Gradual and synergistic correlation of tumor thickness and histological grade in penile invasive carcinomas.

Histological grade and depth of invasion are among the best outcome pathological predictors in penile cancer. The TNM system is based on a combination of both for some stages. It is assumed that high-grade and deep tumors carry the worst prognosis, and the opposite occurs with superficial and low-grade neoplasms. However, there is no systematic evaluation of the phenomenon. We studied 147 patients from the Hospital de Oncologia - Instituto Mexicano del Seguro Social (period 2000 to 2013). They were treated by total or partial penectomies. Lymph node involvement was evaluated by bilateral inguinal node dissection (126 cases) or ultrasonography (21 cases). Tumor thickness was measured in mm from tumor surface to deepest invasion point, using a cut-point for superficial (≤10 mm) vs deep (>10 mm) tumors. Histological grade was from 1 to 3 according to WHO and AFIP criteria and considering G1 and G2 as low-grade and G3 as high-grade. Average age was 62 (26-98) years old. Tumor thickness mean was 15 mm (2-30 mm). G1, G2 and G3 tumors corresponded to 19 (13 %), 48 (33 %), and 80 (54 %) cases, respectively. Follow-up ranged from 10 to 82 months (median: 57 months). Fifty-three (36 %) patients died of disease. There was an overall correlation of tumor thickness and grade in most of the cases. Low-grade tumors were encountered in 92 % (12/13 cases) of superficial tumors. Deep tumors showed high-grade in 75 % of cases (73/97 cases). Superficial tumors with low histological grade had negative inguinal nodes and no mortality whereas deep tumors showing high histological grade were associated with high metastatic risk to lymph nodes (62/73 cases) and mortality (52/73 cases). Out of 24 deep tumors with low histological grade, seven had nodal spread (29 %) but only one died of disease. No outcome difference was found in HPV associated vs HPV independent tumors. Tumor thickness and grade are important synergistic and predictive pathological factors in relation to prognosis.

Penile intraepithelial neoplasia: Distribution of subtypes, HPV genotypes and p16INK4a in 84 international cases.

There are few pathologic or molecular studies of penile precancerous lesions, and the majority refers to lesions associated with invasive carcinomas. Penile Intraepithelial Neoplasia (PeIN) is classified in two morphologically and distinctive molecular groups, non-HPV and HPV-related with special subtypes. The primary purpose of this international series was to classify PeIN morphologically, detect HPV genotypes and determine their distribution according to PeIN subtypes. A secondary aim was to evaluate the p16INK4a immunostaining as a possible HPV surrogate for high-risk HPV infection in penile precancerous lesions. Samples consisted of 84 PeIN cases, part of a retrospective cross-sectional analysis of 1095 penile carcinomas designed to estimate the HPV DNA prevalence in penile cancers using PCR and p16INK4a immunostaining. Penile Intraepithelial Neoplasia (PeIN) was classified in HPV-related (basaloid, warty-basaloid, warty, hybrid, and mixed subtypes) and non-HPV-related (differentiated), the former being the most frequent. PeIN subtypes were differentiated (non-HPV-related) and basaloid, warty-basaloid, warty, hybrid and mixed (HPV-related). Basaloid PeIN was the most commonly diagnosed subtype, and HPV16 was the most frequent HPV genotype detected. Warty-basaloid and warty PeIN showed a more heterogeneous genotypic composition. Most HPV genotypes were high-risk but low-risk HPV genotypes were also present in a few cases (4%). A single HPV genotype was detected in 82% of HPV positive cases. In contrast, multiple genotypes were detected in the remaining 18% of cases. The findings in this study support the paradigm that penile in situ neoplasia, like its invasive counterparts, is HPV dependent or independent and has distinctive morphological subtypes readily identified in routine practice. Considering that HPV16 is clearly the predominant type, and that the three available vaccines have HPV16, all of them will be suitable for vaccination programs; the price of the vaccines will be probably the main determinant to choose the vaccine.

The dual pathogenesis of penile neoplasia: The heterogeneous morphology of human papillomavirus-related tumors.

Objective: Penile neoplasia, usually of squamous histogenesis, is currently classified into human papillomavirus (HPV)-related or -dependent and non-HPV-related or -independent. There are distinct morphological differences among the two groups. New research studies on penile cancer from Northern countries showed that the presence of HPV is correlated with a better prognosis than virus negative people, while studies in Southern countries had not confirmed, perhaps due to differences in staging or treatment. Methods: We focused on the description of the HPV-related carcinomas of the penis. The approach was to describe common clinical features followed by the pathological features of each entity or subtype stressing the characteristics for differential diagnosis, HPV genotypes, and prognostic features of the invasive carcinomas. Similar structure was followed for penile intraepithelial neoplasia, except for prognosis because of the scant evidence available. Results: Most of HPV-related lesions can be straightforwardly recognized by routine hematoxylin and eosin stains, but in some cases surrogate p16 immunohistochemical staining or molecular methods such as in situ hybridization or polymerase chain reaction can be utilized. Currently, there are eight tumor invasive variants associated with HPV, as follows: basaloid, warty, warty-basaloid, papillary basaloid, clear cell, medullary, lymphoepithelioma-like, and giant condylomas with malignant transformation. Conclusion: This review presents and describes the heterogeneous clinical, morphological, and genotypic features of the HPV-related subtypes of invasive and non-invasive penile neoplasia.

