Interobserver reproducibility of the diagnosis of differentiated exophytic vulvar intraepithelial lesion (DEVIL) and the distinction from its mimics

Human Papilloma Virus-Independent/p53abnormal Keratinizing Squamous Cell Carcinoma of the Uterine Cervix Associated With Uterine Prolapse

Knowledge about the morphologic and molecular characteristics of cervical squamous cell carcinomas (CSCCs) associated with uterine prolapse is very limited. Detailed histopathological and immunohistochemical (p16, p53, and cytokeratin 17), as well as molecular evaluation for human papillomavirus (HPV)-DNA and p53-mutational analyses in 4 consecutive CSCCs associated with uterine prolapse with definition of a hitherto not well-described HPV-independent/p53abnormal precursor lesion (HPV-independent cervical intraepithelial neoplasia [CIN; differentiated CIN]) and molecular tumorigenetic pathway. Cases diagnosed within 7 years with a mean age of 75 (range: 69-83) years and a mean tumor size of 7.3 cm (range: 5.2-9.4 cm). All patients presented with locally advanced disease, and 1 woman died of the disease within 4, and another within 14 months of follow-up. All CSCCs and their adjacent precursor lesions were negative for p16, with aberrant p53-expression and diffuse and strong staining for cytokeratin 17. Both the CSCCs and their precursors were negative for HPV-DNA but harbored a TP53 mutation. The precursor lesions were characterized by epithelial thickening with superficial keratinization, and the presence of basal and parabasal keratinocytes with mitotic figures beyond the basal layer, thus showing features similar to those seen in differentiated types of vulvar intraepithelial lesions (vulvar intraepithelial neoplasia [VIN] syn. HPV-independent/p53abn VIN), suggesting the terminology of differentiated CIN or HPV-independent/p53abn CIN. An HPV-independent pathogenetic pathway with a p53-alteration was identified for these cases. CSCC associated with uterine prolapse represents HPV-independent tumors harboring a TP53 mutation. For the first time, a precursor lesion of HPV-independent CSCC of the uterine cervix is described with a differentiated VIN-like morphology, and a separate tumorigenic pathway defined.

Diagnosis of verruciform acanthotic vulvar intra-epithelial neoplasia (vaVIN) using CK17, SOX2 and GATA3 immunohistochemistry

AIMS

Verruciform acanthotic vulvar intra-epithelial neoplasia (vaVIN) is an HPV-independent, p53 wild-type lesion with distinct morphology and documented risk of recurrence and cancer progression. vaVIN is rare, and prospective distinction from non-neoplastic hyperplastic lesions can be difficult. CK17, SOX2 and GATA3 immunohistochemistry has emerging value in the diagnosis of HPV-independent lesions, particularly differentiated VIN. We aimed to test the combined value of these markers in the diagnosis of vaVIN versus its non-neoplastic differentials in the vulva.

METHODS AND RESULTS

CK17, SOX2 and GATA3 immunohistochemistry was evaluated on 16 vaVINs and 34 mimickers (verruciform xanthoma, lichen simplex chronicus, lichen sclerosus, psoriasis, pseudo-epitheliomatous hyperplasia). CK17 was scored as 3+ = full-thickness, 2+ = partial-thickness, 1+ = patchy, 0 = absent; SOX2 as 3+ = strong staining ≥ 10% cells, 2+ = moderate, 1 + =weak, 0 = staining in < 10% cells; and GATA3 as pattern 0 = loss in < 25% basal cells, 1 = loss in 25-75% basal cells, 2 = loss in > 75% basal cells. For analysis, results were recorded as positive (CK17 = 3+, SOX2 = 3+, GATA3 = patterns 1/2) or negative (CK17 = 2+/1+/0, SOX2 = 2+/1+/0, GATA3 = pattern 0). CK17, SOX2 and GATA3 positivity was documented in 81, 75 and 58% vaVINs, respectively, versus 32, 17 and 22% of non-neoplastic mimickers, respectively; ≥ 2 marker positivity conferred 83 sensitivity, 88 specificity and 86% accuracy in vaVIN diagnosis. Compared to vaVIN, SOX2 and GATA3 were differentially expressed in lichen sclerosus, lichen simplex chronicus and pseudo-epitheliomatous hyperplasia, whereas CK17 was differentially expressed in verruciform xanthoma and adjacent normal mucosa.

CONCLUSIONS

CK17, SOX2 and GATA3 can be useful in the diagnosis of vaVIN and its distinction from hyperplastic non-neoplastic vulvar lesions. Although CK17 has higher sensitivity, SOX2 and GATA3 are more specific, and the combination of all markers shows optimal diagnostic accuracy.

