Conexiant
Login
  • The Analytical Scientist
  • The Cannabis Scientist
  • The Medicine Maker
  • The Ophthalmologist
  • The Pathologist
  • The Traditional Scientist
The Pathologist
  • Explore Pathology

    Explore

    • Latest
    • Insights
    • Case Studies
    • Opinion & Personal Narratives
    • Research & Innovations
    • Product Profiles

    Featured Topics

    • Molecular Pathology
    • Infectious Disease
    • Digital Pathology

    Issues

    • Latest Issue
    • Archive
  • Subspecialties
    • Oncology
    • Histology
    • Cytology
    • Hematology
    • Endocrinology
    • Neurology
    • Microbiology & Immunology
    • Forensics
    • Pathologists' Assistants
  • Training & Education

    Career Development

    • Professional Development
    • Career Pathways
    • Workforce Trends

    Educational Resources

    • Guidelines & Recommendations
    • App Notes

    Events

    • Webinars
    • Live Events
  • Events
    • Live Events
    • Webinars
  • Profiles & Community

    People & Profiles

    • Power List
    • Voices in the Community
    • Authors & Contributors
  • Multimedia
    • Video
    • Podcasts
Subscribe
Subscribe

False

The Pathologist / Issues / 2020 / Aug / Case of the Month (6)
Histology Histology Training and education

Case of the Month

08/11/2020 Quick Read (pre 2022) 1 min read

Share

A five-year-old male with history of autosomal recessive polycystic kidney disease status post-renal transplant presented to his nephrologist with increasing creatinine. Donor serologies were CMV negative, EBV positive; recipient was CMV negative, EBV negative. Due to worsening renal function, a renal biopsy was performed. Representative histologic findings are shown in the images below, including a confirmatory immunohistochemical stain performed with the antibody to simian virus 40 (SV40).

Which of the following is the most likely cause of disease?

a. Epstein Barr virus (EBV)
b. Polyoma BK virus (BKV)
c. Cytomegalovirus (CMV)
d. Herpes simplex virus (HSV)
e. Polyoma JC virus (JCV)

Click here to register your guess.

We will reveal the answer next month.

Do you have an interesting case that you would like us to feature? Email it to edit@thepathologist.com.

The Case of the Month series is curated by Anamarija M. Perry, University of Michigan.

Answer to August’s Case of the Month.

B. It often lacks high-grade histologic features, but is still considered grade IV.

The entity called “diffuse midline glioma, H3K27M mutant” was added to the World Health Organization (WHO) Classification of Tumours of the Central Nervous System in 2016 and constitutes most of the diffuse gliomas in the brainstem. They are considered WHO grade IV despite the lack of high-grade histological features and have a dismal prognosis. Most common in children, they typically occur in the pons (comprising most tumors previously called “diffuse pontine infiltrating gliomas”) and thalamus, but can be seen anywhere in the midline.

The clinical features vary by tumor location, but commonly include headache, ataxia, and sensory disturbance. MRI typically shows T2 hyperintensity and a heterogeneously enhancing infiltrative mass with T1 hypointensity. Microscopic examination reveals a variably cellular neoplasm with elongated irregular nuclei infiltrating the underlying brain parenchyma. Histologically, the differential diagnosis includes other infiltrating astrocytomas (IDH wildtype or mutant), as well as different low-grade glial neoplasms such as pilocytic astrocytoma. Like this case, many tumors show high-grade morphology (nuclear pleomorphism, mitotic activity, necrosis, and/or microvascular proliferation), but others may appear low-grade by histology. The tumor cells are usually positive for glial markers (GFAP, Olig2) and negative for neuronal markers (synaptophysin, NeuN), supporting their glial origin.

The diagnosis requires the tumor to be a diffusely infiltrating midline glioma with the H3K27M mutation (1). The most frequently used and readily available diagnostic test is immunohistochemistry with an antibody that detects the mutation in the histone 3 gene from a lysine (K) to a methionine (M) at position 27, although molecular testing can also be used. The mutant protein is located in the tumor nuclei. It is crucial to use the mutation-specific antibody and not the trimethylation-specific antibody in this same position (H3K27Me3, normally expressed in most cells), because the trimethylated label will be lost in the nuclei of tumors with the H3K27M mutation. Both can be used in combination. Importantly, the H3K27M mutation can be detected in other primary brain neoplasms including glial, glioneuronal, and ependymal tumors. In those examples, however, the mutation does not carry the dismal prognosis assigned to this entity, so caution is warranted when making this diagnosis (2,3). In pediatric patients (but potentially not in adult patients), this mutation is associated with a poorer prognosis (4).

Submitted by Rawia Mubarak Mohamed and Najla Saleh Ben Gashir, Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates. Discussion by Maria Martinez-Lage, Massachusetts General Hospital, Boston, Massachusetts, USA.

Newsletters

Receive the latest pathology news, personalities, education, and career development – weekly to your inbox.

Newsletter Signup Image

References

  1. DN Louis et al., Acta Neuropathol, 135, 639 (2018). PMID: 29497819.
  2. C Orillac et al., Acta Neuropathol Commun, 4, 84 (2016). PMID: 27519587.
  3. K Yao et al., Hum Pathol, 84, 262 (2019). PMID: 30389438.
  4. A Ebrahimi et al., J Cancer Res Clin Oncol, 145, 839 (2019). PMID: 30610375.

Explore More in Pathology

Dive deeper into the world of pathology. Explore the latest articles, case studies, expert insights, and groundbreaking research.

False

Advertisement

Recommended

False

Related Content

Your Newest Colleague?
Histology
Your Newest Colleague?

January 6, 2022

1 min read

The need for AI-based end-to-end biomarkers in oncology

Biospecimen Access For Biotechs
Histology
Biospecimen Access For Biotechs

February 14, 2022

1 min read

Quality, provenance, and “taking pot luck”

Case of the Month
Histology
Case of the Month

February 21, 2022

1 min read

The Art of the Laboratory
Histology
The Art of the Laboratory

March 25, 2022

1 min read

For the seventh time, we asked you to share the images you think capture the most beautiful, educational, or amusing aspects of pathology – and you delivered. Welcome to our gallery tour of the most visually striking discipline in medicine!

False

The Pathologist
Subscribe

About

  • About Us
  • Work at Conexiant Europe
  • Terms and Conditions
  • Privacy Policy
  • Advertise With Us
  • Contact Us

Copyright © 2025 Texere Publishing Limited (trading as Conexiant), with registered number 08113419 whose registered office is at Booths No. 1, Booths Park, Chelford Road, Knutsford, England, WA16 8GS.