Evolving insights into penile cancer pathology and the eighth edition of the AJCC TNM staging system.

The majority of penile malignant tumors are squamous cell carcinomas. They are pathologically defined as epithelial neoplasms originating in the squamous cells of the inner mucosal lining of the glans, coronal sulcus or foreskin. Tumor location and site of origin is preferentially in glans (70%) followed by foreskin (25%) and coronal sulcus (5%). Despite the variable geographic distribution, pathological features of penile carcinomas in areas of high- and low-risk are similar. Penile tumors are morphologically heterogeneous. A major advance, based on biological, etiological and prognostic factors, is the 2016 WHO classification separating epithelial penile neoplasia, precancerous and invasive, in non-HPV and HPV-related.

Distribution of torsional stress between the un-replicated and replicated regions in partially replicated molecules.

DNA topology changes continuously as replication proceeds. Unwinding of the DNA duplex by helicases is favored by negative supercoiling but it causes the progressive accumulation of positive supercoiling ahead of the fork. This torsional stress must be removed for the fork to keep advancing. Elimination of this positive torsional stress may be accomplished by topoisomerases acting solely ahead of the fork or simultaneously in the un-replicated and replicated regions after diffusion of some positive torsional strain from the un-replicated to the replicated regions by swivelling of the replication forks. In any case, once replication is completed fully replicated molecules are known to be heavily catenated and this catenation derives from pre-catenanes formed during replication. Although there is still controversy as to whether fork swiveling redistributes this positive torsional stress continuously or only as termination approaches, the forces that cause fork rotation and the generation of pre-catenanes are still poorly characterized. Here we used a numerical simulation, based on the worm-like chain model and the Metropolis Monte Carlo method, to study the interchange of supercoiling and pre-catenation in a naked circular DNA molecule of 4,440 bp partially replicated in vivo and in vitro. We propose that a dynamic gradient of torsional stress between the un-replicated and replicated regions drives fork swiveling allowing the interchange of supercoiling and pre-catenation.Communicated by Ramaswamy H. Sarma.

Comparison of Human Papillomavirus Genotypes in Penile Intraepithelial Neoplasia and Associated Lesions: LCM-PCR Study of 87 Lesions in 8 Patients.

Penile intraepithelial neoplasia (PeIN) is currently classified in human papillomavirus (HPV)- and non-HPV-related subtypes with variable HPV genotypes. PeINs are frequently associated with other intraepithelial lesions in the same specimen. The aim of this study was to detect and compare HPV genotypes in PeINs and associated lesions using high-precision laser capture microdissection-polymerase chain reaction and p16INK4a immunostaining. We evaluated resected penile specimens from 8 patients and identified 33 PeINs and 54 associated lesions. The most common subtype was warty PeIN, followed by warty-basaloid and basaloid PeIN. Associated lesions were classical condylomas (17 cases), atypical classical condylomas (2 cases), flat condylomas (9 cases), atypical flat condylomas (6 cases), flat lesions with mild atypia (12 cases), and squamous hyperplasia (8 cases). After a comparison, identical HPV genotypes were found in PeIN and associated lesions in the majority of the patients (7 of 8 patients). HPV16 was the most common genotype present in both PeIN and corresponding associated lesion (50% of the patients). Nonspecific flat lesions with mild atypia, classical condylomas, and atypical condylomas were the type of associated lesions most commonly related to HPV16. Other high-risk HPV genotypes present in PeIN and associated nonspecific flat lesion with mild atypia were HPV35 and HPV39. In this study of HPV in the microenvironment of penile precancerous lesions, we identified identical high-risk HPV genotypes in PeIN and classical, flat, or atypical condylomas and, specially, in nonspecific flat lesions with mild atypia. It is possible that some of these lesions represent hitherto unrecognized precancerous lesions.

Continuous Spatial Sequences of Lichen Sclerosus, Penile Intraepithelial Neoplasia, and Invasive Carcinomas: A Study of 109 Cases.

