TITLE:
A Case of Low-Grade Appendiceal Mucinous Neoplasm of Its Difficultly to Distinguish from a Right Ovarian Tumor Due to Postmenopause
AUTHORS:
Tsutomu Muramoto, Kyosuke Kamijo, Megumi Sano, Yuki Ibuki, Atushi Mori, Yaeko Kobayashi
KEYWORDS:
Low-Grade Appendiceal Mucinous Neoplasm, Ovarian Tumor, Menopause Woman
JOURNAL NAME:
Open Journal of Obstetrics and Gynecology,
Vol.12 No.11,
November
9,
2022
ABSTRACT: We here present a rare case of appendiceal tumor mimicking ovarian tumor in menopause woman. The patient was a 56-year-old
woman, G1P1, who presented to our hospital with a right adnexal cyst
diagnosed at another hospital. Transvaginal echocardiography showed a cyst in
the right adnexal region, and pelvic contrast-enhanced MRI revealed a small
cyst in the same region. The left ovary was atrophic and identifiable. It was
unclear whether the cyst was contiguous with the gastrointestinal tract. Blood
tests showed no elevation of tumor markers. We considered its possibility of a
gastrointestinal origin, but since right normal ovary was not found, we thought
the tumor was of ovarian origin and decided on a laparoscopic resection of the
right adnexa. Intraoperatively, we observed atrophied bilateral normal ovaries,
and the pelvic tumor was contiguous to the
appendix. Surgeons performed a laparoscopic appendectomy after consultation with us. After resection we searched
the abdominal and pelvic cavities, but found no obvious disseminated lesions.
The histological diagnosis was
low-grade appendiceal mucinous neoplasm (LAMN), a rare benign tumor of
the appendix. Appendiceal tumors can be difficult to differentiate from right
ovarian tumors due to their close anatomic location in the pelvis. It is possible to determine whether the tumor is of
ovarian or appendiceal origin by identifying normal ovaries and the location of
the feeding vessels into the tumors. In our case, there were no lesions
other than the appendix, but LAMN can metastasize to the ovary, cause
pseudomyoxoma peritonei, or be an overlapping tumor with an ovarian tumor. If
an appendiceal tumor is diagnosed after surgery for ovarian tumor, the
intra-abdominal cavity should be searched for metastasis or dissemination, and
a thorough search for ovarian lesions should be performed with the possibility
of an overlapping tumor in mind.