Álvaro P. Pinto

Differentiated vulvar intraepithelial neoplasia contains Tp53 mutations and is genetically linked to vulvar squamous cell carcinoma

Differentiated vulvar intraepithelial neoplasia is a unique precursor to vulvar squamous cell carcinoma that is typically HPV-negative and frequently associated with nuclear p53 staining. These features imply a mode of pathogenesis involving somatic mutations. However, the genetic relationship of differentiated vulvar intraepithelial neoplasm and vulvar squamous cell carcinoma and the role of Tp53 mutations in this process have not been resolved. We analyzed 11 differentiated vulvar intraepithelial neoplasms and 6 associated vulvar squamous cell carcinomas. Sections were stained for p53 and p63 and DNA from multiple epithelial sites, representing normal control tissues (n=10), differentiated vulvar intraepithelial neoplasias (n=18), and vulvar squamous cell carcinomas (n=6), were obtained by laser capture microdissection, and sequenced for exons 2–11 of Tp53. Six of 10 cases contained at least one Tp53 mutation-positive differentiated vulvar intraepithelial neoplasia focus; 4 strongly p53 immuno-positive and 2 negative. Staining for p53 and p63 co-localized, targeting the immature epithelium, but surface epithelium was Tp53 mutation-positive. Four of five vulvar squamous cell carcinomas were Tp53 mutation-positive; two shared identical Tp53 mutation with adjacent differentiated vulvar intraepithelial neoplasia. Disparate foci of differentiated vulvar intraepithelial neoplasia often showed different mutations consistent with multiple neoplastic clones. Differentiated vulvar intraepithelial neoplasia is, with few exceptions, associated with Tp53 mutations and will be p53 immunopositive when missense mutations (versus some nonsense and all deletion mutations) are present. Multiple Tp53 mutations in different sites supports the presence of multiple independent genetic events, but shared Tp53 mutations in both differentiated vulvar intraepithelial neoplasia and vulvar squamous cell carcinoma support a genetic relationship between the two. The confinement of p53 staining to immature cell nuclei is consistent with maturation-dependent degradation of mutant p53 protein.

Frequent Loss of Heterozygosity for Chromosome 10 in Uterine Leiomyosarcoma in Contrast to Leiomyoma

Distinction of malignant uterine leiomyosarcomas from benign leiomyomas by morphological criteria is not always possible. Leiomyosarcomas typically have complex cytogenetic abnormalities; in contrast, leiomyomas have simple or no cytogenetic abnormalities. To understand better the biological distinction(s) between these tumors, we analyzed two other potential markers of genomic instability, loss of heterozygosity (LOH) and microsatellite instability. We examined archival materials from 16 leiomyosarcomas and 13 benign leiomyomas by polymerase chain reaction for 26 microsatellite polymorphisms. Markers were selected based on previous reports of cytogenetic or molecular genetic abnormalities in leiomyosarcomas or leiomyomas and surveyed chromosomes 7, 9, 10, 11, 12, 14, 15, 16, 18, 21, and X. LOH for markers on chromosomes 15, 18, 21, and X was infrequent in leiomyosarcomas (1 of 6 tumors for each chromosome) and not observed for markers on chromosomes 7, 9, 11, 12, 14, or 16. Interestingly, 8 of 14 (57.2%) informative leiomyosarcomas had LOH for at least one marker on chromosome 10 and involved both chromosomal arms in 45.5% (5 of 11). In contrast to leiomyosarcomas, LOH for chromosome 10 was not found in 13 benign leiomyomas. Microsatellite instability was found infrequently in leiomyosarcomas and not detected in leiomyoma. Clinicopathological features (eg, atypia, necrosis, and clinical outcome) did not appear to correlate with LOH for chromosome 10. In contrast to other chromosomes studied, LOH on chromosome 10 was frequent in leiomyosarcomas and absent in benign leiomyomas.

Co-fatores do HPV na oncogênese cervical

Human papillomavirus (HPV) plays a central rule in uterine cervix carcinogenesis. Other factors direct or indirectly influence the installation of this mechanism in cervical squamous epithelium. Investigations regarding mechanisms of interaction of these factors with viral elements are found in the literature of the last 20 years. The present review article discusses possible co-factors of HPV in the genesis of the squamous carcinoma of uterine cervix, taking into account only the factors whose association with the virus or cervical cancer has been documented by experimental studies, and not based just on clinical or epidemiological data. Among the approached parameters are immunological factors (local and humoral immune response), the association with Acquired Immune Deficiency Syndrome, genetic factors as protein p53 polymorphism, tabagism and the use of oral contraceptives. All these factors interact in variable intensity with oncoproteins and other HPV elements, increasing and facilitating the virus action in host cells, leading to the development of immortalization and carcinogenesis.

