HPV-independent and HPV-associated vulvar squamous cell carcinoma: two different cancers

Lymphovascular invasion and p16 expression are independent prognostic factors in stage I vulvar squamous cell carcinoma

The objective of this study was to identify clinicopathologic parameters associated with disease outcome in FIGO stage I vulvar squamous cell carcinoma (vSqCC). The cohort consisted of 126 patients diagnosed with vSqCC in the period 2006-2016 who underwent primary vulvar surgery and evaluation of groin lymph node status. Tumors were reviewed by an experienced gynecologic pathologist. p16 and p53 protein expression by immunohistochemistry and HPV status were analyzed in 116 tumors. Clinicopathologic parameters, protein expression and HPV status were analyzed for association with progression-free and overall survival (PFS, OS). p16 expression and aberrant p53 were found in 49 (42%) and 61 (53%) tumors, respectively. Sixty-six tumors were HPV-associated (57%). Relapse was diagnosed in 35/126 (28%) of patients, and 23 (18%) died of disease. Tumor diameter > 4 cm (p = 0.013), lymphovascular space invasion (LVSI; p < 0.001), the presence of lichen sclerosus (p = 0.019), p16 expression (p = 0.007), p53 expression (p = 0.012), HPV status (p = 0.021), lymph node metastasis (p < 0.001) and post-operative radiotherapy (p < 0.001) were significantly related to OS in univariate analysis. Tumor diameter > 4 cm (p = 0.038), LVSI (p = 0.003), the presence of lichen sclerosus (p = 0.004), p16 expression (p = 0.004), HPV status (p = 0.039), lymph node metastasis (p < 0.001) and post-operative treatment (p < 0.001), were significantly related to PFS in univariate analysis. Age, BMI and surgical resection involvement were not significantly associated with OS or PFS. In multivariate Cox analysis, LVSI and p16 expression were independent prognosticators of OS (p < 0.001 and p = 0.02, respectively) and PFS (p = 0.018, p = 0.037). In conclusion, LVSI and p16 expression are independent prognostic factors in stage I vSqCC.

Time trends in human papillomavirus prevalence and genotype distribution in vulvar carcinoma in Norway

INTRODUCTION

Approximately 25%-43% of all vulvar carcinomas are associated with human papillomavirus (HPV). In many countries, vulvar carcinoma incidence rates are increasing, possibly due to greater HPV exposure. However, studies exploring changes in HPV prevalence and genotype distribution in vulvar carcinoma over time are scarce. Our aim was to evaluate time trends in HPV prevalence and genotype distribution in vulvar squamous cell carcinoma in an unselected, nationwide sample of Norwegian women. Further, we explored clinical and histopathological aspects in relation to HPV status and investigated whether HPV status was associated with survival.

MATERIAL AND METHODS

All vulvar squamous cell carcinoma cases from 1970-1975 and 2000-2005 were extracted from the Cancer Registry of Norway and corresponding tissue blocks were retrieved. After detailed histology review, HPV testing was conducted using real-time TaqMan PCR. Overall survival rates were calculated using the Kaplan-Meier method. Multivariable Cox regression analysis was performed to estimate hazard ratios adjusted for age at diagnosis, stage and diagnostic period.

RESULTS

Histological review was performed on 352 vulvar squamous cell carcinoma cases. We were able to obtain valid HPV analysis results for 282 cases, Overall, 29.8% (95% CI 24.5%-35.5%) of cases were high-risk HPV (hrHPV)-positive. When comparing the two periods, we found that the percentage of hrHPV-positive tumors increased significantly from 23% (95% CI 16.0%-31.4%) in 1970-1975 to 35.3% (95% CI 27.8%-43.3%) in 2000-2005 (P = 0.025). The predominant genotypes were HPV 16 (73%), HPV 33 (21%), and HPV 18 (6%), with similar distributions in both periods. In the more recent cohort, several additional genotypes were detected: HPV 6, 11, 39, 45, 52, 58 and 66 were found in smaller percentages, ranging from 1.8% to 3.6%. In univariate analysis, patients with HPV-positive tumors showed improved overall survival compared with patients with HPV-negative tumors (hazard ratio [HR] 0.65, 95% CI 0.48-0.86).

CONCLUSIONS

The prevalence of HPV in vulvar squamous cell carcinomas in Norway was significantly higher in 2000-2005 than in 1970-1975. The three predominant genotypes were HPV 16, 33 and 18 in both time periods. However, several other HPV genotypes have emerged over the last decades. HPV-positivity was associated with better overall survival.

Updates in the Use of Immunohistochemical Stains in Breast and Gynecologic Pathology

CONTEXT.—

The use of immunohistochemical stains in breast and gynecologic pathology has become increasingly complex, with various diagnostic, prognostic, and predictive applications.

OBJECTIVE.—

To provide an update and review of immunohistochemical stains used in the practice of breast and gynecologic pathology. Established and new entities are reviewed, with descriptions of histomorphology and immunohistochemical staining patterns and discussion of interpretive pitfalls.

DATA SOURCES.—

Data were obtained from review of the English-language literature and firsthand experience of the authors in breast and gynecologic pathology.

CONCLUSIONS.—

Many entities in breast and gynecologic pathology benefit from evaluation with various immunohistochemical stains. These studies not only aid in the diagnosis and staging of tumors but also can provide prognostic and predictive information. Updated guidelines for recommended ancillary studies such as mismatch repair, p53, and human epidermal growth factor receptor 2 (HER2) studies in endometrium, as well as estrogen and progesterone receptors and HER2 in breast, are discussed. Finally, the use and interpretation of established and novel immunohistochemical stains are discussed in various breast and gynecologic malignancies.