OG34.1 | Endometrial Cancer — Summary & Reflection

KEY TAKEAWAYS

Endometrial cancer is the most common gynaecological malignancy in high-income settings and presents in ~90% of cases with postmenopausal bleeding. It has two biological types: Type I (~80%, endometrioid, oestrogen-driven via the hyperplasia pathway, Grade 1/2, PTEN mutations, good prognosis) and Type II (~20%, serous/clear cell/carcinosarcoma, not oestrogen-driven, TP53 mutations, poor prognosis). Key risk factors for Type I include obesity, nulliparity, late menopause, tamoxifen use, and diabetes. Investigations: TVUS (ET >4 mm = biopsy needed), Pipelle endometrial biopsy (99% sensitivity), MRI pelvis (myometrial invasion depth), CT/PET-CT (nodal/distant). FIGO 2023 staging (entirely different from cervical cancer staging): IA = myometrial invasion <50%; IB = ≥50%; II = cervical stromal invasion; IIIA = serosa/adnexa; IIIB = vagina/parametria; IIIC1/IIIC2 = pelvic/para-aortic nodes; IVA = bladder/bowel mucosa; IVB = distant. Primary treatment is staging laparotomy (TAH+BSO+pelvic and para-aortic lymphadenectomy+peritoneal washings). Adjuvant therapy by risk: low risk = observation; intermediate = vaginal brachytherapy (PORTEC-2); high risk/Type II/Stage III = concurrent chemoradiation; Stage IVB = carboplatin/paclitaxel ± pembrolizumab. Lynch syndrome women have 40–60% lifetime risk and require annual endometrial surveillance from age 30–35.

REFLECT

Return to the woman at the start of this module. She is 64, obese, diabetic, hypertensive, and now has Stage IA (myometrial invasion 40%, <50%) Grade 1 endometrioid endometrial cancer. She will undergo a total abdominal hysterectomy + BSO + lymph node dissection. Her final pathology, if confirming IA G1 with no lymphovascular space invasion, will place her in the low-risk category — she will need no adjuvant therapy, and her 5-year survival exceeds 90%. Now consider a thought experiment: if she had been diagnosed with a Grade 3 tumour with 70% myometrial invasion and two positive pelvic lymph nodes (Stage IIIC1), the same surgery would be followed by concurrent chemoradiation, and her 5-year survival would drop to approximately 50–60%. Both scenarios start with the same presenting complaint — postmenopausal bleeding — detected at different points in the disease's natural history. What does this imply for the importance of investigating postmenopausal bleeding promptly, and for reducing barriers to accessing urgent gynaecology clinics for postmenopausal women in India?