Latest Staging and Treatment Approach for Endometrial Carcinoma
The most current staging system for endometrial carcinoma is the 2023 FIGO staging, which incorporates not only anatomical factors but also histological types, tumor patterns, and molecular classification to better reflect the complex nature of endometrial cancer and guide treatment decisions. 1
Current Staging Systems
2023 FIGO Staging (Most Recent)
The 2023 FIGO staging represents a significant evolution from traditional purely anatomical staging systems by incorporating:
- Histological tumor types (aggressive vs. non-aggressive)
- Lymphovascular space invasion (LVSI)
- Molecular classification (POLEmut, MMRd, NSMP, p53abn)
Key features of the 2023 staging include:
Stage I: Further subdivided based on invasion depth, histological type, and LVSI
- IA1: Non-aggressive histology limited to polyp or confined to endometrium
- IA2: Non-aggressive histology with <50% myometrial invasion with no/focal LVSI
- IA3: Low-grade endometrioid limited to uterus with simultaneous low-grade endometrioid ovarian involvement
- IB: Non-aggressive histology with ≥50% myometrial invasion with no/focal LVSI
- IC: Aggressive histology without myometrial invasion
Stage II: Incorporates cervical involvement and LVSI
- IIA: Non-aggressive histology infiltrating cervical stroma
- IIB: Non-aggressive histology with substantial LVSI
- IIC: Aggressive histology with any myometrial invasion
Stage III: Refined to better categorize extrauterine spread
- IIIA: Differentiates between adnexal vs. uterine serosa infiltration
- IIIB: Vaginal/parametrial infiltration and pelvic peritoneal metastasis
- IIIC: Refined lymph node metastasis categories
Stage IV: More detailed categorization of advanced disease
- IVA: Locally advanced disease infiltrating bladder or rectal mucosa
- IVB: Extrapelvic peritoneal metastasis
- IVC: Distant metastasis
Molecular classification is encouraged and denoted with "m" plus a subscript indicating the specific molecular subtype, which can result in upstaging or downstaging 1, 2.
2009 FIGO Staging (Previous System)
For reference, the 2009 FIGO staging system (which was used until recently) included:
Stage I: Tumor confined to corpus uteri
- IA: No or <50% myometrial invasion
- IB: Invasion ≥50% of myometrium
Stage II: Tumor invades cervical stroma but does not extend beyond uterus
Stage III: Local and/or regional spread
- IIIA: Tumor invades serosa and/or adnexae
- IIIB: Vaginal and/or parametrial involvement
- IIIC1: Positive pelvic lymph nodes
- IIIC2: Positive para-aortic lymph nodes
Stage IV: Tumor invades bladder/bowel mucosa or distant metastases
- IVA: Tumor invasion of bladder and/or bowel mucosa
- IVB: Distant metastases 3
Treatment Approach
Surgical Management
The cornerstone of treatment is surgical staging, which includes:
- Total hysterectomy and bilateral salpingo-oophorectomy [I, A]
- Peritoneal fluid collection/washings
- Thorough exploration of abdominal cavity and nodal areas 3
Lymphadenectomy considerations:
- Complete surgical staging recommended for intermediate-high risk endometrioid cancer (stage IA G3 and IB) [II, B]
- Sentinel lymph node mapping is increasingly used as an alternative to complete lymphadenectomy 3
- Minimally invasive approaches (laparoscopy, robotic surgery) show equivalent oncologic outcomes with fewer complications compared to laparotomy 3
Adjuvant Treatment Based on Risk Stratification
Low-risk (Stage IA, Grade 1-2, endometrioid histology):
- No adjuvant therapy required 3
Intermediate-risk:
- Vaginal brachytherapy is preferred over external beam radiation due to similar efficacy with better quality of life [I, A] 3
High-risk (Stage IB G3, non-endometrioid histology, or advanced stage):
- Pelvic radiotherapy recommended for locoregional control
- Platinum-based chemotherapy improves overall survival and progression-free survival compared to adjuvant radiotherapy alone [I, A] 3
- Consider combination of carboplatin and paclitaxel due to better toxicity profile [III, B] 3
Advanced/Metastatic Disease:
- Cytoreductive surgery when feasible
- Systemic therapy with platinum-based regimens
- Hormonal therapy for receptor-positive tumors [III, B] 3, 4
Important Considerations
- Preoperative evaluation should include transvaginal ultrasound, chest X-ray, and laboratory tests; MRI is best for assessing cervical involvement [I, A] 3
- Histopathological assessment is critical for determining tumor type, grade, depth of invasion, and LVSI
- Molecular classification is increasingly important for prognostication and treatment planning
- The role of sentinel lymph node biopsy continues to evolve as an alternative to complete lymphadenectomy 3
Pitfalls to Avoid
- Failing to recognize the importance of histological type and grade in treatment planning
- Underestimating the prognostic significance of LVSI
- Not considering molecular classification when available
- Performing unnecessary lymphadenectomy in low-risk patients
- Overtreatment of low-risk disease with adjuvant therapy
The integration of molecular and histological factors in the newest staging system reflects the growing understanding that endometrial cancer is not a single disease but rather a spectrum of malignancies with different biological behaviors and treatment responses.