Recommendations for diagnosing STIC: a systematic review and meta-analysis

Our understanding of the oncogenesis of high-grade serous cancer of the ovary and its precursor lesions, such as serous tubal intraepithelial carcinoma (STIC), has significantly increased over the last decades. Adequate and reproducible diagnosis of these precursor lesions is important. Diagnosing STIC can have prognostic consequences and is an absolute requirement for safely offering alternative risk reducing strategies, such as risk reducing salpingectomy with delayed oophorectomy. However, diagnosing STIC is a challenging task, possessing only moderate reproducibility. In this review and meta-analysis, we look at how pathologists come to a diagnosis of STIC. We performed a literature search identifying 39 studies on risk reducing salpingo-oophorectomy in women with a known BRCA1/2 PV, collectively reporting on 6833 patients. We found a pooled estimated proportion of STIC of 2.8% (95% CI, 2.0–3.7). We focused on reported grossing protocols, morphological criteria, level of pathologist training, and the use of immunohistochemistry. The most commonly mentioned morphological characteristics of STIC are (1) loss of cell polarity, (2) nuclear pleomorphism, (3) high nuclear to cytoplasmic ratio, (4) mitotic activity, (5) pseudostratification, and (6) prominent nucleoli. The difference in reported incidence of STIC between studies who totally embedded all specimens and those who did not was 3.2% (95% CI, 2.3–4.2) versus 1.7% (95% CI, 0.0–6.2) (p 0.24). We provide an overview of diagnostic features and present a framework for arriving at an adequate diagnosis, consisting of the use of the SEE-FIM grossing protocol, evaluation by a subspecialized gynecopathologist, rational use of immunohistochemical staining, and obtaining a second opinion from a colleague.

Tubal histopathological abnormalities in BRCA1/2 mutation carriers undergoing prophylactic salpingo-oophorectomy: a case–control study

ObjectiveTo describe tubal histopathological abnormalities in women with germline BRCA1/2 mutations and in controls.MethodsConsecutive women with BRCA1/2 mutations undergoing bilateral salpingo-oophorectomy between 2010 and 2020 in two centers (San Gerardo Hospital, Monza and San Matteo Hospital, Pavia) were considered in this analysis and compared with controls who had the same surgical procedure for benign conditions. Frequency of p53 signature, serous tubal intraepithelial carcinoma, and high-grade serous ovarian cancer were compared between the two groups.ResultsA total of 194 women with pathogenic BRCA1/2 mutations underwent prophylactic salpingo-oophorectomy. Of these, 138 women (71%) had a completely negative histological examination, while in 56 (29%) patients an ovarian or tubal alteration was reported. Among controls, 84% of patients had a p53wt signature, while 16% had a p53 signature. There was no difference in the frequency of a p53 signature between cases and controls; however, women with BRCA1/2 mutations were more likely to have pre-malignant or invasive alterations of tubal or ovarian epithelium (p=0.015). Among mutation carriers, older age both at genetic testing and at surgery was associated with an increased risk of having malignancies (OR=1.07, p=0.006 and OR=1.08, p=0.004, respectively). The risk of malignancy seems to be increased in patients with a familial history of high-grade serous ovarian cancer. Previous therapy with tamoxifen was significantly more frequent in patients with malignant lesions (40.0% vs 21.3%, p=0.006).ConclusionWe found that a p53 signature is a frequent finding both in BRCA1/2 mutation carriers and in controls, while pre-invasive and invasive lesions are more frequent in BRCA1/2 mutation carriers. Genetic and clinical characteristics are likely to affect the progression to malignancy.

A case of synchronous serous ovarian cancer and uterine serous endometrial intraepithelial carcinoma

Background Serous endometrial intraepithelial carcinoma (SEIC) is now considered to represent an early stage of uterine serous carcinoma (USC). It is an intraepithelial lesion but has been reported to cause extrauterine metastases. We report a case of SEIC with serous ovarian carcinoma and lymph node metastasis. Case presentation A 57-year-old post-menopausal woman (gravida 3, para 2, SA1) was referred to our hospital with lower abdominal pain. An ultrasound and MRI showed that the ovary had swollen to 8 cm in size and had a solid lesion. The uterus was normal. The patient underwent exploratory laparoscopy on the suspicion of torsion of the ovarian tumor. Intraoperative findings showed a right ovarian tumor, but no ovarian tumor torsion was observed. A small amount of bloody ascites was found in the Douglas fossa, and bleeding was observed from the tumor itself. A right salpingo-oophorectomy was then performed. Histopathological results revealed a high-grade serous carcinoma. Forty days after the first surgery, we performed a staging laparotomy: a total abdominal hysterectomy, left salpingo-oophorectomy, systematic pelvic and paraaortic lymphadenectomy, and a partial omentectomy. A complete cytoreduction was achieved. In the pathological examination, the invasion of the serous carcinoma was observed in the left ovarian ligament, and lymph node metastasis was found in the paraaortic lymph nodes. Atypical columnar cells formed irregular papillary lesions which had proliferated in the endometrium, and this was diagnosed as SEIC. The final diagnosis was serous ovarian cancer, FIGO stage IIIA1(ii), pT2bN1M0, with SEIC. Conclusion We report a case of SEIC with synchronous serous carcinoma of the adnexa uteri. Both were serous carcinomas and, thus, it was difficult to identify the primary lesion. The distinction between metastatic cancer and two independent primary tumors is important for an accurate diagnosis and tumor staging. Histological diagnostic criteria remain controversial, and further development of a method for differentiating between both diseases is required.

A Case of Synchronous Serous Ovarian Cancer and Uterine Serous Endometrial Intraepithelial Carcinoma

BackgroundSerous endometrial intraepithelial carcinoma (SEIC) is now considered to represent an early stage of uterine serous carcinoma (USC). It is an intraepithelial lesion but has been reported to cause extrauterine metastases. We report a case of SEIC with serous ovarian carcinoma and lymph node metastasis.Case presentationA 57-year-old post-menopausal woman (gravida 3, para 2, SA1) was referred to our hospital with lower abdominal pain. An ultrasound and MRI showed that the ovary had swollen to 8 cm in size and had a solid lesion. The uterus was normal. The patient underwent exploratory laparoscopy on the suspicion of torsion of the ovarian tumor. Intraoperative findings showed a right ovarian tumor, but no ovarian tumor torsion was observed. A small amount of bloody ascites was found in the Douglas fossa, and bleeding was observed from the tumor itself. A right salpingo-oophorectomy was then performed. Histopathological results revealed a high-grade serous carcinoma. Forty days after the first surgery, we performed a staging laparotomy: a total abdominal hysterectomy, left salpingo-oophorectomy, systematic pelvic and paraaortic lymphadenectomy, and a partial omentectomy. A complete cytoreduction was achieved. In the pathological examination, the invasion of the serous carcinoma was observed in the left ovarian ligament, and lymph node metastasis was found in the paraaortic lymph nodes. Atypical columnar cells formed irregular papillary lesions which had proliferated in the endometrium, and this was diagnosed as SEIC. The final diagnosis was serous ovarian cancer, FIGO stage ⅢA1(ⅱ), pT2bN1M0, with SEIC. ConclusionWe report a case of SEIC with synchronous serous carcinoma of the adnexa uteri. Both were serous carcinomas and, thus, it was difficult to identify the primary lesion. The distinction between metastatic cancer and two independent primary tumors is important for an accurate diagnosis and tumor staging. Histological diagnostic criteria remain controversial, and further development of a method for differentiating between both diseases is required.