Margins in vulvar cancer: challenges to classical clinicopathologic vulvar recurrence risk factors

Vulvar Cancer: Histopathologic Considerations and Nuances to Management

Vulvar cancer, although rare, poses significant challenges in diagnosis and treatment because of its histopathologic complexities and nuances. This paper reviewed key aspects of the management of vulvar cancer, focusing on histopathologic diagnosis, margin status interpretation, lymph node involvement assessment, and ongoing clinical trials.

Observational multicenter Italian study on vulvar cancer adjuvant radiotherapy (OLDLADY 1.2): a cooperation among AIRO Gyn, MITO and MaNGO groups

BACKGROUND

Adjuvant radiotherapy (aRT) has been shown to reduce the risk of local relapse in vulvar cancer (VC). In this multicentre study (OLDLADY-1.2), several Institutions have combined their retrospective data on VC patients to produce a real-world dataset aimed at collecting data on efficacy and safety of aRT.

METHODS

The primary study end-point was the 2-year-local control, secondary end-points were the 2-year-metastasis free-survival, the 2-year-overall survival and the rate and severity of acute and late toxicities. Participating centres were required to fill data sets including age, stage, tumor diameter, type of surgery, margin status, depth of invasion, histology, grading as well technical/dosimetric details of radiotherapy. Data about response, local and regional recurrence, acute and late toxicities, follow-up and outcome measures were also collected.

RESULTS

One hundred eighty-one patients with invasive VC from 9 Institutions were retrospectively identified. The majority of patients were stage III (63%), grade 2 (62.4%) squamous carcinoma (97.2%). Positive nodes were observed in 117 patients (64.6%), moreover tumor diameter > 4 cm, positive/close margins and depth of invasion deeper than 5 mm were found in 59.1%, 38.6%, 58% of patients, respectively. Sixty-one patients (33.7%) received adjuvant chemoradiation, and 120 (66.3%) received radiotherapy alone. aRT was started 3 months after surgery in 50.8% of patients. Prescribed volumes and doses heterogeneity was recorded according to margin status and nodal disease. Overall, 42.5% locoregional recurrences were recorded. With a median follow-up of 27 months (range 1-179), the 2-year actuarial local control rate, metastasis free and overall survival were 68.7%, 84.5%, and 67.5%, respectively. In term of safety, aRT leads to a prevalence of acute skin toxicity with a low incidence of severe toxicities.

CONCLUSIONS

In the context of aRT for VC the present study reports a broad spectrum of approaches which would deserve greater standardization in terms of doses, volumes and drugs used.

Postoperative management of vulvar cancer

The primary treatment for resectable vulvar cancer includes wide local excision of the primary tumor and surgical lymph node assessment. Following surgery, up to 40-50% of patients develop a local recurrence. Historically, the strongest predictor of local recurrence is a positive or close margin (defined as <8 mm), although recent studies question the importance of margin status. Post-operative radiotherapy to the vulva is recommended for all women with a positive margin where re-excision is not possible. Radiotherapy may also be considered in the setting of risk factors for local recurrence: close margin, lymphovascular invasion, large tumor size, and/or depth of invasion >5 mm. Nodal assessment is an important component of vulvar cancer management. A negative sentinel node is associated with a low false-negative predictive value (2% in patients with vulvar tumor <4 cm in GOG 173), 2-year groin recurrence rate of 2.3%, and 3-year disease-specific survival rate of 97% in patients with unifocal vulvar tumor <4 cm in the GROningen INternational Study on Sentinel nodes in Vulvar Cancer (GROINSS-V I) study. Thus, patients with tumor size <4 cm (without additional local risk factors) and negative sentinel node can be observed. Patients with sentinel node metastasis ≤2 mm can be treated with post-operative radiotherapy (2-year isolated groin recurrence rate of 1.6% in GROINSS-V II), as a safe alternative to lymphadenectomy. Patients with sentinel node metastasis >2 mm following sentinel node biopsy should undergo inguinofemoral lymphadenectomy followed by post-operative radiotherapy-based on the GROINSS-V II study, the 2-year isolated groin recurrence rate remains unacceptably high (22%) with radiotherapy alone. Retrospective studies suggest that the addition of concurrent chemotherapy to radiotherapy may improve survival. The ongoing GROINSS-V III study is investigating concurrent chemotherapy and radiotherapy dose escalation. The main goal of these post-operative treatments is to reduce the risk of local, and especially groin, recurrences, which are almost universally fatal.

An evaluation of prognostic factors, oncologic outcomes, and management for primary and recurrent squamous cell carcinoma of the vulva

OBJECTIVE

To evaluate prognostic factors, outcomes, and management patterns of patients treated for squamous cell carcinoma of the vulva.

METHODS

One hundred sixty-four women were retrospectively identified with primary squamous cell carcinoma of the vulva treated at our institution between 1/1996-12/2018. Descriptive statistics were performed on patient, tumor, and treatment characteristics. The χ² tests and t-tests were used to compare categorical variables and continuous variables, respectively. Recurrence free survival (RFS), overall survival (OS), and disease-specific survival (DSS) were analyzed with Kaplan-Meier estimates, the log-rank test, and Cox proportional hazards.

RESULTS

Median follow-up was 52.5 months. Five-year RFS was 67.9%, 60.0%, 42.1%, and 20.0% for stage I-IV, respectively. Five-year DSS was 86.2%, 81.6%, 65.0%, and 42.9% for stage I-IV, respectively. On multivariate analysis, positive margins predicted overall RFS (hazard ratio [HR]=3.55; 95% confidence interval [CI]=1.18-10.73; p=0.025), while presence of lichen sclerosus on pathology (HR=2.78; 95% CI=1.30-5.91; p=0.008) predicted local RFS. OS was predicted by nodal involvement (HR=2.51; 95% CI=1.02-6.13; p=0.043) and positive margins (HR=5.19; 95% CI=2.03-13.26; p=0.001). Adjuvant radiotherapy significantly improved RFS (p=0.016) and DSS (p=0.012) in node-positive patients. Median survival after treatment of local, groin, and pelvic/distant recurrence was 52, 8, and 5 months, respectively.

CONCLUSION

For primary treatment, more conservative surgical approaches can be considered with escalation of treatment in patients with concurrent precursor lesions, positive margins, and/or nodal involvement. Further studies are warranted to improve risk stratification in order to optimize treatment paradigms for vulvar cancer patients.