Keywords
Borderline serous tumor - endometriosis - ovary
Introduction
The ovary is a common site for endometriosis. Endometriosis is the presence of endometrium glands and stroma outside the uterus.[1] It is well recognized that malignant transformation can occurs in endometriosis. Nishida et al. reported 18 cases of atypical endometriosis and one case of ovarian carcinoma in 147 cases of ovarian endometriosis, thus the incidence of malignancy in ovarian endometriosis is 0.7%.[2] However, among the malignancies, clear cell adenocarcinoma and endometrioid adenocarcinoma are the common malignancies associated with endometriosis. Serous and mucinous tumors are infrequently seen with endometriosis.[3] Here, we present a case report of a 40-year-old female who clinically presented with abnormal uterine bleeding (AUB) and ovarian mass. On histopathological examination, it was diagnosed as a borderline serous tumor with endometriosis.
Case Report
A 40-year-old female presented to the outpatient setting with AUB and abdominal mass. On ultrasonography examination, it was diagnosed as an ovarian cyst. Hysterectomy with bilateral salpingo-oophorectomy was performed, and the specimen was sent in 10% formal saline for histopathological analysis. Grossly, hysterectomy with bilateral salpingo-oophorectomy measured 12 cm × 9 cm × 6 cm, on further sectioning, multiple leiomyomas measuring 1 to 1.5 cm in size were also seen in the myometrium, [Figure 1] whereas, the left sided ovary showed hemorrhagic luteal cyst and right sided ovary measured 8 cm × 6 cm × 4 cm, which on cutting was uniloculated, with papillary architecture and filled with serous fluid [Figure 2]. On histopathology examination, right sided ovary showed a borderline serous tumor, and associated endometriosis [Figure 3] and [Figure 4].{Figure 1}{Figure 2}{Figure 3}{Figure 4}
Figure 1: Gross examination of hysterectomy showing subserosal and intra mural-leiomyoma, whereas right-sided ovary having borderline serous cystadenoma with endometriosis
Figure 2: Gross picture of right-sided ovary showing borderline serous cystadenoma with endometriosis
Figure 3: Borderline serous cystadenoma with benign endometriosis, H and E (×40)
Figure 4: Endometrial glands and its stroma lying in ovarian stroma, H and E (×100)
Discussion
Ovarian tumors are common tumors of the female genital tract. The WHO classification of ovarian tumor includes surface epithelial tumor, germ cell tumor, sex cord stromal tumour, miscellaneous and metastatic tumors.[4],[5] Surface epithelial tumor constitutes 60%–70% of all ovarian neoplasms and 90% of malignant ovarian tumors. The common epithelial tumors are serous, mucinous, and endometrioid. Serous tumors are divided into benign, borderline, and malignant.[5] Endometriosis is defined as heterotopic presence of endometrium, that is, endometrial glands with its stroma outside the endometrium. Exact pathology is not known, but some theories believe that reflux of endometrial tissue through fallopian tube at the time of menstruation, coelomic metaplasia, embryonic cell rest lymphatic and vascular dissemination have been proposed to explain the theory of endometriosis.[6] The pathogenesis is multifactorial including genetic, hormonal, environment, and role of immune system.[7] The ovary is the most common site of endometriosis followed by pelvic structures. In 1925, for the first time, Sampson explained the association between endometriosis and ovarian carcinoma.[8] Stern et al. reported that ovarian malignancies were associated with endometriosis in 3.2%–10% of cases.[9] Histologically, in majority of the patients with ovarian epithelial tumors and associated endometriosis, the ovarian tumor is of endometrioid (53%) or clear cell lineage (22%); and in most cases with associated endometriosis serous or mucinous ovarian epithelial tumors, it was more frequently borderline, which also justifies the better prognosis of ovarian epithelial tumors associated with endometriosis.[10] The present case also confirms the borderline nature of serous ovarian tumor with associated endometriosis.
The significance of endometriosis arises because of its malignant potential, pathology might be high estrogen concentration which leads to malignant proliferation of endometriotic cyst or due to mutation in the AR1D1A gene and consequent loss of BAF250a expression, similarly, iron produced in endometriotic cyst promotes oxidative stress, which causes genetic mutation and malignant progression of ovarian cyst.[11]
Conclusion
It is uncommon to find an association of borderline serous tumor with endometriosis, because the incidence is higher with clear cell and endometrioid carcinoma, but still possibilities are always there. Thus, histopathological evaluation of every ovarian mass must be carried out to determine the ovarian tumor along with the endometriosis, especially to analyze the malignant potential of endometriosis.