High-grade vulvar intraepithelial neoplasia: comprehensive characterization and long-term vulvar carcinoma risk

AIMS

Adequate diagnosis of human papillomavirus (HPV)-associated high-grade squamous intraepithelial lesion (HSIL) and HPV-independent vulvar intraepithelial neoplasia (VIN) is essential but can be challenging. We comprehensively characterized a large population-based series of vulvar lesions, originally reported as high-grade VIN, and assessed the cancer risk.

METHODS AND RESULTS

Baseline high-grade VIN of 751 patients were categorized by histopathological reassessment, integrating the results of immunohistochemistry (p16INK4a , p53, Ki-67) and HPV DNA testing. Integrated analyses resulted in 88.4% HPV-associated lesions (77.0% HSIL, 10.9% low-grade SIL [LSIL], and 0.4% vulvar squamous cell carcinoma [VSCC]), 10.9% HPV-independent lesions (6.1% HPV-independent VIN, 4.7% nondysplastic lesions, and 0.1% VSCC) and 1.1% inconclusive lesions. HSIL demonstrated p16INK4a block-positivity in 99.0%, increased Ki-67 in ≥2/3rd of the epithelium in 93.6%, and HPV positivity in 99.6%. In HSIL, a p53 wildtype mid-epithelial staining pattern was common (51.6%) while this was not observed in HPV-independent lesions. HPV-independent VIN harboured mutant p53 patterns in 65.2% and showed a wide morphological spectrum, ranging from differentiated to nondifferentiated ('HPV-associated-like', in 41.3%). Kaplan-Meier analyses showed a 10-year cancer risk of 8.0% in HPV-associated HSIL, 67.4% in HPV-independent VIN/p53mutant, and 27.8% in HPV-independent VIN/p53wildtype. Strikingly, the 10-year cancer risk was 73.3% in HPV-independent VIN with nondifferentiated ('HPV-associated-like') morphology.

CONCLUSION

Immunohistochemistry by p16INK4a and p53 is highly recommended for optimal categorization into HPV-associated and HPV-independent VIN, which is of utmost importance given the different cancer risk. The high cancer risk of HPV-independent VIN underscores the need for surgical treatment and close follow-up, especially in case of a p53 mutant pattern and/or nondifferentiated morphology.

Vulvar biopsy: Punch biopsy or cervical forceps biopsy?

OBJECTIVES

The primary objective of our study is to investigate the rate of non-contributory biopsies between punch biopsy(PB) and cervical forceps biopsy(CFB) for a vulvar lesion seen in consultation. The secondary objective of our study is to evaluate the rate of underestimation of a more severe lesion for patients who have undergone vulvar excision.

MATERIAL AND METHOD

This is a retrospective, descriptive, and comparative study conducted at three centers. The study population consisted of patients who underwent vulvar biopsy between 2017 and 2022 in a gynecological surgery consultation at two French hospitals, as well as a city office. The biopsy techniques used were punch or cervical forceps biopsy. Quantitative variables were analyzed using the Mann-Whitney test, while Pearson's or Fisher's Xi2 tests were used for qualitative variables. The significance level was set at 5%.

RESULTS

We conducted a retrospective study of 179 vulvar biopsies, of which 100 were punch biopsies and 79 were cervical forceps biopsies, from a total of 107 patients. There was no significant difference in the rate of non-contributory biopsies between the PB and CB groups (p = 1). When analyzing the secondary endpoint of our study, which included 68 patients who underwent vulvectomy after vulvar biopsy, we found that 66 patients (97%) had a good correlation between the pathology of the vulvar biopsy and that of the vulvectomy specimen.

CONCLUSION

Vulvar biopsy techniques using punch or cervical forceps appear to have similar diagnostic performance and are associated with comparable and low rates of underestimation of invasive lesions.

p53-Abnormal "Fields of Dysplasia" in Human Papillomavirus-Independent Vulvar Squamous Cell Carcinoma Impacts Margins and Recurrence Risk

