Analysis of full coding sequence of the TP53 gene in invasive vulvar cancers: Implications for therapy

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.

Interobserver Agreement Across Subspecialties for Diagnosis of Differentiated Vulvar Intraepithelial Neoplasia and Predictive Values of 20 Histologic Features

CONTEXT.—

Differentiated vulvar intraepithelial neoplasia (dVIN) is a human papillomavirus-independent lesion with the potential for rapid progression to invasive squamous cell carcinoma (SCC). The histopathologic features of dVIN are diverse, have overlapping characteristics with lichen sclerosus (LS) and lichen simplex chronicus (LSC), and may be diagnosed by dermatopathologists or gynecologic pathologists because of the vulva's anatomic location.

OBJECTIVES.—

To identify the salient histopathologic features of dVIN, particularly those that predict progression to SCC, and to evaluate interobserver agreement in diagnosing dVIN within the same subspecialty and across subspecialties.

DESIGN.—

One general surgical pathologist, 2 pathology-trained dermatopathologists, and 1 gynecologic pathologist blinded to the final diagnoses were asked to record 20 histopathologic features and to provide their final interpretations on cases of dVIN (n = 65), LS (n = 126), LSC (n = 112), and LS with LSC (n = 6).

RESULTS.—

Interobserver agreement for the 4 diagnoses and 10 histopathologic features was moderate. Logistic regression analysis indicated that keratin pearls, basal pleomorphism, and basal layer disarray were independent variables for diagnosing dVIN (coefficients 1.95, 1.97, and 0.91, respectively; P < .001) and progression to SCC (coefficients 1.96, 1.20, and 1.08, respectively; P < .001).

CONCLUSIONS.—

There is no single histopathologic feature pathognomonic for dVIN; however, the presence of keratin pearls, basal pleomorphism, and basal layer disarray should raise high suspicion for dVIN and concurrent SCC. Expertise in both dermatologic and gynecologic pathology is beneficial for diagnosing dVIN.

Classification of Vulvar Squamous Cell Carcinoma and Precursor Lesions by p16 and p53 Immunohistochemistry: Considerations, Caveats, and an Algorithmic Approach

There is emerging evidence that vulvar squamous cell carcinoma (VSCC) can be prognostically subclassified into 3 groups based on human papillomavirus (HPV) and p53 status: HPV-associated (HPV+), HPV-independent/p53 wild-type (HPV-/p53wt), or HPV-independent/p53 abnormal (HPV-/p53abn). Our goal was to assess the feasibility of separating VSCC and its precursors into these 3 groups using p16 and p53 immunohistochemistry (IHC). A tissue microarray containing 225 VSCC, 43 usual vulvar intraepithelial neoplasia (uVIN/HSIL), 10 verruciform acanthotic vulvar intraepithelial neoplasia (vaVIN), and 34 differentiated VIN (dVIN), was stained for p16 and p53. Noncomplementary p16 and p53 patterns were resolved by repeating p53 IHC and HPV RNA in situ hybridization (ISH) on whole sections, and sequencing for TP53. Of 82 p16-positive VSCC, 73 (89%) had complementary p16 and p53 patterns and were classified into the HPV+ group, 4 (4.9%) had wild-type p53 staining, positive HPV ISH and were classified into the HPV+ group, whereas 5 (6.1%) had p53 abnormal IHC patterns (1 null, 4 overexpression), negativity for HPV ISH, and harbored TP53 mutations (1 splice site, 4 missense); they were classified as HPV-/p53abn. Of 143 p16-negative VSCC, 142 (99.3%) had complementary p53 and p16 patterns: 115 (80.4%) HPV-/p53abn and 27 (18.9%) HPV-/p53wt. One had a basal-sparing p53 pattern, positivity for HPV ISH and was negative for TP53 mutations-HPV+ category. The use of IHC also led to revised diagnoses-HSIL to dVIN (3/43), dVIN to vaVIN (8/34), and dVIN to HSIL (3/34). Overall, 215/225 VSCC (95.6%) could be easily classifiable into 3 groups with p16 and p53 IHC. We identified several caveats, with the major caveat being that "double-positive" p16/p53 should be classified as HPV-/p53abn. We propose an algorithm that will facilitate the application of p16 and p53 IHC to classify VSCC in pathology practice.

