Diagnostic Evaluation, Staging Workup, and Imaging
Overview
This domain covers the diagnostic pathway for suspected gynecologic malignancies: history, physical exam, biopsy, imaging, and laboratory tests. Key concepts: Cervical cancer: Pap smear, HPV testing, colposcopy, biopsy, and imaging (MRI for local staging, CT/PET for nodal and distant metastasis). Endometrial cancer: endometrial biopsy, transvaginal ultrasound (endometrial thickness), MRI for myometrial invasion, CT/PET for metastasis. Ovarian cancer: pelvic exam, transvaginal ultrasound, CA-125, CT abdomen/pelvis, and surgical staging. Vulvar cancer: biopsy, imaging for nodal assessment (sentinel lymph node biopsy for early-stage). Vaginal cancer: biopsy, imaging. Staging workup includes chest imaging, CBC, chemistry, and assessment of renal and hepatic function. Tumor markers: CA-125 (ovarian), HE4, CEA (mucinous), inhibin (granulosa cell), hCG (germ cell).
Traps
Questions often test the appropriate imaging modality for staging. A common trap is using MRI for cervical cancer staging (yes, for local extent) but not for ovarian (CT is preferred for staging). Another trap is the role of CA-125: it is not a screening test but useful for monitoring and distinguishing benign from malignant pelvic masses. Also, endometrial biopsy is the gold standard for endometrial cancer diagnosis, not ultrasound alone. Sentinel lymph node biopsy is standard for early vulvar cancer but not for ovarian.
Worked Example
A 45-year-old woman has a cervical biopsy showing squamous cell carcinoma. What is the next step in staging? Pelvic exam and imaging (MRI pelvis, CT chest/abdomen/pelvis or PET-CT) to determine FIGO stage. Rule of thumb: Cervical cancer staging is clinical (FIGO), but imaging and surgical findings can supplement.