A 58-year-old postmenopausal woman presents with abnormal uterine bleeding for 3 months. Transvaginal ultrasound shows an endometrial thickness of 12 mm with heterogeneous echotexture. What is the investigation of choice to establish a definitive diagnosis?

Explanation

## Investigation of Choice for Endometrial Pathology **Key Point:** Endometrial biopsy via hysteroscopy is the gold standard for definitive diagnosis of endometrial carcinoma. It provides direct visualization of the endometrial cavity and allows tissue sampling for histopathological examination. ### Why Hysteroscopy with Endometrial Biopsy? **High-Yield:** Hysteroscopy offers: - Direct visualization of the endometrial cavity and any suspicious lesions - Ability to obtain multiple tissue samples from different sites - Assessment of extent of disease within the uterus - Simultaneous therapeutic intervention if needed (e.g., removal of polyps) - Sensitivity >90% for detecting endometrial malignancy ### Clinical Pearl: In postmenopausal women with abnormal bleeding and thickened endometrium (>5 mm), endometrial biopsy is indicated. Hysteroscopy allows the clinician to visualize the lesion and obtain tissue under direct visualization, making it superior to blind biopsy techniques. ### Comparison of Diagnostic Modalities | Investigation | Sensitivity | Specificity | Role | |---|---|---|---| | Transvaginal ultrasound | 60–80% | 50–60% | Screening tool | | Endometrial biopsy (blind) | 80–90% | High | Diagnosis (without visualization) | | Hysteroscopy + biopsy | >90% | >95% | Gold standard (visualization + tissue) | | MRI pelvis | 70–85% | 75–85% | Staging, not diagnosis | | Pap smear | <50% | Variable | Cervical pathology only | **Mnemonic:** **HYSTER** = **HY**steroscopy for **S**uspected **TER**itorial (endometrial) pathology — direct visualization + biopsy = diagnosis. ### Timing and Indications 1. Any postmenopausal bleeding with endometrial thickness >5 mm 2. Premenopausal abnormal uterine bleeding refractory to medical management 3. Thickened endometrium on imaging with risk factors (obesity, diabetes, unopposed estrogen) 4. Follow-up of atypical endometrial hyperplasia **Clinical Pearl:** Hysteroscopy is both diagnostic AND therapeutic — polyps can be removed, curettage performed, and tissue obtained in a single procedure.