Precursors, pathways of carcinogenesis and molecular markers of vulvar squamous cell carcinoma. Literature review

The review analyzes and summarizes the results of the studies on the pathogenesis of  vulvar squamous cell carcinoma and its diagnostic features, reviews precursors and  molecular subtypes of carcinomas. Despite the relatively low incidence of this tumor, over the past few decades, there has been an upward trend in its incidence, including the incidence among young women. According to the latest World Health Organization classification of lower genital tumors from 2020, vulvar squamous cell carcinoma is divided into human papillomavirus (HPV) associated and HPV-independent. While these carcinomas are often morphologically similar, their mechanisms of carcinogenesis, precursors, and clinical outcomes are different. Just the detection of virus DNA in a tumor is not enough to establish HPV status. Meanwhile immunohistochemical detection of the expression of p16 and p53 proteins allows not only to separate two pathogenetic pathways of carcinogenesis, but also to identify its molecular subtypes. The data on the possible use of p16 and p53 expression as the disease prognosis molecular markers have been obtained. Currently, the tactics of treatment and monitoring patients does not depend on the HPV status of carcinoma; however, the results of recent studies suggest that women with HPV positive vulvar cancer have significantly higher survival rates and a lower risk of recurrence. Understanding the mechanisms of carcinogenesis and improving its diagnosis will advance the assessment of the individual risk of the progression of precancerous lesions, as well as the outcome and the occurrence of tumor recurrence. 

Six autoantibodies as potential differential biomarkers of hepatocellular carcinoma vs. liver cirrhosis and chronic hepatitis: A prospective multi‑institutional study

Serum autoantibodies respond not only to tumor-associated antigens of hepatocellular carcinoma (HCC) but also to those of liver cirrhosis (LC) and chronic hepatitis (CH). The present prospective multi-institutional study evaluated the diagnostic properties of six autoantibodies in distinguishing HCC from LC and CH. A total of 416 participants were enrolled: 149 With HCC, 76 with LC, 103 with CH and 88 healthy controls. Titers of serum autoantibodies to Sui1, RalA, p62, p53, c-myc and NY-ESO-1 were determined using enzyme-linked immunosorbent assays. All six antibodies were positive for HCC: s-Sui1-Abs (44%), s-RalA-Abs (23%), s-p62-Abs (21%), s-p53-Abs (13%), s-c-myc-Abs (11%) and s-NY-ESO-1-Abs (6%). The positivity rates of all six antibodies combined were 5% for healthy controls, 52% for CH, 58% for LC and 66% for HCC. The positivity rates of s-Sui1-Abs, s-RalA-Abs and s-p53-Abs were higher for HCC compared with those of LC and CH. However, the positivity rates of s-p62-Abs, s-c-myc-Abs and s-NY-ESO-1-Abs for HCC were not higher compared with those for LC and CH. Overall, autoantibodies were useful in differentiating patients with HCC from healthy individuals. However, they were not specific to HCC and were also present in the sera of individuals with CH and LC. These autoantibodies may be induced during the development of HCC. Clinical trial registration number: UMIN000014530 (date of registration 2011/07/11).

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

OBJECTIVES

We report the disease-specific survival of patients with human papillomavirus (HPV)-associated and HPV-independent vulvar squamous cell carcinomas and determine whether differences exist and are independent of stage and age at diagnosis.

METHODS

This was a retrospective cohort study with case note and pathology slide review of 265 consecutive women with vulvar squamous cell carcinoma. These patients were treated over a 15 year period (2001-2016) at a centralized cancer center covering half the population of New Zealand. The women's cancers were categorized dependent on their adjacent pathology, immunohistochemistry and HPV status following expert slide review. Disease-specific survival was calculated using Kaplan-Meier univariable and Cox proportional hazard (adjusting for stage, age, and HPV dependence) multivariable methods.

RESULTS

The survival analysis included 236 women with follow-up to 96 months; 124 of them were HPV-associated, 95 HPV-independent, and 17 were unclassifiable. Of the 236 women, 146 were stage 1 (92 HPV-associated, 49 HPV-independent, 5 unclassifiable), 13 stage II (7 HPV-associated, 6 HPV-independent), 62 stage III (20 HPV-associated, 34 HPV-independent, 8 unclassifiable) and 15 stage IV (5 HPV-associated, 6 HPV-independent, 4 unclassifiable). HPV-independent vulvar squamous cell carcinomas had significantly worse survival than HPV-associated vulvar squamous cell carcinomas independent of stage and age at diagnosis (HR 3.6 (95% confidence interval (CI): 1.6 to 8.2)). Tumors that were unclassifiable by HPV type also had significantly worse survival than HPV-associated tumors independent of stage and age at diagnosis (HR 6.2 (95% CI: 2.4 to 16.0)).

CONCLUSIONS

HPV-independent vulvar squamous cell carcinomas present more frequently in older women than HPV-associated tumors. However, the poorer prognosis is independent of age and stage, with worse outcomes even in early stage disease.

Squamous and Glandular Lesions of the Vulva and Vagina: What's New and What Remains Unanswered?

A number of changes have been introduced into the 5th Edition of the World Health Organization (WHO) Classification of squamous and glandular neoplasms of the vulva and vagina. This review highlights the major shifts in tumor classification, new entities that have been introduced, recommendations for p16 immunohistochemical testing, biomarker use, molecular findings and practical points for pathologists which will affect clinical care. It also touches upon several issues that still remain answered in these rare but undeniably important women's cancers.

