**Question:** Krukenberg tumour of ovary is due to carcinoma of

A. Colorectal cancer
B. Breast cancer
C. Ovarian cancer
D. Endometrial cancer

**Correct Answer:** D. Endometrial cancer

**Core Concept:** Krukenberg tumor is a rare form of ovarian cancer that originates from the dissemination of malignant cells from another primary cancer site, typically in the gastrointestinal tract (colorectal, stomach, or pancreas).

**Why the Correct Answer is Right:** Krukenberg tumor is a result of the spread of malignant cells from a primary cancer site (endometrial cancer, colorectal cancer, breast cancer, or stomach cancer) to the ovaries. In this case, the correct answer is endometrial cancer.

**Why Each Wrong Option is Incorrect:**

A. Colorectal cancer (Option A): While colorectal cancer can spread to the ovaries, it is less likely to present as a Krukenberg tumor compared to endometrial cancer.
B. Breast cancer (Option B): While breast cancer can spread to the ovaries, it is less likely to present as a Krukenberg tumor compared to endometrial cancer.
C. Ovarian cancer (Option C): Krukenberg tumor is a specific type of ovarian cancer originating from the dissemination of malignant cells from another primary cancer site, thus making endometrial cancer the correct answer rather than an ovarian cancer.
D. Endometrial cancer (Correct Answer): Endometrial cancer is the most common primary cancer site associated with Krukenberg tumor, making it the correct answer.

**Clinical Pearl:** Krukenberg tumor is a clinical entity that highlights the importance of considering secondary malignancies when evaluating a patient with a peritoneal tumor deposit and a history of a primary malignancy. A thorough clinical history, physical examination, and imaging studies are essential for identifying the primary cancer site.

**Core Concept:** Krukenberg tumor is a type of ovarian cancer that arises from the dissemination of malignant cells from another primary cancer site, usually in the gastrointestinal tract (colon, stomach, or pancreas), or in the female genital tract (endometrial or cervical cancer).

**Why the Correct Answer is Right:** Krukenberg tumor results from the dissemination of malignant cells from another primary cancer site, and endometrial cancer is the most common primary malignancy associated with Krukenberg tumor.

**Why Each Wrong Option is Incorrect:**

A. Colorectal cancer (Option A): While colorectal cancer can lead to peritoneal dissemination, it is less likely to result in Krukenberg tumor compared to endometrial cancer.
B. Breast cancer (Option B): Breast cancer is even less likely to present as a Krukenberg tumor compared to endometrial cancer.
C. Ovarian cancer (Option C): Krukenberg tumor is a specific type of ovarian cancer that develops from the dissemination of malignant cells from another primary cancer site, not an ovarian cancer itself.
D. Endometrial cancer (Correct Answer): Endometrial cancer is the most common primary malignancy