Background: We report a rare case of a 52-year-old woman with an initial diagnosis of mucinous adenocarcinoma of the ovary and a final finding of metastatic mixed gonadal neuroendocrine carcinoma of the appendix.
Case presentation: A 52-year-old Chinese woman was found to have a mass in the right adnexal region during a physical examination. She underwent a first exploratory laparotomy and had her right adnexa and part of her left ovary removed. Eighteen months later, the left adnexal mass recurred and she underwent a repeat exploratory laparotomy and total hysterectomy, left adnexa, greater omentum, appendectomy and pelvic lymph node dissection.
Conclusions: Mixed adeno-neuroendocrine carcinoma of appendix is a rare condition. Often, postoperative pathology is required for diagnosis. The case reported here demonstrates that mixed glandular neuroendocrine carcinoma of the appendix can take the form of ovarian cancer, which can be misdiagnosed, and should therefore be differentiated from mixed adeno-neuroendocrine carcinoma of the appendix by gynaecologists when they encounter cases of ovarian cancer.