Case of the Month: May 2024

Clinical history

A 60-year-old woman presented with back pain since last year, weight loss in the past months, and hematuria in the past weeks. Computed tomography scan of the chest, abdomen, and pelvis showed a left renal mass measuring 11 cm in maximum dimension as well as pulmonary nodules. The patient underwent a left radical nephrectomy.

Questions:

  • What is your top differential diagnosis?
  • What areas of the tumour (name up to 3) and what parts of the radical nephrectomy specimen (name up to 3) is it important to sample at the gross bench for appropriate pathologic diagnosis, grading, and staging?
  • What adverse pathologic features does this case have?

How to participate

Take a look at the images.

Anyone is welcome to try to solve the puzzle by commenting on the related post on our Instagram.

If you are a medical student at the University of Toronto, you can also:

If you do, you are in for a chance to win a $100 gift card! (UofT Med students only).

Discover the answer to May's Case of the Month challenge!

The answer to May’s Case of the Month is clear cell renal cell carcinoma!

Clear cell renal cell carcinoma is the most common renal epithelial tumour and is characterized by its clear cytoplasm, compact nested/acinar architectural pattern, and network of arborizing small, thin walled vessels. Immunohistochemistry typically is not required for diagnosis. Most renal carcinomas are graded based on the size of the nucleoli and presence of extreme nuclear pleomorphism, tumour giant cells, and/or any amount of sarcomatoid or rhabdoid differentiation. Rhabdoid morphology was observed in this case. Important areas to section on gross examination include the margins (ureter, renal vein, renal artery) and the tumour in relation to important staging structures (renal sinus fat, perinephric fat, renal vein, collecting system, and adrenal gland).

If you are a current medical student at U of T, you can register to join the May case of the month lecture online or in person and have a chance to win a $100 gift card!

You can also join the Special Interest Group in Laboratory Medicine to learn more about Laboratory Medicine.