Essential Questions to ask if you or a loved one has been diagnosed with Mesothelioma ***IMPORTANT***

Epithelial Mesothelioma Subtypes

Posted on: October 13, 2023 *Updated on: May 27, 2024

Subtypes of epithelial mesothelioma, which is one of the main cell types of malignant mesothelioma. Among the different cell types of mesothelioma, epithelial (or epithelioid) is the most common and generally has the best prognosis.

The various subtypes of epithelial mesothelioma have distinct morphological appearances under the microscope, and indeed, their identification can have implications for diagnosis, prognosis, and treatment. Here’s a brief overview of the subtypes you mentioned:

  1. Adenomatoid (Microglandular): Resembles miniature glands and can be seen in both pleural and peritoneal mesothelioma. As mentioned, the peritoneal form has a more benign behavior and better response to treatments.
  2. Deciduoid: A rare subtype mainly reported in the peritoneum, particularly in young women. Due to its rarity and unique appearance, it can be mistaken for other cancers.
  3. Glandular: These cells have a gland-like appearance, similar to adenocarcinomas that might have metastasized to the pleura. Distinction between primary adenocarcinomas of the lung and glandular mesothelioma can be challenging but is crucial.
  4. Small Cell: Resembles small cell carcinoma, a type of lung cancer. The survival rate for patients with this subtype is less favorable than some of the other epithelioid subtypes.
  5. Solid: This subtype can vary in its differentiation. While well-differentiated solid cells can resemble benign hyperplasia, poorly differentiated cells can look similar to other aggressive tumors.
  6. Tubulopapillary: This subtype is common and has features that can mimic adenocarcinomas in the pleura. It’s distinct from benign well-differentiated papillary mesothelioma.

Understanding these subtypes is essential for pathologists and clinicians, as the treatment approach, prognosis, and differential diagnosis considerations might vary based on the subtype. Immunohistochemical staining, which uses antibodies to detect specific proteins in cells, plays a pivotal role in distinguishing mesothelioma from other tumors and further classifying its subtype.

If someone is diagnosed with mesothelioma, it’s crucial to have the diagnosis and subtype confirmed by an experienced pathologist, ideally one who specializes in pleural or peritoneal tumors. This ensures accurate diagnosis and appropriate treatment planning.