A 68-year-old postmenopausal woman has a well-circumscribed 3 cm breast mass. Biopsy shows islands and nests of tumor cells floating in large pools of extracellular mucin. The tumor cells are ER positive and PR positive. Which statement about this tumor is correct?
- A It has a high rate of axillary lymph node metastasis
- B It is almost always HER2 amplified
- C It carries a better prognosis than invasive carcinoma of no special type ✓
- D It is typically triple negative
Correct answer: C. It carries a better prognosis than invasive carcinoma of no special type
Explanation
Pure mucinous (colloid) carcinoma shows clusters of low-grade cells in abundant extracellular mucin and is typically ER and PR positive with low proliferation. Axillary involvement and distant spread occur less often than in carcinomas of no special type, giving it a distinctly better prognosis. It is usually HER2 negative, which eliminates both the HER2-amplified and triple-negative options.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.