Cancers associated with extraovarian endometriosis at less common/rare sites: A nationwide survey in Japan

Masaki Mandai, Yutaka Osuga, Tetsuya Hirata, Takayuki Enomoto, Hidekatsu Nakai, Ritsuo Honda, Fuminori Taniguchi, Hidetaka Katabuchi
Journal of Obstetrics and Gynaecology Research · 2020 · vol. 46(6) , pp. 917–923 · doi:10.1111/jog.14244 · PMID:32212420 · W3013142600
article OA: closed CC0 ⤵ 11 in-corpus citations
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This nationwide survey identified 11 rare site endometriosis-associated cancers, predominantly of endometrioid histology, arising from intestinal, urinary tract, and umbilical endometriosis.

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Abstract

AIM: Endometriosis mostly affects the ovary but can also be present outside of the ovary including the pelvic peritoneum, intestine, urinary tract and lung. In case of ovarian endometriotic cyst, an increased risk of ovarian cancer, especially of clear cell and endometrioid histology, has been reported. However, because of the rarity, cancer occurrence from endometriosis at less common sites/rare sites is poorly understood. METHODS: We conducted a nationwide survey on the less common/rare site endometriosis in 3539 authorized facilities in Japan. We requested to complete a case report form for each case, including information on the history of endometriosis, treatment for endometriosis, type of surgery, involved site(s) of cancer and endometriosis, histology of cancer, chemotherapy and outcome. RESULTS: Out of 1397 confirmed cases of less common/rare site endometriosis, 11 cases of rare site endometriosis-associated cancer (RSEAC) were reported: seven of them were associated with intestinal endometriosis, three were associated with urinary tract endometriosis and one was associated with umbilical endometriosis. Interestingly, the histology was endometrioid in seven (64%) cases, and serous, seromucinous borderline, clear cell and mucinous in one case each (10%), differing from the case of ovarian endometriosis-associated cancer, in which clear cell carcinoma are more common. CONCLUSION: Our nationwide survey on RSEAC has revealed that: (i) the incidence of malignant transformation may be lower than ovarian endometriosis, (ii) malignant transformation from endometriosis outside the abdominal cavity may be extremely rare and (iii) the histology of RSEAC is predominantly endometrioid type, suggesting an association of a hormonal effect.

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Condition tags

mesh:D004715endometriosis

MeSH descriptors

Cell Transformation, Neoplastic Endometriosis Adenocarcinoma, Clear Cell Adenocarcinoma, Clear Cell Adult Carcinoma, Endometrioid Carcinoma, Endometrioid Endometrial Neoplasms Endometrial Neoplasms Endometriosis Endometriosis Female Humans Incidence Japan Japan Middle Aged Ovarian Neoplasms Ovarian Neoplasms Surveys and Questionnaires

Citation neighborhood

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References (20)

Cited by (11)

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