Allelic loss in human papillomavirus-positive and -negative vulvar squamous cell carcinomas

Vulvar squamous cell carcinoma (VSCC) is a biologically and morphologically diverse disease, consisting of human papillomavirus (HPV)-positive and -negative tumors that differ in their morphological phenotypes and associated vulvar mucosal disorders. This study analyzed the frequencies of allelic loss (loss of heterozygosity (LOH)) in HPV-positive and -negative VSCCs to identify potential targets for the study of preinvasive diseases, to determine whether HPV status influenced patterns of LOH, and to determine whether these patterns differed from HPV-positive tumors of another genital site, cervical squamous cell carcinomas (CSCC). DNA extracted from microdissected archival sections of two index tumors, one each HPV negative and positive, was analyzed for LOH at 65 chromosomal loci. Loci scoring positive with either sample were included in an analysis of 14 additional cases that were also typed for HPV. Frequencies of LOH at loci were computed in a panel of HPV-positive and -negative VSCCs. Twenty-nine loci demonstrated LOH on the initial screen and were used to screen the remaining 14 tumors. High frequencies of LOH were identified, some of which were similar to a prior karyotypic study (3p, 5q, 8p, 10q, 15q, 18q, and 22q) and others of which had not previously been described in VSCC (1q, 2q, 8q, 10p, 11p, 11q, 17p, and 21q). With the exception of 5q and 10p, there were no significant associations between frequency of LOH and HPV status in VSCC. LOH at 3p and 11q were frequent in both VSCC and CSCC; however, allelic losses at several sites, including 5q, 8q, 17p, 21q, and 22q, were much more common in VSCC. VSCCs exhibit a broad range of allelic losses irrespective of HPV status, with high frequencies of LOH on certain chromosomal arms. This suggests that despite their differences in pathogenesis, both HPV-positive and -negative VSCCs share similarities in type and range of genetic losses during their evolution. Whether the different frequencies of LOH observed between VSCC and CSCC are real or reflect differences in stage and/or tumor size remains to be determined by further comparisons. The role of these altered genetic loci in the genesis of preinvasive vulvar mucosal lesions merits additional study.

Relationship of margin status and radiation dose to recurrence in post-operative vulvar carcinoma

OBJECTIVE To evaluate the effect of margin status and radiation dose in patients treated with radiation therapy (RT) for vulvar cancer. Clinical outcomes included vulvar recurrence (VR), relapse-free survival (RFS) and overall survival (OS). METHODS We retrospectively reviewed the records of 300 patients with Stage I-IVA vulvar cancer treated between 1988 and 2009. Slides were reviewed and margin status was scored as negative (≥ 1 cm), close (<1cm) or positive after formalin fixation. Cox proportional hazards models were constructed to determine significant prognostic factors for vulvar relapse. RESULTS Of 205 eligible patients, 69 (34%) had negative surgical margins, 116 (56%) had close margins and 20 (10%) had positive margins. Median follow-up time was 49 months. The 4-year RFS rate was 53% and OS was 73%. Of 78 recurrences, 62 had the vulva as the first site of recurrence. The 4-year rates of freedom from vulvar recurrence were 82%, 63% and 37% for those with negative, close and positive margins, respectively (p for trend=0.005). On multivariate analysis, close margins (HR=3.03, 95% CI 1.46-6.26) and positive margins (HR=7.02, 95% CI 2.66-18.54) were associated with a significantly increased risk of vulvar relapse. Those who received a dose ≥ 56 Gy had a lower risk of relapse than those who received ≤ 50.4 Gy (p<0.05). Though recurrences were noted with margins up to 9 mm, the highest risk of vulvar recurrence was associated with margins ≤ 5 mm (p=0.002). CONCLUSIONS Close or positive margins were associated with a significantly increased risk of vulvar recurrence. Radiation with a dose ≥ 56 Gy may decrease the risk of vulvar recurrence.

Immunomarkers in Gynecologic Cytology: The Search for the Ideal ‘Biomolecular Papanicolaou Test’

Harnessing the knowledge we have gained on the cell cycle disruption caused by human papillomaviruses (HPV) will likely lead to improved screening modalities for cervical cancer and its precursors. An easily applied biomarker that has high specificity and sensitivity would represent an attractive alternative or complement to cytology and HPV testing. To date, a number of promising markers have been investigated. These include p16INK4A, MIB-1, BD-ProEx C, and L1. Newer possibilities involve a variety of gene products associated with aberrations of chromosome 3q, such as telomerase, p63, and PIK3CA, as well the combination of biomarkers such as p16INK4A and MIB-1 in the same assay. Although none of them has yet been incorporated into screening algorithms or found its way into routine practice, their performance characteristics remain a focus of current investigations. This review summarizes what we know and where we hope to go in translating basic pathobiology into clinical practice.