The Vulvar Immunohistochemical Panel (VIP) Project: Molecular Profiles of Vulvar Squamous Cell Carcinoma

Simple Summary

This study investigated the immunohistochemical expression of 14 biological markers as potential prognostic/therapeutic factors in vulvar squamous cell carcinoma, comparing 53 node-negative (Group A) and 48 node-positive (Group B) patients. Our results show a significantly higher p16 expression (surrogate of HPV-related tumors) in the vulvar samples of non-metastatic patients. In Group B, PD-L1 positivity and high EGFR expression were found in the vast majority of vulvar and/or nodal specimens. VEGF showed strong/moderate-diffuse expression in almost 14% of all vulvar samples. A mutated p53 and over-expressed PD-L1 showed a significant association with nodal metastasis. Our results support a potential role of immune checkpoint inhibitors and anti-VEGF and anti-EGFR drugs, especially in patients with worse prognosis (metastatic, HPV-independent). A panel including EGFR, VEGF, PDL1, p16, and p53 might be performed routinely in primary tumor and repeated in case of lymph node metastases to identify changes in marker expression.

Abstract

Introduction: The study’s aim was to investigate the immunohistochemical (IHC) expression of biological markers as potential prognostic/therapeutic factors in vulvar squamous cell carcinoma (VSCC). Methodology: A series of 101 patients surgically treated at our center from 2016 to 2020 were retrospectively enrolled: 53 node-negative (Group A) and 48 node-positive (Group B). A total of 146 samples, 101 from primary tumor (T) and 45 from nodal metastases (N), were investigated. The IHC panel included: p16, p53, MLH1, MSH2, MSH6, PMS2, PD-L1, CD3, HER2/neu, ER, PR, EGFR, VEGF, and CD31. The reactions were evaluated on qualitative and semi-quantitative scales. Generalized Linear Model (GLM) and cluster analysis were performed in R statistical environment. A distance plot compared the IHC panel of T with the correspondent N. Results: In Group A: p16-positive expression (surrogate of HPV-dependent pathway) was significantly higher (20.8% vs. 6.2%, p = 0.04). In Group B: PD-L1 positivity and high EGFR expression were found, respectively, in 77.1% and 97.9% patients (T and/or N). Overall, p16-negative tumors showed a higher PD-L1 expression (60.9% vs. 50.0%). In both groups: tumoral immune infiltration (CD3 expression) was mainly moderate/intense (80% vs. 95%); VEGF showed strong/moderate-diffuse expression in 13.9% of T samples; CD31, related to tumoral microvessel density (MVD), showed no difference between groups; a mutated p53 and over-expressed PD-L1 showed significant association with nodal metastasis, with Odds Ratios (OR) of 4.26 (CI 95% = 1.14–15.87, p = 0.03) and 2.68 (CI 95% = 1.0–7.19, p < 0.05), respectively; since all mismatch repair proteins (MMR) showed a retained expression and ER, PR, and HER2/neu were negative, they were excluded from further analysis. The cluster analysis identified three and four sub-groups of molecular profiles, respectively, in Group A and B, with no difference in prognosis. The molecular signature of each N and corresponding T diverged significantly in 18/41 (43.9%) cases. Conclusions: Our results support a potential role of immune checkpoint inhibitors and anti-VEGF and anti-EGFR drugs especially in patients with worse prognosis (metastatic, HPV-independent). A panel including EGFR, VEGF, PDL1, p16, and p53 might be performed routinely in primary tumor and repeated in case of lymph node metastases to identify changes in marker expression.

Evaluation of Immunohistochemical Markers, CK17 and SOX2, as Adjuncts to p53 for the Diagnosis of Differentiated Vulvar Intraepithelial Neoplasia (dVIN)

Histological diagnosis of differentiated vulvar intraepithelial neoplasia (dVIN), the precursor of human papillomavirus (HPV)-independent vulvar squamous cell carcinoma (VSCC), can be challenging, as features of dVIN may mimic those of non-dysplastic dermatoses. To aid the diagnosis, p53-immunohistochemistry (IHC) is commonly used, and mutant expression patterns are used to support a histological diagnosis of dVIN. However, a proportion of dVIN can show wild-type p53-expression, which is characteristic of non-dysplastic dermatoses. Furthermore, recent research has identified a novel precursor of HPV-independent VSCC—the p53-wild-type differentiated exophytic vulvar intraepithelial lesion (de-VIL). Currently, there are no established diagnostic IHC-markers for p53-wild-type dVIN or de-VIL. We evaluated IHC-markers, cytokeratin 17 (CK17), and SRY-box 2 (SOX2), as diagnostic adjuncts for dVIN. For this, IHC-expression of CK17, SOX2, and p53 was studied in dVIN (n = 56), de-VIL (n = 8), and non-dysplastic vulvar tissues (n = 46). For CK17 and SOX2, the percentage of cells showing expression, and the intensity and distribution of expression were recorded. We also performed next generation targeted sequencing (NGTS) on a subset of dVIN (n = 8) and de-VIL (n = 8). With p53-IHC, 74% of dVIN showed mutant patterns and 26% showed wild-type expression. Median percentage of cells expressing CK17 or SOX2 was significantly higher in dVIN (p53-mutant or p53-wild-type) and de-VIL than in non-dysplastic tissues (p < 0.01). Diffuse, moderate-to-strong, full epithelial expression of CK17 or SOX2 was highly specific for dVIN and de-VIL. With NGTS, TP53 mutations were detected in both dVIN and de-VIL. We infer that immunohistochemical markers CK17 and SOX2, when used along with p53, may help support the histological diagnosis of dVIN.

