A 15 year old boy presents was brought to OPD with a history of pain and swelling in the right thigh. Biopsy of the mass demonstrates Osteosarcoma. His mother was diagnosed with breast cancer 1 year ago and his maternal grandmother died of the breast cancer 10 years ago. The child has 3 younger siblings. Siblings are at an increased risk of developing which of the following cancer ?

**Core Concept**
The question is testing the understanding of hereditary cancer syndromes, specifically Li-Fraumeni syndrome (LFS), a rare genetic disorder characterized by an increased risk of developing multiple cancers, including breast cancer, sarcomas, and brain tumors.

**Why the Correct Answer is Right**
The presence of breast cancer in two generations (mother and grandmother) of the same family suggests an autosomal dominant pattern of inheritance, which is typical of LFS. The child's osteosarcoma further increases the suspicion of LFS, as it is one of the hallmark cancers associated with this syndrome. Individuals with LFS have a mutation in the TP53 tumor suppressor gene, which leads to a loss of function and impaired DNA repair, increasing the risk of cancer development.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because LFS is not typically associated with an increased risk of colon cancer, which is more commonly linked to Lynch syndrome.

**Option B:** This option is incorrect because LFS is not typically associated with an increased risk of ovarian cancer, which is more commonly linked to BRCA1 and BRCA2 mutations.

**Option C:** This option is incorrect because LFS is not typically associated with an increased risk of prostate cancer, which is more commonly linked to genetic mutations in the BRCA2 gene.

**Clinical Pearl / High-Yield Fact**
Individuals with LFS often develop multiple primary cancers, and the average age of cancer diagnosis is significantly lower than in the general population. This syndrome highlights the importance of genetic counseling and screening for individuals with a family history of cancer.

**Correct Answer:** B.

✓ Correct Answer: D. Glioma