Phosphorylated S6 as an immunohistochemical biomarker of vulvar intraepithelial neoplasia

As life expectancy lengthens, cases of non-viral-associated vulvar squamous cell carcinoma and its precursor lesion, so-called differentiated vulvar intraepithelial neoplasia (VIN), continue to increase in frequency. Differentiated VIN often is difficult to recognize and failure to detect it before invasion results in morbidity and mortality. Thus, identification of a reliable biomarker for this type of lesion would be of great clinical benefit. Our recent studies have identified activation (ser235/236 phosphorylation) of ribosomal protein S6 (p-S6) in basal epithelial cells as an event that precedes and accompanies laminin γ2 overexpression in most preinvasive oral dysplasias. To test this as a potential biomarker of vulvar dysplasia, we immunostained seven differentiated VINs and nine papillomavirus-related ‘classic’ VINs, most of which were associated with carcinoma, for p-S6. All carcinomas, all differentiated VINs, and most classic VINs contained regions of p-S6 staining in the basal layer, whereas basal and parabasal cells of normal vulvar epithelium and hyperplastic and inflamed lesions lacking cellular atypia were p-S6 negative. Laminin γ2 was expressed in a subset of VINs, always occurring within basal p-S6 positive regions, as we had found previously for oral dysplasias. Lichen sclerosus is considered a potential precursor of vulvar carcinoma. Two lichen sclerosus lesions of patients with a concurrent carcinoma and one of six lichen sclerosus lesions without atypia or known concurrent carcinoma were basal p-S6 positive. In summary, there is a distinct difference in p-S6 basal cell layer staining between benign and neoplastic vulvar squamous epithelium, with consistent staining of differentiated VIN and of some lichen sclerosus lesions. These results support further studies to assess the potential of p-S6 as a biomarker to identify vulvar lesions at risk of progressing to invasive cancer.

Etiopatogenia do câncer vulvar

There are few publications in the literature about the molecular mechanisms involved in the pathogenesis of vulvar cancer. Previous and recent studies that pointed out the basic mechanisms of carcinogenesis at this site are discussed in a comprehensive way by this review article. Genetic disturbs, association with human papillomavirus (HPV) and other possible factors involved in vulvar carcinogenesis are discussed.

Squamous Neoplasia of the Vulva

Abstract Vulvar squamous neoplasia clinical management depends on the identification of low-grade squamous intraepithelial lesions (exophytic and flat condyloma), high-grade squamous intraepithelial lesions (classic and differentiated vulvar intraepithelial neoplasias [VINs]), early invasive squamous cell carcinoma, and the different squamous carcinoma morphologies and variants. This chapter provides a comprehensive review of these topics, including the key questions faced by the pathologist during the different stages of the diagnosis process of each of these lesions. Among the updates for this edition, the reader will find (1) new information on the complications of human papillomavirus (HPV) infection in children (genital warts and recurrent respiratory papillomatosis), (2) VIN terminology, gross and frozen section exams pitfalls, and (3) invasive squamous cell carcinoma prevention, clinical/epidemiological background, and outcome. Particularly, this new edition introduces the reader to a recently described category of preinvasive squamous neoplasia named differentiated exophytic vulvar/squamous intraepithelial lesions (DE-VILs or DE-SILs). Although not yet entirely clarified in respect to their pathogenesis and link to squamous carcinoma, these lesions are almost exclusively HPV negative and seen in association with HPV-negative squamous cell and verrucous carcinomas.

Variantes de lesões intra-epiteliais escamosas: relato de quatro casos

Entre a rotina de biopsias e produtos cirurgicos provenientes do colo uterino, um numero significativo de lesoes intra-epiteliais escamosas (LIE) pode causar dificuldade quanto a caracterizacao e graduacao histologica. Tais lesoes tem sido identificadas e descritas isoladamente por artigos cientificos como variantes histologicas de LIE cervicais. Sao elas a metaplasia papilar imatura atipica (MPIA) e as variantes de neoplasia intra-epitelial cervical graus II/III: queratinizante, com padrao metaplasico imaturo de crescimento e escamomucinosa. Neste artigo sao exemplificados quatro casos representativos das entidades citadas acima, provenientes das rotinas do Programa de Prevencao do Câncer Ginecologico do Estado do Parana e de um laboratorio privado especializado em patologia ginecologica de Curitiba, o Laboratorio de Citopatologia e Anatomia Patologica Annalab. Os principais criterios diagnosticos sao descritos, assim como a correlacao citologica e molecular relacionada a presenca e a localizacao do acido nucleico viral (papilomavirus humano [HPV]) nas lesoes.