Molecular characterization of invasive and in situ squamous neoplasia of the vulva and implications for morphologic diagnosis and outcome

Human papillomavirus (HPV)-independent vulvar squamous cell carcinoma (VSCC) is an aggressive clinical entity. Current diagnostic guidelines for premalignant lesions are ambiguous, and their molecular profile and progression events are still unclear. We selected 75 samples, from 40 patients, including 33 VSCC, 8 verrucous carcinomas (VC), 13 differentiated-type vulvar intraepithelial neoplasia (dVIN), 11 suspicious for dVIN (?dVIN), 6 differentiated exophytic vulvar intraepithelial lesions (DE-VIL), 2 vulvar acanthosis with altered differentiation (VAAD), and 2 usual-type vulvar intraepithelial neoplasia (uVIN/HSIL). Invasive and precursor lesions were matched in 29 cases. Clinical information, p16 immunohistochemistry, and mutation analysis were performed on all lesions. All dVIN, ?dVIN, DE-VIL, and VAAD were p16 negative, all uVIN/HSIL were p16 positive. In the HPV-independent group, mutations were identified in 6 genes: TP53 (n = 40), PIK3CA (n = 20), HRAS (n = 12), MET (n = 5), PTEN (n = 4), and BRAF (n = 1). TP53 mutations occurred in 73% (22/30) VSCC, 85% (11/13) dVIN, 70% (7/10) ?dVIN and no VC (0/8), DE-VIL (0/6) nor VAAD (0/2). Basal atypia was the only reliable feature of TP53 mutations. ?dVIN lesions that were non-acanthotic and atypical but obscured by inflammation, all harbored TP53 mutations. In lesions without TP53 mutations, PIK3CA (50% VC, 33% DE-VIL, 100% VAAD, 40% VSCC) and HRAS (63% VC, 33% DE-VIL, 0% VAAD, 20% VSCC) mutations were found. Mutational progression from in situ to invasive was seen (7/26, 27%) and usually involved TP53 (4/26, 15%). Cases with TP53 and PIK3CA co-mutations had the worse clinical outcomes (p < 0.001). We recommend testing for p53 in all HPV-independent lesions suspicious for dVIN, even in the presence of marked inflammation or non-acanthotic skin, particularly when close to a margin. VC, VAAD, and DE-VIL, were almost never mutated for TP53, but instead often harbored PIK3CA and HRAS mutations. In VSCC, combined TP53 and PIK3CA mutations may inform prognosis.

Diagnostic Criteria for Differentiated Vulvar Intraepithelial Neoplasia and Vulvar Aberrant Maturation

OBJECTIVE

The aim of the study was to describe the features required for diagnosis of differentiated vulvar intraepithelial neoplasia (dVIN) and vulvar aberrant maturation (VAM).

MATERIALS AND METHODS

The International Society of the Study of Vulvovaginal Diseases tasked the difficult pathologic diagnoses committee to develop consensus recommendations for clinicopathologic diagnosis of vulvar lichen planus, lichen sclerosus, and dVIN. The dVIN subgroup reviewed the literature and formulated diagnostic criteria that were reviewed by the committee and then approved by the International Society of the Study of Vulvovaginal Diseases membership.

RESULTS

Differentiated vulvar intraepithelial neoplasia is the immediate precursor of human papillomavirus (HPV)-independent vulvar squamous cell carcinoma and shows a spectrum of clinical and microscopic appearances, some overlapping with HPV-related neoplasia. The histopathologic definition of dVIN is basal atypia combined with negative or nonblock-positive p16 and basal overexpressed, aberrant negative, or wild-type p53. The most common pattern of dVIN is keratinizing with acanthosis, aberrant rete ridge pattern, and premature maturation. The morphologic spectrum of keratinizing dVIN includes hypertrophic, atrophic, acantholytic, and subtle forms. A few dVIN cases are nonkeratinizing, with basaloid cells replacing more than 60% of epithelium. Vulvar aberrant maturation is an umbrella term for lesions with aberrant maturation that arise out of lichenoid dermatitis and lack the basal atypia required for dVIN.