Abnormal p53 (p53abn) immunohistochemical (IHC) staining patterns can be found in vulvar squamous cell carcinoma (VSCC) and differentiated vulvar intraepithelial neoplasia (dVIN). They can also be found in the adjacent skin that shows morphology that falls short of the traditional diagnostic threshold for dVIN. Vulvectomy specimens containing human papillomavirus-independent p53abn VSCC with margins originally reported as negative for invasive and in situ disease were identified. Sections showing the closest approach by invasive or in situ neoplasia to margins were stained with p53 IHC stains. We evaluated the following: (1) detection of morphologically occult p53abn in situ neoplasia, (2) rates of margin status change after p53 IHC staining, and (3) effect of p53abn IHC staining at margins on the 2-year local recurrence rates. Seventy-three human papillomavirus-independent p53abn VSCCs were included. Half (35/73, 48%) had documented an in situ lesion in the original report. The use of p53 IHC staining identified 21 additional cases (29%) with the p53abn in situ lesions that were originally unrecognized. The histology of in situ lesions in the p53abn "field" varied and became more subtle (morphologically occult) farther away from the VSCC. Fifteen (21%) cases had a morphologically occult and previously unrecognized p53abn in situ lesion present at a resection margin, which conferred an increased risk of local recurrence (5/7 [71.4%] vs 6/22 [27.3%], P = .036). The p53abn in situ lesions at a margin were confirmed to have TP53 mutations by sequencing. p53 IHC staining identified morphologically occult p53abn in situ lesions surrounding human papillomavirus-independent VSCC. p53abn IHC staining at a margin was associated with a 3-fold increased risk of local recurrence.

HPV-independent, p53-wild-type vulvar intraepithelial neoplasia: a review of nomenclature and the journey to characterize verruciform and acanthotic precursor lesions of the vulva

Vulvar squamous cell carcinomas and their precursors are currently classified by the World Health Organization based on their association with high-risk human papillomavirus (HPV). HPV independent lesions often harbor driver alterations in TP53, usually seen in the setting of chronic vulvar inflammation. However, a group of pre-invasive vulvar squamous lesions is independent from both HPV and mutant TP53. The lesions described within this category feature marked acanthosis, verruciform growth and altered squamous maturation, and over the last two decades several studies have added to their characterization. They have a documented association with verrucous carcinoma and conventional squamous cell carcinoma of the vulva, suggesting a precursor role. They also harbor recurrent genomic alterations in several oncogenes, mainly PIK3CA and HRAS, indicating a neoplastic nature. In this review, we provide a historical perspective and a comprehensive description of these lesions. We also offer an appraisal of the terminology used over the years, going from Vulvar Acanthosis with Altered Differentiation and Verruciform Lichen Simplex Chronicus to Differentiated Exophytic Vulvar Intraepithelial Lesion and Vulvar Aberrant Maturation, the latter term having been recently proposed by the International Society for the Study of Vulvovaginal Diseases. In line with the recognition of these lesions by the 2020 World Health Organization Classification of Tumours as a neoplastic precursor, we herein propose the term HPV-independent, p53-wild-type verruciform acanthotic Vulvar Intraepithelial Neoplasia (HPVi(p53wt) vaVIN), which better conveys not only the pathology but also the neoplastic nature and the biologic risk inherent to these uncommon and challenging lesions. We outline strict morphologic and immunohistochemical criteria for its diagnosis and distinction from mimickers. Immunohistochemistry for p16 and p53 should be performed routinely in the diagnostic work-up of these lesions, and the morphologic alternative term vaVIN should be reserved for instances in which p16/HPV/p53 status is unknown. We also discuss management considerations and the need to further explore precursors within and beyond the spectrum of verruciform acanthotic vulvar intraepithelial neoplasia.

Differentiated Exophytic Vulvar Intraepithelial Lesions: Case Reports and Review of Literature

OBJECTIVES

The aims of this article were to describe 2 patients with a pathological diagnosis of differentiated exophytic vulvar intraepithelial lesion and to summarize the literature regarding this relatively new diagnosis.

MATERIALS AND METHODS

The existing literature was searched on December 1, 2021, using the MEDLINE database (1966-2021), and all combinations of the following search terms were used: "differentiated exophytic vulvar intraepithelial lesion" and "differentiated vulvar intraepithelial neoplasia."

RESULTS

Patients were postmenopausal and reported persistent vulvar itch associated with white hypertrophic plaques. Initial biopsies did not identify differentiated exophytic vulvar intraepithelial lesion. Invasive squamous cell carcinoma was found in both cases after surgical excision.

CONCLUSIONS

Differentiated vulvar intraepithelial lesions and invasive squamous cell carcinoma should be considered in the differential diagnosis of vulvar itch associated with hypertrophic plaques in postmenopausal women. Excision of suspicious plaques is recommended for definitive diagnosis.

Key changes to the world health organisation (who) classification of female genital tumours introduced in the 5TH edition (2020)

An updated World Health Organisation (WHO) Classification of Female Genital Tumours was published in Autumn 2020. We discuss the major new additions and changes from the prior 2014 Classification with discussion of the reasons underlying these. A feature of the new Classification is the greater emphasis on key molecular events with integration of morphological and-molecular features. Most of the major changes from the prior Classification pertain to uterine (corpus and cervix) and vulval tumours but changes in all organs are covered.