Protocol for the Detection of Organoid-Initiating Cell Activity in Patient-Derived Single Fallopian Tube Epithelial Cells

Identification of serous tubal intraepithelial carcinomas (STIC) in the fallopian tubes of women who are carriers of germ line pathogenic variants in tubo-ovarian cancer predisposition genes (i.e., BRCA1 and BRCA2) has led to the hypothesis that many high-grade serous carcinomas (HGSC) arise from the fimbria of the fallopian tube. However, the primitive (stem and progenitor) tubal epithelial cells that give rise to STIC and HGSC have not been defined. Further, as putative HGSC precursors are discovered at salpingectomy, the natural history of such lesions is truncated at diagnosis. Thus, living cultures of human fallopian tubes suitable for experimental studies are needed to define and characterize the cellular origin of HGSCs and thereby advance the discovery of improved methods to assess risk, develop effective early detection tests and identify novel prevention approaches. Accordingly, patient-derived tissue-organoids and isolated epithelial stem cell derived-organoids generated from average and high-risk patients are vital resources to understand the developmental biology of aging fallopian tubes and pathogenesis of HGSCs. With a vision to boost HGSC prevention research, we have established state-of-the-art protocols for the collection, processing, storage, distribution, and management of fallopian tube tissues. Here we describe the protocol for preparing these organoids, with emphasis on the key steps that require meticulous attention to achieve success.

Protocol for the Detection of Organoid-Initiating Cell Activity in Patient-Derived Single Fallopian Tube Epithelial Cells

Identification of serous tubal intraepithelial carcinomas (STIC) in the fallopian tubes of women who are carriers of germ line pathogenic variants in tubo-ovarian cancer predisposition genes (i.e., BRCA1 and BRCA2) has led to the hypothesis that many high-grade serous carcinomas (HGSC) arise from the fimbria of the fallopian tube. However, the primitive (stem and progenitor) tubal epithelial cells that give rise to STIC and HGSC have not been defined. Further, as putative HGSC precursors are discovered at salpingectomy, the natural history of such lesions is truncated at diagnosis. Thus, living cultures of human fallopian tubes suitable for experimental studies are needed to define and characterize the cellular origin of HGSCs and thereby advance the discovery of improved methods to assess risk, develop effective early detection tests and identify novel prevention approaches. Accordingly, patient-derived tissue-organoids and isolated epithelial stem cell derived-organoids generated from average and high-risk patients are vital resources to understand the developmental biology of aging fallopian tubes and pathogenesis of HGSCs. With a vision to boost HGSC prevention research, we have established state-of-the-art protocols for the collection, processing, storage, distribution, and management of fallopian tube tissues. Here we describe the protocol for preparing these organoids, with emphasis on the key steps that require meticulous attention to achieve success.

Salpingectomy for the Risk Reduction of Ovarian Cancer: Is It Time for a Salpingectomy-alone Approach?

OBJECTIVE

To summarize published evidence supporting current strategies for the prevention of epithelial ovarian cancer in women with a genetic, elevated risk for the development of this disease, as well as the emerging data on the novel salpingectomy with delayed oophorectomy (SDO) strategy. Furthermore, we will explore whether salpingectomy alone is a viable risk-reducing strategy for these women. We will also discuss current national guidelines for risk-reducing surgery based on patients' individual genetic predisposition.

DATA SOURCES

MEDLINE, PubMed, EMBASE, and the Cochrane Database, with a focus on randomized controlled trials and large prospective, observational studies.

METHODS OF STUDY SELECTION

The key search terms for our review included Medical Subject Headings: "salpingectomy," "ovarian cancer," and "risk-reducing surgery."

TABULATION, INTEGRATION, AND RESULTS

The fallopian tube is now well established as the site of origin for most ovarian cancers, particularly high-grade serous carcinomas. This finding has led to the development of new preventive surgical techniques, such as SDO, which may be associated with fewer side effects. However, until the results of ongoing trials are reported and the impact of SDO on ovarian cancer risk reduction is established, it should not be recommended outside of clinical trials, and bilateral salpingo-oophorectomy remains the treatment of choice for risk-reducing surgery, especially in women with a genetic, high risk for ovarian cancer.

CONCLUSION

The decision to undergo risk-reducing surgery among women with an elevated risk for ovarian cancer should be made after comprehensive consultation and individually based on genetic predisposition, childbearing status, and personal preference.

Cytology material is equivalent to tumor tissue in determining mutations of BRCA 1/2 genes in patients with tubo-ovarian high grade serous carcinoma

Background

High-grade serous ovarian cancer is a detrimental disease. Treatment options in patients with a recurrent disease are dependent on BRCA1/2 mutation status since only patients with known BRCA mutation are eligible for treatment with poly(ADP-ribose) polymerase inhibitors (PARPi). The aim of this study was to compare concordance of BRCA mutation analyses from cytological samples (CS) with BRCA mutation analyses from histological formalin fixed paraffin embedded (FFPE) samples.

Methods

Mutation analysis of BRCA1 and BRCA2 genes was performed in 44 women diagnosed with primary or recurrent high-grade ovarian cancer from three different samples: blood, cytological sample (ascites, pleural effusion and enlarged lymph nodes) and tumor tissue. Results from all three samples were compared.

Results

Among 44 patients, there were 15 germline mutations and two somatic mutations. A 100% concordance was found between cytological and histologic samples.

Conclusion

There is a 100% concordance in BRCA mutation testing between cytological and histologic samples. BRCA mutation testing from CS could replace testing from FFPE tissue in clinical decision making in ovarian cancer patients.

Trial registration

The study was retrospectively registered at ISRCTN registry on 24/11/2015 - ISRCTN42408038.