Endometrial Cancer: Diagnosis and Treatment Pathway

Endometrial cancer is the second most common gynaecological malignancy in China, and its incidence is rising with obesity and diabetes. The encouraging news is that about 70% of cases are found while the tumour is still confined to the uterus, when cure rates are high. Roughly 90% of patients first notice irregular vaginal bleeding — most often after menopause — or an abnormal watery or blood-tinged discharge. Perimenopausal women may notice heavier periods, prolonged bleeding or spotting between periods. This guide summarises how the diagnosis is made and how treatment is planned, based on the 2021 guideline of the Chinese Society of Gynecologic Oncology.

Recognising the warning signs

Any bleeding after menopause deserves evaluation, even light spotting. Before menopause, report periods that become persistently heavier, longer, or irregular. Benign conditions such as endometrial polyps and hyperplasia cause similar symptoms, so bleeding is a reason to be checked — not a reason to panic. Risk factors include long-standing unopposed oestrogen exposure (for example oestrogen-only therapy or tamoxifen), obesity, diabetes, never having given birth, late menopause and, in about 5% of patients, inherited syndromes — most importantly Lynch syndrome, which also raises colorectal and ovarian cancer risk.

How the diagnosis is confirmed

The gold standard is a pathologist examining a sample of the endometrium. Sampling is done in the clinic with a thin suction pipette, or by dilation and curettage, often under hysteroscopy so the whole cavity is visualised. Because lesions can be patchy, a negative biopsy misses cancer in about 10% of suspicious cases — if clinical concern persists, the sampling is repeated or hysteroscopy performed. Transvaginal ultrasound is the usual first imaging test; contrast-enhanced MRI is the most accurate way to measure how deeply the tumour invades the muscle wall; a chest CT completes baseline staging, and PET-CT is reserved for suspected spread. Blood markers CA125 and HE4 are not diagnostic but can help monitor advanced disease. Importantly, the Chinese guideline recommends that pathology slides from outside hospitals be re-reviewed by the treating centre — international patients should always bring their original slides and blocks.

Molecular typing: why it is changing treatment

Since the WHO 2020 update, endometrial cancer is classified not only by appearance but by molecular features: POLE-ultramutated tumours (excellent prognosis — stage I–II patients may avoid additional treatment after surgery), mismatch-repair-deficient/MSI-high tumours (intermediate prognosis, sensitive to immunotherapy), NSMP/MSS tumours (hormone-sensitive, relevant for younger patients) and p53-mutant tumours (worst prognosis, more chemo-sensitive). The guideline recommends screening every endometrial cancer — at minimum everyone diagnosed under 60, or with a suggestive family history — for Lynch syndrome using MMR immunohistochemistry or MSI testing, because it changes surveillance for the patient and screening advice for the family.

Surgery: the cornerstone

Standard treatment for disease confined to the uterus is total hysterectomy with removal of both tubes and ovaries, usually by minimally invasive surgery, together with peritoneal washings. Removal of pelvic and para-aortic lymph nodes may be replaced in suitable patients by sentinel lymph node mapping, which causes far less leg swelling. Younger patients with carefully selected grade-1 endometrioid cancer limited to the endometrium, who strongly wish to preserve fertility, can be treated with high-dose progestins or a progestin intrauterine device, with endometrial sampling every 3–6 months — but this is a monitored pathway, not a guarantee, and hysterectomy is recommended once childbearing is complete.

Adjuvant therapy and advanced disease

After surgery, treatment is tailored to risk group. Low-risk patients need no additional therapy. Intermediate-risk patients often receive vaginal brachytherapy — short internal radiotherapy courses that minimise exposure. High-intermediate and high-risk patients receive pelvic radiotherapy and/or chemotherapy, with carboplatin plus paclitaxel the standard combination. For advanced or recurrent disease, molecular results guide targeted options: trastuzumab for HER2-positive serous cancer, pembrolizumab or nivolumab for MSI-high or dMMR tumours, lenvatinib plus pembrolizumab after prior chemotherapy, and hormone therapy (progestins, aromatase inhibitors) for slow-growing receptor-positive disease.

Follow-up

Most recurrences appear within three years. Expect a review every 3–6 months for the first 2–3 years, six-monthly to five years, then annually — including symptom review, examination and selected blood tests or imaging. Weight management, diabetes control and an active lifestyle are part of the plan, not an afterthought: they influence both recurrence risk and overall health.