A 35-year-old woman with endometriosis undergoes laparoscopy. Ectopic endometrial implants are found on the ovary forming a 'chocolate cyst' (endometrioma). The brown color of the cyst content is due to:
- A Hemosiderin and old blood from repeated cyclic hemorrhage within the cyst ✓
- B Accumulated bile pigment from hepatic dysfunction
- C Melanin produced by ectopic endometrial cells
- D Melanocyte-stimulating hormone induced pigmentation of the ovarian stroma
Correct answer: A. Hemosiderin and old blood from repeated cyclic hemorrhage within the cyst
Explanation
Endometriomas ('chocolate cysts') of the ovary are formed when ectopic endometrial tissue undergoes cyclic bleeding in response to hormonal stimuli, accumulating old blood within the cyst cavity. The dark brown, thick, tar-like contents result from hemosiderin (iron-storage protein) and breakdown products of old blood (methemoglobin, bilirubin) from repeated hemorrhagic episodes. Bile pigment, melanin, and MSH are not involved in this process.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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