L10 – Gynaecopathology: Genetics-Driven Cancers of the Ovary and Fallopian Tube Flashcards
What are the key anatomical features of the ovary?
The ovary consists mainly of stromal cells that support maturing germ cells and is covered by a monolayer of modified mesothelium (the ovarian surface epithelium).
How is ovarian histology significant in tumour development?
The ovarian surface epithelium, though mesothelial in origin, can undergo metaplasia to a Müllerian phenotype, giving rise to epithelial tumours.
What is the epidemiological trend of ovarian cancer?
Ovarian cancer is the eighth most common cancer in women, with significant geographical variation and a declining incidence in some areas.
Which factors are protective against ovarian cancer?
Protective factors include contraceptive pill use, high parity, breastfeeding, tubal ligation, and hysterectomy.
What are important risk factors for ovarian cancer?
Risk factors include family history, BRCA1/2 mutations, endometriosis, and certain hereditary syndromes (e.g. Lynch syndrome, Peutz-Jeghers).
How were ovarian epithelial tumours traditionally classified?
They were classified based on histological similarity to Müllerian epithelia, with categories including serous, endometrioid, clear cell, and mucinous tumours.
What is the traditional view of the cell of origin for ovarian tumours?
The traditional view posits that tumours originate from the ovarian surface epithelium undergoing metaplasia.
Why has the paradigm of ovarian tumour origin shifted recently?
New evidence suggests that many high-grade serous carcinomas may originate in the fallopian tube, as shown by precursor lesions like STIC.
What are the histological features of low-grade serous carcinoma?
They exhibit micropapillary or cribriform patterns, minimal cytological atypia, and generally have a more indolent course.
How is high-grade serous carcinoma characterised?
It features marked nuclear pleomorphism, high mitotic index, complex papillary structures, and is often associated with p53 mutations.
What is the typical clinical presentation of serous carcinomas?
They often present in postmenopausal women and may be bilateral, with high-grade tumours showing rapid progression.
How do molecular alterations differ between low- and high-grade serous carcinomas?
Low-grade tumours show fewer mutations, while high-grade tumours frequently harbour TP53 mutations and display genomic instability.
What new evidence has emerged regarding the origin of high-grade serous carcinoma?
Studies indicate that many such tumours originate from the fallopian tube epithelium, with precursor lesions identified at the fimbrial end.
How does tubal ligation affect ovarian cancer risk?
Tubal ligation has been shown to reduce the incidence of high-grade serous and other ovarian carcinomas by interrupting the proposed seeding from the fallopian tube.
What are the clinical implications of the shift in tumour origin paradigms?
It may lead to revised screening strategies, risk-reducing procedures, and tailored therapies for ovarian and tubal cancers.
Why is genetic profiling important in managing ovarian cancer?
Genetic profiling helps identify BRCA mutations and other molecular alterations, which can guide targeted therapies and inform prognosis.
What clinical impact do BRCA1/2 mutations have on ovarian cancer management?
They increase risk, guide decisions on prophylactic surgeries, and indicate suitability for PARP inhibitors.
How does the fallopian tube hypothesis influence ovarian cancer screening?
It suggests that early detection should also target the fallopian tubes, potentially altering diagnostic protocols.
What role do tumour markers such as CA-125 play in ovarian cancer?
They assist in screening, monitoring treatment response, and may help indicate recurrence, though specificity is limited.
How does histological heterogeneity in ovarian tumours affect treatment planning?
Diverse subtypes necessitate tailored therapies and impact prognosis, making precise classification crucial.
What is the anatomical relationship between the ovaries and fallopian tubes?
The ovaries are located bilaterally in the pelvis, positioned near the fallopian tubes to allow for ovum capture.
How does the fallopian tube facilitate fertilization?
The fimbrial end of the fallopian tube opens to guide the ovum toward the uterine cavity, where fertilization typically occurs.
What complications can arise from infections affecting the fallopian tubes?
Infections can cause adhesions, leading to infertility or an increased risk of ectopic pregnancy.
Why is an ectopic pregnancy a medical emergency?
An ectopic pregnancy can rupture the fallopian tube, causing severe abdominal pain and internal bleeding, necessitating urgent medical intervention.
How does polycystic ovarian syndrome affect ovarian size?
Polycystic ovarian syndrome can cause ovarian enlargement due to the accumulation of multiple immature follicles.
What are the key structural components of the ovary?
The ovary consists of an outer cortex containing developing oocytes and a deeper medulla that supports vascular structures.
How does the mesothelial lining of the ovary compare to other body surfaces?
The ovarian mesothelium is similar to that of the chest wall, providing a protective but functionally significant covering.
Why is ovarian cancer often diagnosed at an advanced stage?
Ovarian cancer remains asymptomatic in early stages, leading to late-stage detection and poorer outcomes.
How have recent classification updates changed the categorization of ovarian tumors?
Some previously malignant ovarian tumors are now classified as borderline, reflecting a less aggressive clinical course.
What genetic factors increase the risk of ovarian cancer?
BRCA1 and BRCA2 mutations, as well as Lynch syndrome, significantly elevate the risk of ovarian cancer.
Which protective factors help reduce ovarian cancer risk?
Contraceptive use, high parity, and surgical procedures such as tubal ligation help reduce ovarian cancer risk.
Why is imaging becoming more important in ovarian tumor detection?
Advanced imaging techniques are improving the early detection of ovarian tumors, even in asymptomatic cases.
How do low-grade and high-grade serous carcinomas differ in prognosis?
Low-grade serous carcinoma has a more indolent course, while high-grade serous carcinoma tends to be aggressive with a poorer prognosis.
What histological features distinguish low-grade from high-grade serous carcinoma?
Low-grade serous carcinoma shows a papillary growth pattern with minimal atypia, whereas high-grade serous carcinoma exhibits significant cellular atypia, high mitotic activity, and invasive behavior.
How does BRCA mutation status impact ovarian cancer treatment?
BRCA mutations guide treatment decisions, particularly the use of targeted therapies such as PARP inhibitors.
Why is the classification of ovarian tumors evolving over time?
Ongoing research and genetic discoveries are refining tumor classification and influencing treatment strategies.
