Significant risk factors for malignant transformation of ovarian endometrioma during dienogest treatment: a case report and retrospective study

Abstract

BackgroundTo determine the prevalence of and risk factors for malignant transformation of ovarian endometrioma during dienogest therapy, which is very rare, we examined multiple cases of malignant transformation of ovarian endometrioma during dienogest therapy and performed a multivariate analysis of the records in our hospital.MethodsThe medical records of 174 patients who underwent DNGT for the treatment of OMA from June 1, 2011, to May 31, 2018, were reviewed retrospectively with the approval of the Human Ethical Committee of the University of Teikyo Hospital. And we provided one representative case of MT with obtaining written informed consent. To assess the effects of six representative factors, including advanced age, parity, surgical history, and endometrial cyst characteristics (including 3 factors), on the possibility of malignant transformation, we performed a multivariate logistic regression analysis.ResultsOf the 174 cases, 4 were diagnosed with malignant transformation, and these cases are reported. In the multivariate analysis, advanced age (P = 0.0064), nullipara (P = 0.0322), and enlargement (P = 0.0079) showed significant differences for malignant transformation occurrence. All 4 malignant transformation cases were among the 19 patients who had all of these 3 factors.ConclusionsFor a more accurate determination of the treatment approach, a larger sample size will be needed to determine the risk factors for malignant transformation during dienogest therapy.

Case report: Malignant transformation of ovarian endometrioma during long term use of dienogest in a young lady

“…From the Pubmed search on long-term use of dienogest, we found no report on malignant transformation of endometriosis. Only a case series of malignant transformation of endometrioma within a relatively shorter duration of dienogest was reported in Japan ( 12 ). The 4 cases with dienogest treatment were within ages from 42 to 44 years, all nullipara, and malignancy were found at 42 to 46 years old.…”

“…Pathology types were all clear cell carcinoma, staging 1C1-1C3 ( Table 1 ). They presumed characteristics for high risks of malignant transformation include advanced age, nulliparity, and recurrence with significantly growing cyst size ( 12 ). In our case, despite her younger age and longer duration of the dienogest control, and no significant change in size comparing to initial diagnosis, her malignancy still occurred at a more advanced stage.…”

“…Cases of malignancy transformation of endometriosis have been reported under the medication of dienogest. However, in those case reports, malignancy typically occurs within a relatively short time after start of dienogest treatment ( 12 ). Therefore, whether or not there were occult malignancy at the initiation of diengoest was suspicious.…”