CONCLUSIONS

Evaluation of women at risk for dVIN and VAM requires a collaborative approach by clinicians and pathologists experienced in vulvar disorders. Close surveillance of women with lichen sclerosus and use of these recommendations may assist in prevention of HPV-independent squamous cell carcinoma through detection and treatment of dVIN and VAM.

Molecular events in the pathogenesis of vulvar squamous cell carcinoma

Vulvar squamous cell carcinomas (VSCC), which constitute over 90% of vulvar malignancies in adults, are classifiable into 2 subgroups that are mostly clinicopathologically distinct, a classification that is fundamentally based whether or not the tumors are HPV-mediated. In this review, we aim to summarize the recent advances in the understanding of molecular events in the pathogenesis of VSCC, including common and targetable mutations, copy number alterations, epigenetics, noncoding RNAs, and tumor immune microenvironment, which may provide insight into the future management of the disease. These events show substantial differences between the 2 subgroups, although significant areas of overlap exist. Recurrent, driver mutations appear to be substantially more prevalent in HPV(-) VSCC. TP53 mutations are the most common somatic mutations in VSCC overall, and are notably predominant in the HPV(-) VSCC, where 30-88% show a mutation. TP53 mutations are associated with worse patient outcomes, and co-mutations between TP53 and either HRAS, PIK3CA or CDKN2A appear to define subsets with even worse outcomes. A wide variety of other somatic mutations have been identified, including a subset with different mutational frequencies between HPV(+) and HPV(-) VSCC. CDKN2A mutations are common, and have been identified in 21 to 55% of HPV(-) VSCC, and in 2 to 25% of HPV(+) VSCC. Hypermethylation of CDKN2A is the most frequently reported epigenetic alteration in VSCC and the expression of some microRNAs may be associated with patient outcomes. The PTEN/PI3K/AKT/mTOR pathway is commonly altered in HPV(+) VSCC, and is accordingly potentially targetable. HPV-positivity/p16 block expression by immunohistochemistry has been found to be an independent prognostic marker for improved survival in VSCC, and may have some predictive value in VSCC patients treated with definitive radiotherapy. 22-39.3% and 68% of VSCC show EGFR amplification and protein overexpression respectively, although the prognostic and predictive value of an EGFR alteration requires additional study. Recurrent chromosomal gains in VSCCs have been found at 1q, 2q, 3q, 4p, 5p, 7p, 8p, 8q, and 12q, and there may be differential patterns of alterations depending on HPV-status. At least one-third of VSCC patients may potentially benefit from immune checkpoint inhibition therapy, based on a high frequency of PD-L1 expression or amplification, or a high tumor mutational burden. Additional studies are ultimately required to better understand the global landscape of genetic and epigenetic alterations in VSCC, and to identify and test potential targets for clinical application.

[Update on precursors of vulvar carcinoma]

Vulvar carcinomas represent 4% of all gynaecological cancers with 838 new cases in France in 2018. The precursor lesions of vulvar carcinomas are differentiated vulvar intraepithelial lesion (dVIN) in a context of lichen sclerosus and vulvar high-grade squamous intraepithelial lesion (HSIL) link to human papillomavirus (HPV) infection. Three typical clinical forms of HSIL are described: the Bowenoid papulosis, the Bowen's disease and the confluent VIN. Histopathology cannot differentiate effectively these two types of lesions. P16 and P53 immunostaining are valuable tools to respectively assess HPV infection and divide different types of dVIN. However, P53 immunostaining is still lacking sensibility to detect dVIN. First line therapies are medical treatment excluding the cases with a doubt of invasion. The gold standard treatment for dVIN and vulvar HSIL are respectively topical corticosteroids and imiquimod. Primary prevention for vulvar HSIL and dVIN are respectively HPV vaccination and early treatment of lichen sclerosus. Destructive therapy can be used in case of medical treatment failure such as CO2 laser, cryotherapy, dynamic phototherapy. Surgical indications should be carefully assessed between the risk of recurrence, the spread of the lesions, the aesthetic and functional aspect. Surgical procedures consist in either superficial vulvectomy or radical vulvectomy with or without flap reconstruction. Recurrence rate after surgery is around 20%.

Combined effect of recombinant human adenovirus p53 and curcumin in the treatment of liver cancer

