A review of prognostic factors in squamous cell carcinoma of the vulva: Evidence from the last decade

Effect of known pathological risk factors on the incidence of metastatic lymph nodes and survival in early-stage vulvar cancer: SEER analysis

OBJECTIVE

The current study was performed to evaluate the incidence of positive lymph nodes (LNs) in relation to known pathological risk factors, specifically among patients with apparent low-grade, small tumors.

METHODS

We used the Surveillance, Epidemiology, and End Results (SEER) database to retrospectively identify patients with vulvar squamous cell carcinoma (SCC) diagnosed between January 1, 2000, and December 31, 2019, with known tumor size and regional LN examined. A comparison between patients who had positive and negative LNs was conducted to identify risk factors for LN metastases in relation to survival. Subgroup analysis was conducted in patients with diagnosed grade 1 vulvar SCC and tumor size up to 2 cm according to the status of LNs.

RESULTS

Multivariate analysis found that both grade of disease and tumor size were significant factors in predicting LN status. Among patients with low-grade small tumors up to 2 cm, the odds ratio for positive LNs was 2.5 for those with tumor size larger than 1 cm. In a multivariate survival analysis, older age, larger tumor size, and positive LNs were independently associated with decreased survival.

CONCLUSIONS

The current study confirms that among small tumors, those larger than 1 cm have a significantly increased risk for positive nodes compared with those smaller than 1 cm, and, among this specific group, patients with positive nodes have decreased survival. Future studies are needed to answer the question of whether, in the era of the sentinel node procedure, it is safe to omit LN evaluation altogether.

Prognostic nomograms to predict overall survival and cause specific death in vulvar squamous cell carcinoma

Objective

The incidence of vulvar squamous cell carcinoma has been rising in recent decades. The prognosis of patients with vulvar squamous cell carcinoma was explored, and nomograms were constructed to predict survival rates.

Methods

Vulvar squamous cell carcinoma patient data were downloaded from the Surveillance, Epidemiology, and End Results (SEER) database and randomly divided into a training dataset and testing dataset. Univariable and multivariable Cox regression were used to identify risk factors affecting vulvar squamous cell carcinoma overall survival in the training dataset. Cumulative incidence function and Fine–Gray regression were used to analyze cancer specific death in the training dataset. Overall survival and cancer specific death nomograms were constructed and validated in the testing and whole datasets. Receiver operating characteristic and calibration were used to verify the predictive value and clinical applicability of the models.

Results

Age ≥60 years, grade 3, American Joint Committee on Cancer stages III and IV, TNM (tumor, nodes, metastasis) stages T2, T3, N1, and M1 had a negative effect on overall survival in vulvar cancer patients. Surgery (hazard ratio (HR)=0.416, 95% confidence interval (CI) 0.349 to 0.496, p<0.001) and chemotherapy (HR=0.637, 95% CI 0.544 to 0.746, p<0.001) may improve overall survival. Age, tumor grade, American Joint Committee on Cancer stage, T stage, N stage, M stage, surgery, and chemotherapy significantly affected vulvar cancer specific death. For area under the receiver operating characteristic curve, the predictive ability of the nomograms for overall survival and cancer specific death for 1 year (area under the curve (AUC)=0.862), 3 years (AUC=0.832), and 5 years (AUC=0.808) were all >0.800.

Conclusion

The nomograms established in our study had an excellent predictive ability for overall survival and cancer specific death in vulvar cancer patients.

Integrin αvβ6 as a Target for Tumor-Specific Imaging of Vulvar Squamous Cell Carcinoma and Adjacent Premalignant Lesions

Surgical removal of vulvar squamous cell carcinoma (VSCC) is associated with significant morbidity and high recurrence rates. This is at least partially related to the limited visual ability to distinguish (pre)malignant from normal vulvar tissue. Illumination of neoplastic tissue based on fluorescent tracers, known as fluorescence-guided surgery (FGS), could help resect involved tissue and decrease ancillary mutilation. To evaluate potential targets for FGS in VSCC, immunohistochemistry was performed on paraffin-embedded premalignant (high grade squamous intraepithelial lesion and differentiated vulvar intraepithelial neoplasia) and VSCC (human papillomavirus (HPV)-dependent and -independent) tissue sections with healthy vulvar skin as controls. Sections were stained for integrin αvβ6, CAIX, CD44v6, EGFR, EpCAM, FRα, MRP1, MUC1 and uPAR. The expression of each marker was quantified using digital image analysis. H-scores were calculated and percentages positive cells, expression pattern, and biomarker localization were assessed. In addition, tumor-to-background ratios were established, which were highest for (pre)malignant vulvar tissues stained for integrin αvβ6. In conclusion, integrin αvβ6 allowed for the most robust discrimination of VSCCs and adjacent premalignant lesions compared to surrounding healthy tissue in immunohistochemically stained tissue sections. The use of an αvβ6 targeted near-infrared fluorescent probe for FGS of vulvar (pre)malignancies should be evaluated in future studies.

Lichen Sclerosis is Associated With a High Rate of Local Failure After Radio(chemo)therapy for Vulvar Cancer

AIMS

Radio(chemo)therapy plays an important role in the treatment of vulvar cancer, either as postoperative treatment or as definitive treatment in patients who present with inoperable disease. Only limited data are available regarding outcome after modern state of the art radio(chemo)therapy and more information regarding prognostic factors are warranted. The aim of this study was to evaluate disease outcomes after radio(chemo)therapy in patients with vulvar cancer with special emphasis on the impact of lichen sclerosis on local control.

MATERIALS AND METHODS

All consecutive patients (n = 109) from the western half of Denmark who were treated with definitive (n = 52) or postoperative (n = 57) radio(chemo)therapy between January 2013 and January 2020 were included. Local control, cause-specific survival and overall survival, as well as morbidity, were analysed using Kaplan-Meier statistics. Prognostic factors for local control were analysed in univariate and multivariate analysis.

RESULTS

At a median follow-up of 35 (4-95) months, 46 (42.0%) patients were diagnosed with recurrence. Eighty per cent of the recurrences were located to the vulva region, leading to a 5-year local control of 58.9% (confidence interval 47.9-69.9). Cause-specific survival was 62.9% (confidence interval 53.1-72.7), whereas overall survival was 58.0% (confidence interval 47.6-68.5). Grade 3-4 morbidity was diagnosed in 10 (9%) patients. Lichen sclerosis (hazard ratio 3.89; confidence interval 1.93-7.79) was an independent risk factors for local recurrence. Patients without lichen sclerosis had a 5-year local control rate of 83.6% (confidence interval 67.2-99.0) and 62.6% (confidence interval 43.2-82.0) after postoperative and definitive radio(chemo)therapy, respectively. In patients with lichen sclerosis, the local control rate was 44.0% (confidence interval 19.3-69.0) and 17.6% (confidence interval 0-30.0) after postoperative and definitive radio(chemo)therapy, respectively.

CONCLUSION

Radio(chemo)therapy plays an important role in the treatment of vulvar cancer. However, despite dose escalation, a substantial proportion of patients experienced local relapse. Pre-existing lichen sclerosis seems to have a significant impact on the risk of recurrence. This should influence surveillance programmes for these patients.