Most common cause of a Krukenberg tumour is
**Core Concept**
Krukenberg tumors refer to metastatic gastric cancer to the ovaries, typically presenting as bilateral ovarian masses with mucin-filled signet ring cells. This phenomenon is a manifestation of the metastatic spread of a primary abdominal malignancy.
**Why the Correct Answer is Right**
The most common primary tumor associated with Krukenberg tumors is gastric adenocarcinoma, particularly the intestinal type. This type of cancer tends to spread to the ovaries via the bloodstream, where it forms mucin-filled signet ring cells. The presence of these cells is a hallmark of Krukenberg tumors. The gastric cancer cells are thought to implant in the ovarian stroma, where they proliferate and form a secondary tumor.
**Why Each Wrong Option is Incorrect**
**Option A:** While breast cancer can metastasize to the ovaries, it is not the most common cause of Krukenberg tumors.
**Option B:** Ovarian cancers, such as serous carcinomas, can also metastasize to the ovaries, but they are not typically associated with Krukenberg tumors.
**Option C:** Other primary malignancies, like colorectal cancer, can metastasize to the ovaries, but they are less commonly associated with Krukenberg tumors.
**Clinical Pearl / High-Yield Fact**
Krukenberg tumors are often bilateral and can mimic the appearance of ovarian cystadenocarcinomas, making them challenging to diagnose. A biopsy of the ovarian mass can confirm the presence of signet ring cells and establish the diagnosis.
**Correct Answer: D. Gastric adenocarcinoma.**