The development of an effective therapeutic intervention for liver cancer is a worldwide challenge that remains to be adequately addressed. Of note, TP53, which encodes the p53 protein, is an important tumor suppressor gene, 61% of TP53 is functionally inactivated in liver cancer. Recombinant human adenovirus p53 (rAd-p53) is the first commercial product that has been used for gene therapy. In the present study, the combined mechanistic effects of rAd-p53 and curcumin, a naturally occurring compound with previously reported anti-inflammatory, antioxidant and anti-cancer properties, were assessed in liver cancer cells, using HepG2 cells as the model cell line. The administration of either curcumin or rAd-p53 promoted apoptosis, suppressed epithelial-mesenchymal transition (EMT) and blocked G2/M phase progression in HepG2 cells, which were potentiated further when both agents were applied together. Combined rAd-p53 and curcumin treatment resulted in higher p53 (P<0.01) and p21 (P<0.01) expression compared with rAd-p53 or curcumin were added alone, suggesting an additive effect on TP53 expression. Additionally, curcumin and rAd-p53 were demonstrated to regulate the activation of mitogen-activated protein kinases (MAPKs) ERK1/2, p38 MAPK and JNK. These results indicated that the combination of rAd-p53 with curcumin synergistically potentiates apoptosis and inhibit EMT compared with either rAd-p53 or curcumin treatment alone via the regulation of TP53 regulation. Mechanistically, this effect on TP53 expression may involve the ERK1/2, p38 MAPK and JNK signaling pathways. The current study provides new insights that can potentially advance the development of therapeutic strategies for liver cancer treatment.

Vulval squamous cell carcinoma and its precursors

Vulval squamous cell carcinoma (VSCC) can arise through two distinct pathways [human papillomavirus (HPV)-associated and HPV-independent], and these VSCC variants are recognised as different disease entities on the basis of different aetiologies, morphological features, molecular events during oncogenesis, precursor lesions, prognosis, and response to treatment. The precursor of HPV-associated VSCC, variously referred to as high-grade squamous intraepithelial lesion (HSIL) [vulvar intraepithelial neoplasia (VIN) 2/3] or usual-type VIN, is morphologically identical to the more common HSIL (cervical intraepithelial neoplasia 2/3) of the cervix. The precursor lesions of HPV-independent VSCC include differentiated VIN, differentiated exophytic vulvar intraepithelial lesion, and vulvar acanthosis with altered differentiation; these have been under-recognised by pathologists in the past, leading to delays in treatment. This review will discuss the recent advances in diagnostic surgical pathology of VSCC and its precursors, and how these diagnoses can impact on patient management.

Major p53 immunohistochemical patterns in in situ and invasive squamous cell carcinomas of the vulva and correlation with TP53 mutation status

The recent literature has shown that vulvar squamous cell carcinoma (VSCC) can be stratified into two prognostically relevant groups based on human papillomavirus (HPV) status. The prognostic value of p53 for further sub-stratification, particularly in the HPV-independent group, has not been agreed upon. This disagreement is likely due to tremendous variations in p53 immunohistochemical (IHC) interpretation. To address this problem, we sought to compare p53 IHC patterns with TP53 mutation status. We studied 61 VSCC (48 conventional VSCC, 2 VSCC with sarcomatoid features, and 11 verrucous carcinomas) and 42 in situ lesions (30 differentiated vulvar intraepithelial neoplasia [dVIN], 9 differentiated exophytic vulvar intraepithelial lesions [deVIL], and 3 high-grade squamous intraepithelial lesions or usual vulvar intraepithelial neoplasia [HSIL/uVIN]). IHC for p16 and p53, and sequencing of TP53 exons 4-9 were performed. HPV in situ hybridization (ISH) was performed in selected cases. We identified six major p53 IHC patterns, two wild-type patterns: (1) scattered, (2) mid-epithelial expression (with basal sparing), and four mutant patterns: (3) basal overexpression, (4) parabasal/diffuse overexpression, (5) absent, and (6) cytoplasmic expression. These IHC patterns were consistent with TP53 mutation status in 58/61 (95%) VSCC and 39/42 (93%) in situ lesions. Cases that exhibited strong scattered staining and those with a weak basal overexpression pattern could be easily confused. The mid-epithelial pattern was exclusively observed in p16-positive lesions; the basal and parabasal layers that had absent p53 staining, appeared to correlate with the cells that were positive for HPV-ISH. This study describes a pattern-based p53 IHC interpretation framework, which can be utilized as a surrogate marker for TP53 mutational status in both VSCC and vulvar in situ lesions.

Molecular pathways in vulvar squamous cell carcinoma: implications for target therapeutic strategies

BACKGROUND

Additional prognostic factors and personalized therapeutic alternatives for vulvar squamous cell carcinoma (VSCC), especially for advanced stages with poor prognosis, are urgently needed.

OBJECTIVES

To review and assess literature regarding underlying molecular mechanisms of VSCC target therapeutic and prognostic approaches.

METHODS

We performed a narrative literature review from the inception of the database up to January 2020 limited to English language, organizing knowledge in five main fields: extracellular and intracellular cell cycle deregulation, tumor immune microenvironment, tumor angiogenesis and hormones.

RESULTS

EGFR immunohistochemical overexpression/gene amplification, representing early events in VSCC carcinogenesis, have been correlated with a worse prognosis and led to inclusion of erlotinib in cancer guidelines. p16 expression and HPV positivity are linked to a better prognosis, while p53 overexpression is linked to a worse prognosis; thus, biomarkers could help tailoring conventional treatment and follow-up. The implications of PD-L1 positivity in reference to HPV status and prognosis are still not clear, even though pembrolizumab is part of available systemic therapies. The role of tumor angiogenesis emerges through data on microvessel density, immunohistochemical VEGF staining and evaluation of serum VEGF concentrations. Few data exist on hormonal receptor expression, even though hormonal therapy showed great manageability.

