The Special Issue on high grade serous ovarian cancer (HGSOC) and the contribution of the tumor microenviroment (TME) consists of reviews contributed by leaders in the OC field. As HGSOC metastases ...have a highly complex TME, there is an urgent need to better understand the TME in general, its distinct components in particular, and the role of the TME in the context of disease recurrence and development of chemoresistance. The Special Issue incorporates the current understanding of the different parts of thd TME components, including the cancer cells themselves, the cells surrounding the cancer cells or stromal cells, and the cells of the immune system, which are attracted to the site of metastases. In addition to these cells of the TME, the role of various cellular factors made by the cells of the TME are also the subject of the reviews. In addition, reviews in this Special Issue cover the complex relationships between the molecular mechanisms of HGSOC progression, including genomic, epigenomic and transcriptomic changes and changes in the immune cell landscape, as these may provide attractive new molecular targets for HGSOC therapy.
Ovarian carcinoma (OC) is an umbrella term for multiple distinct diseases (histotypes), each with their own developmental origins, clinical behaviour and molecular profile. Accordingly, OC management ...is progressing away from a one-size-fits all approach, toward more molecularly-driven, histotype-specific management strategies. Our knowledge of driver events in high grade serous OC, the most common histotype, has led to major advances in treatments, including PARP inhibitor use. However, these agents are not suitable for all patients, most notably for many of those with rare OC histotypes. Identification of additional targeted therapeutic strategies will require a detailed understanding of the molecular landscape in each OC histotype. Until recently, tumour profiling studies in rare histotypes were sparse; however, significant advances have been made over the last decade. In particular, reports of genomic characterisation in endometrioid, clear cell, mucinous and low grade serous OC have significantly expanded our understanding of mutational events in these tumour types. Nonetheless, substantial knowledge gaps remain. This review summarises our current understanding of each histotype, highlighting recent advances in these unique diseases and outlining immediate research priorities for accelerating progress toward improving patient outcomes.
•Ovarian cancer comprises multiple distinct disease types.•Each ovarian cancer type has unique clinical and molecular features.•Substantial advances have been made in our understanding of rare ovarian cancers.•Molecular understanding has led to targeted therapies for some ovarian cancers.•Significant gaps remain in our understanding of rare ovarian cancers.
Breast cancer is a common cancer affecting a large number of patients. Notably, 5–10% of all breast cancer patients are genetically predisposed to cancers. Although the most common breast cancer ...susceptibility genes are
BRCA1
and
BRCA2
, which are also associated with the risk of developing ovarian and pancreatic cancer, advances in next-generation sequencing (NGS) analysis technology enabled the discovery of several non-
BRCA
genes responsible for breast and ovarian cancers. Studies on hereditary breast and ovarian cancer (HBOC) involve not only determining the predisposition to developing cancer, but also considering the current treatment for breast cancer, prevention of next cancer, risk diagnosis, and adoption of protective measures for relatives. We present a comprehensive review of HBOC, which will be a useful resource in the clinical setting. Many hereditary tumors, including HBOC, are syndromes characterized by the development of different types of cancer in succession. Taking advantage of knowing predisposition of susceptibility to cancer, it is important to continue and update cancer management protocols, which includes the adoption of preventive measures, countermeasures, and treatments, to accurately assess and prevent the impact of cancer on the quality of life of the next generation of patients.
High-grade serous ovarian cancer, also known as high-grade serous carcinoma (HGSC), is the most common and deadliest type of ovarian cancer. HGSC appears to arise from the ovary, fallopian tube, or ...peritoneum. As most HGSC cases present with widespread peritoneal metastases, it is often not clear where HGSC truly originates. Traditionally, the ovarian surface epithelium (OSE) was long believed to be the origin of HGSC. Since the late 1990s, the fallopian tube epithelium has emerged as a potential primary origin of HGSC. Particularly, serous tubal intraepithelial carcinoma (STIC), a noninvasive tumor lesion formed preferentially in the distal fallopian tube epithelium, was proposed as a precursor for HGSC. It was hypothesized that STIC lesions would progress, over time, to malignant and metastatic HGSC, arising from the fallopian tube or after implanting on the ovary or peritoneum. Many clinical studies and several mouse models support the fallopian tube STIC origin of HGSC. Current evidence indicates that STIC may serve as a precursor for HGSC in high-risk women carrying germline
or
mutations. Yet not all STIC lesions appear to progress to clinical HGSCs, nor would all HGSCs arise from STIC lesions, even in high-risk women. Moreover, the clinical importance of STIC remains less clear in women in the general population, in which 85⁻90% of all HGSCs arise. Recently, increasing attention has been brought to the possibility that many potential precursor or premalignant lesions, though composed of microscopically-and genetically-cancerous cells, do not advance to malignant tumors or lethal malignancies. Hence, rigorous causal evidence would be crucial to establish that STIC is a bona fide premalignant lesion for metastatic HGSC. While not all STICs may transform into malignant tumors, these lesions are clearly associated with increased risk for HGSC. Identification of the molecular characteristics of STICs that predict their malignant potential and clinical behavior would bolster the clinical importance of STIC. Also, as STIC lesions alone cannot account for all HGSCs, other potential cellular origins of HGSC need to be investigated. The fallopian tube stroma in mice, for instance, has been shown to be capable of giving rise to metastatic HGSC, which faithfully recapitulates the clinical behavior and molecular aspect of human HGSC. Elucidating the precise cell(s) of origin of HGSC will be critical for improving the early detection and prevention of ovarian cancer, ultimately reducing ovarian cancer mortality.