma annulare

Palisaded granuloma annulare. Arm of a 50 year old woman.

Contributed by Stephen Somach, M.D.

Vulva, vagina & female urethra > Smooth muscle tumors

Leiomyosarcoma of the vulva, morphologically low grade, with moderately atypical, round to cigar shaped nuclei with focally prominent nucleoli (400x). Mitoses are rare (1 – 2 per 10 high power fields) and necrosis is absent.

Contributed by David B. Chapel, M.D.

Penis & scrotum > Cutaneous verruciform xanthoma

A low power view shows papillary / verrucous epithelial hyperplasia with band-like plasma cell infiltrate in the scrotum.

Contributed by Liwei Jia, M.D., Ph.D.

Autopsy & forensics > Blunt force injuries

Anterior cranial base fractures (yellow arrows).

Contributed by Lorenzo Gitto, M.D., Robert Stoppacher, M.D., Serenella Serinelli M.D., Ponni Arunkumar, M.D. and Luigi Bonaccorso, M.D.

14 April 2021: Images of the Week

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

Skin nonmelanocytic tumor > Atypical fibroxanthoma

Cytomorphologically, lesional cells are highly bizarre and atypical, with marked pleomorphism in size and shape, abundant eosinophilic cytoplasm, occasional multinucleation and numerous mitotic figures, including atypical forms (H&E, 200x).

Contributed by Pavandeep Gill, M.D. and Phyu Aung, M.D., Ph.D.

Stomach > Fundic gland polyp

Cystically dilated glands.

Contributed by Naziheh Assarzadegan, M.D.

Appendix > Enterobius vermicularis

Higher magnification shows Enterobius eggs with 1 flattened side and 1 convex side and a double layer hyaline chitin shell.

Contributed by Eiman Adel Hasby, M.D.

Bone marrow neoplastic > Atypical chronic myeloid leukemia

Bone marrow biopsy from a patient with aCML showing markedly hypercellular bone marrow with markedly increased neutrophils and myeloid precursors and mild dysmegakarypoiesis with no increase in blasts.

Contributed by Ling Zhang, M.D.

Esophagus > Undifferentiated carcinoma

Undifferentiated carcinoma at high power. Sheets of clearly high grade cells without obvious pattern of differentiation into any given cell type.

Contributed by Rondell P. Graham, M.B.B.S.


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.

7 April 2021: Images of the Week

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

Cervix > HSIL / CIN II / CIN III

At high magnification, HSIL / CIN III lacks maturation (400x).

Contributed by Khaled J. Alkhateeb, M.B.B.S.

Ovary > Fibroma

Ovarian fibroma: the cut surface reveals a dense white mass within the ovary (left); outer surface of the fibroma is smooth and lightly vascularized (right).

Contributed by Rex Bentley, M.D.

Testis & epididymis > Adult granulosa cell

Low power view of numerous small uniform spaces (microfollicles) with hyalinized basement membrane material (Call-Exner bodies).

Contributed by Kristine M. Cornejo, M.D.

Microbiology & parasitology > Zygomycetes

Evaluation of fungal forms. H&E stained FFPE tissue showing broad pauciseptate ribbon-like hyphae in necrotic sinonasal tissue.

Contributed by Sixto M. Leal, Jr., M.D., Ph.D.

Skin nonmelanocytic tumor > Syringoma

Histologic sections showing cysts, nests and cords in a paisley or tadpole shaped pattern. No cytologic atypia or mitotic figures are seen (H&E, original magnification 100x).

Contributed by Aadil Ahmed, M.D. and Sara C. Shalin, M.D., Ph.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 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.

24 November 2020: Images of the Week

Here are just a few of this week’s new images from our free, online textbook:

Bladder cytology -nonneoplastic

Degenerated infected cell with vesicular nucleus showing spider web chromatin (bladder washing, ThinPrep, 60x).

Written by Gong Feng, M.D., Ph.D.Bonnie Choy, M.D.

Metanephric adenofibroma

H&E image showing the epithelial component (bottom) and the stromal component (top).

Written by Rose Chami, M.D.

Trichoepithelioma / trichoblastoma

Cheek biopsy: trichoepithelioma with prominent keratin cyst formation. Note the bland cytologic features, cellular stroma and lack of epithelial stromal clefting (H&E, 100x magnification).

Written by Eleanor Russell-Goldman, M.D., Ph.D.

PAX8

Strong, diffuse nuclear expression of PAX8 in metastatic renal cell carcinoma involving the lung on needle core biopsy.

Written by Kelsey E. McHugh, M.D.

Thyroid gland cytology → Bethesda system, malignant

Papillary thyroid carcinoma, thyroid FNA: intranuclear cytoplasmic inclusion (arrow) and powdery chromatin (Papanicolaou, 40x).

Written by Ayana Suzuki, C.T.Andrey Bychkov, M.D., Ph.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.


17 November 2020: Image Quiz #43

Authors: V. Claire Vaughan, M.D.Joshua Wisell, M.D.

An elderly man presents to the dermatology clinic with a flesh colored papule over the lateral cheek without arborizing vessels or crust. Biopsy is shown. What is the most likely diagnosis?

Select an answer:

A. Basal cell carcinoma

B. Basaloid follicular hamartoma

C. Syringoma

D. Trichoblastoma

E. Spiradenoma

To sign up for our biweekly image quiz newsletters and more, visit pathologyoutlines.com/subscribe.html.