CONCLUSIONS

We suggest adding p16, p53 and HPV status to routine hystopathological examination of vulvar biopsies or surgical specimens. Predictive biomarkers for anti-EGFR and anti-PD-1/PD-L1 drugs are needed. Enough preclinical data supporting anti-angiogenic target therapies in clinical trials are existing. Hormonal receptor expression deserves further investigation.

The Clinical Relevance of p16 and p53 Status in Patients with Squamous Cell Carcinoma of the Vulva

Objective

To investigate the prognostic significance of HPV status in vulvar squamous cell carcinomas (VSCC) and to determine whether preoperative determination of p16 or p53 status would have clinical relevance.

Methods

Patients treated for VSCC at a tertiary hospital in Sydney, Australia, from 2002 to 2014, were retrospectively evaluated (n = 119). Histological specimens were stained for p53 and p16 expression, and HPV status was determined by PCR detection of HPV DNA.

Results

HPV DNA was detected in 19%, p16 expression in 53%, and p53 expression in 37% of patients. Kaplan-Meier survival estimates indicated that p16/HPV-positive patients had superior five-year disease-free survival (76% versus 42%, resp., p = 0.004) and disease-specific survival (DSS) (89% versus 75% resp., p = 0.05) than p53-positive patients. In univariate analysis, nodal metastases (p < 0.001), tumor size >4 cm (p = 0.03), and perineural invasion (p = 0.05) were associated with an increased risk of disease progression and p16 expression with a decreased risk (p = 0.03). In multivariable analysis, only nodal metastases remained independent for risk of disease progression (p = 0.01). For DSS, lymph node metastases (p < 0.001) and tumor size (p = 0.008) remained independently prognostic.

Conclusion

The p16/HPV and p53 status of VSCC allows separation of patients into two distinct clinicopathological groups, although 10% of patients fall into a third group which is HPV, p16, and p53 negative. p16 status was not independently prognostic in multivariable analysis. Treatment decisions should continue to be based on clinical indicators rather than p16 or p53 status.

Time series analysis of TP53 gene mutations in recurrent HPV-negative vulvar squamous cell carcinoma

The impact of TP53 gene mutations in recurrent HPV-negative vulvar squamous cell carcinomas is unclear. TP53 gene mutations were analyzed in archival tissues of 24 primary squamous cell carcinoma and local vulvar recurrences arising in chronic inflammatory dermatoses by analyzing the full coding sequence of the TP53 gene and correlated with disease-free survival. After resection of the primary squamous cell carcinoma with clear margins 19/24 patients had one and 5/24 had multiple recurrences. The first recurrence occurred after median of 46 months (range 12-180 months). In all, 17/24 (71%) primary squamous cell carcinomas had TP53 gene mutations and recurred after median disease-free intervals of 33 months (range 12-180). 14/17 (88%) recurrent squamous cell carcinomas carried again TP53 gene mutations, five with identical and nine with different, more complex TP53 gene mutations. 7/24 (29%) patients with a p53 wild-type primary SCC had the first recurrence after median 65 months (range 14-144) featuring p53 wild-type in 3/7 (43%) and TP53 gene mutations in 4/7 (57%) recurrent squamous cell carcinomas. Disease-free intervals of > 5 years (60-180 months) were observed in 10/24 patients total (42%; equally divided among p53 wild-type (5/7; 71%) and TP53 gene mutated (5/17; 29%) squamous cell carcinomas). In summary, squamous cell carcinomas recurred in the residual vulvar dermatosis independent of TP53 gene mutational status of the primary squamous cell carcinoma. The majority of TP53 gene mutated cancers recurred with different TP53 gene mutations, some of them more complex, and patients with p53 wild type developed TP53 gene mutations in the recurrent squamous cell carcinomas, possibly indicating increased genetic instability in longstanding chronic inflammatory dermatoses. A change of TP53 gene mutational status after > 5 years suggests de novo oncogenic events/carcinogenesis. Longer disease-free intervals in patients with p53 wild-type primary squamous cell carcinoma suggest that TP53 gene mutational status may serve as a prognostic marker for disease-free intervals.

Evaluation of CHK1 activation in vulvar squamous cell carcinoma and its potential as a therapeutic target in vitro

CHK1 is an important regulator of the cell cycle and DNA damage response, and its altered expression has been identified in various tumors. Chk1 inhibitors are currently being evaluated as monotherapy and as potentiators of chemotherapy in clinical settings. However, to our knowledge, no previous study has investigated either the activation status or the therapeutic potential of CHK1 targeting in vulvar cancer. Therefore, we examined the expression status of activated CHK1 forms pCHK1^Ser345, pCHK1^Ser317, pCHK1^Ser296, and pCHK1^Ser280 in 294 vulvar squamous cell carcinomas (VSCC) using immunohistochemistry and analyzed their relationships with various clinicopathological variables and clinical outcome. To aid translation of preclinical studies, we also assessed cell sensitivity to the Chk1 inhibition in two vulvar cancer cell lines. Compared to the levels of pCHK1^Ser345, pCHK1^Ser317, pCHK1^Ser296, and pCHK1^Ser280 in normal vulvar squamous epithelium, high nuclear pCHK1^Ser345 expression was found in 57% of vulvar carcinomas, whereas low nuclear pCHK1^Ser317, pCHK1^Ser296, and pCHK1^Ser280 expressions were observed in 58%, 64%, and 40% of the cases, respectively. Low levels of pCHK1^Ser317 and pCHK1^Ser280 in the nucleus correlated significantly with advanced tumor behaviors and aggressive features. None of pCHK1^Ser345, pCHK1^Ser317, pCHK1^Ser296, and pCHK1^Ser280 forms were identified as prognostic factors. In vitro inhibition of CHK1 by small molecular inhibitors or siRNA reduced viability by inducing DNA damage and apoptosis of vulvar cancer cell lines. In summary, we conclude that cellular functions regulated by CHK1 are phosphorylation/localization‐dependent and deregulation of CHK1 function occurs in VSCC and might contribute to tumorigenesis. Targeting CHK1 might represent as a useful antitumor strategy for the subgroup of VSCC harboring p53 mutations.

Genomic Characterization of Vulvar (Pre)cancers Identifies Distinct Molecular Subtypes with Prognostic Significance

Purpose: Vulvar cancer (VC) can be subclassified by human papillomavirus (HPV) status. HPV-negative VCs frequently harbor TP53 mutations; however, in-depth analysis of other potential molecular genetic alterations is lacking. We comprehensively assessed somatic mutations in a large series of vulvar (pre)cancers.Experimental Design: We performed targeted next-generation sequencing (17 genes), p53 immunohistochemistry and HPV testing on 36 VC and 82 precursors (sequencing cohort). Subsequently, the prognostic significance of the three subtypes identified in the sequencing cohort was assessed in a series of 236 VC patients (follow-up cohort).Results: Frequent recurrent mutations were identified in HPV-negative vulvar (pre)cancers in TP53 (42% and 68%), NOTCH1 (28% and 41%), and HRAS (20% and 31%). Mutation frequency in HPV-positive vulvar (pre)cancers was significantly lower (P = 0.001). Furthermore, a substantial subset of the HPV-negative precursors (35/60, 58.3%) and VC (10/29, 34.5%) were TP53 wild-type (wt), suggesting a third, not-previously described, molecular subtype. Clinical outcomes in the three different subtypes (HPV⁺, HPV^-/p53wt, HPV^-/p53abn) were evaluated in a follow-up cohort consisting of 236 VC patients. Local recurrence rate was 5.3% for HPV⁺, 16.3% for HPV^-/p53wt and 22.6% for HPV^-/p53abn tumors (P = 0.044). HPV positivity remained an independent prognostic factor for favorable outcome in the multivariable analysis (P = 0.020).Conclusions: HPV^- and HPV⁺ vulvar (pre)cancers display striking differences in somatic mutation patterns. HPV^-/p53wt VC appear to be a distinct clinicopathologic subgroup with frequent NOTCH1 mutations. HPV⁺ VC have a significantly lower local recurrence rate, independent of clinicopathological variables, opening opportunities for reducing overtreatment in VC. Clin Cancer Res; 23(22); 6781-9. ©2017 AACR.

Somatic Host Cell Alterations in HPV Carcinogenesis

High-risk human papilloma virus (HPV) infections cause cancers in different organ sites, most commonly cervical and head and neck cancers. While carcinogenesis is initiated by two viral oncoproteins, E6 and E7, increasing evidence shows the importance of specific somatic events in host cells for malignant transformation. HPV-driven cancers share characteristic somatic changes, including apolipoprotein B mRNA editing catalytic polypeptide-like (APOBEC)-driven mutations and genomic instability leading to copy number variations and large chromosomal rearrangements. HPV-associated cancers have recurrent somatic mutations in phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) and phosphatase and tensin homolog (PTEN), human leukocyte antigen A and B (HLA-A and HLA-B)-A/B, and the transforming growth factor beta (TGFβ) pathway, and rarely have mutations in the tumor protein p53 (TP53) and RB transcriptional corepressor 1 (RB1) tumor suppressor genes. There are some variations by tumor site, such as NOTCH1 mutations which are primarily found in head and neck cancers. Understanding the somatic events following HPV infection and persistence can aid the development of early detection biomarkers, particularly when mutations in precancers are characterized. Somatic mutations may also influence prognosis and treatment decisions.