Lichen sclerosus (LSc) with penile cancer is found in about two thirds of specimens. It has been hypothesized that LSc represents a precancerous condition. To qualify as such, in addition to cytological atypia and similarity with the invasive tumor, a spatial correlation between LSc and neoplastic lesions needs to be demonstrated. The purpose of this study was to evaluate such a spatial relationship. Circumcision (28 cases) and penectomy (81 cases) specimens were evaluated. All cases had LSc, penile intraepithelial neoplasia (PeIN), and/or invasive squamous cell carcinomas. We examined LSc in relation to invasive carcinoma, PeIN, and normal epithelia. Invasive squamous cell carcinomas, classified according to the World Health Organization criteria as non-human papillomavirus (HPV)-related and HPV-related PeIN, were present in 100 cases. Non-HPV-related (differentiated) PeIN was the most common subtype associated with LSc (89%). There were 5 spatial patterns identified: (1) LSc adjacent to PeIN (23%), (2) LSc adjacent and comprising PeIN (42%), (3) LSc next to and within invasive carcinomas (8%), (4) LSc throughout the sequence PeIN-invasive carcinoma (24%), and (5) LSc was separate (with normal tissue between the lesions) from PeIN and/or invasive carcinomas in a minority of cases (3%). LSc within the cancer was not previously described. In this series, we found 35 cases with LSc within invasive carcinomas. The striking continuous spatial relationship among LSc, PeIN, and/or invasive carcinoma as shown in this study may be a necessary (but not sufficient) condition for the hypothesis postulating LSc as a penile precancerous lesion.

The variable morphological spectrum of penile basaloid carcinomas: differential diagnosis, prognostic factors and outcome report in 27 cases classified as classic and mixed variants

Background: Basaloid carcinomas of the penis, HPV-related tumors, are morphologically less homogenous than originally thought. The study objective was to evaluate the prognostic influence of the basaloid pattern in mixed tumors. Methods: We studied 154 Mexican patients from the Hospital de Oncología, CMN, Mexico City (2000­2013) and found 27 with basaloid features in at least 20% of the sections classified as classic basaloid (8 cases), warty-basaloid (7), papillary-basaloid (5) and usual-basaloid squamous cell carcinomas (7). We evaluated patients' age, site and size of tumor, histological classification, grade, thickness, anatomical level, vascular and perineural invasion, prognostic index score and node involvement. Penile intraepithelial neoplasia in adjacent epithelia was documented. Follow up ranged from 12­78 months. Statistical methods were Fisher's exact test and Kruskal-Wallis test. Kaplan-Meier method and log-rank test were used for survival analysis. The cutoff for statistical significance was p <0.05. Results: There were not clinical differences. Microscopically types were distinctive and easy to separate. Usual-basaloid squamous cell carcinomas were smaller, thinner and rarely invaded corpora cavernosa, with a low prognostic index score. Classic basaloid, warty-basaloid and papillary-basaloid carcinomas had higher rates of vascular and perineural invasion and higher prognostic index scores. These findings correlated with the rate of nodal metastasis. The majority of patients with classic and papillary-basaloid neoplasms died from systemic metastasis (87.5 and 80%) whereas only 1 patient with usual-basaloid carcinoma died of the disease (14%). Conclusions: Basaloid carcinomas are not a single entity but a spectrum of variable histological architectures mixed with those of classic basaloid tumors. Identification of mature squamous cells in a basaloid carcinoma may be important to recognize and report because patients with these tumors may carry a better prognosis (AU)

Prevalence of an inherited cancer predisposition syndrome associated with the germ line TP53 R337H mutation in Paraguay.

The tumor suppressor gene TP53 is the most frequently mutated gene in human cancer, and the germline TP53 R337H mutation is the most common mutation reported to date. However, this mutation is associated with a lower cumulative lifetime cancer risk than other mutations in the p53 DNA-binding domain. A detailed statistical analysis of 171,500 DNA tests in Brazilian neonates found that 0.27% of the general population is positive for this mutation, and some of the estimated 200,000 Brazilian R337H carriers in southern and southeastern Brazil have already developed cancer. The present study was designed to estimate R337H prevalence in neighboring Paraguay. To address this question, 10,000 dried blood samples stored in Guthrie cards since 2008 were randomly selected from the Paraguayan municipalities located at the border with Brazil. These samples were tested for R337H mutation using the PCR-restriction fragment length polymorphism assay. This germline mutation was detected in five samples (5/10,000), indicating that the total number of R337H carriers in Paraguay may be as high as 3500. Previous studies have shown that other countries (i.e., Portugal, Spain, and Germany) presented one family with this mutation, leading us to conclude that, besides Brazil and Paraguay, other countries may have multiple families carrying this mutation, which is an inherited syndrome that is difficult to control.

HPV- and non-HPV-related subtypes of penile squamous cell carcinoma (SCC): Morphological features and differential diagnosis according to the new WHO classification (2015).

The majority of penile carcinomas are squamous cell carcinomas originating in the squamous mucosa covering the glans, coronal sulcus, or inner surface of the foreskin, the 3 latter sites comprising the penile anatomical compartments. There is a variegated spectrum of subtypes of penile squamous cell carcinomas according to recent classification schemes. Currently, because of etiological and prognostic considerations, 2 morphologically and molecularly distinctive groups of subtypes of penile SCCs based on the presence of HPV were delineated. The predominant cell composition of tumors associated with HPV is the basaloid cell, which is the hallmark and best tissue marker for the virus. Tumors negative for the virus, however, are preferentially of lower grade and keratinizing maturing neoplasms with the exception of sarcomatoid carcinoma. HPV is detected in research studies by PCR or in situ hybridization (ISH) technologies, but p16 immunohistochemical stain is an adequate and less-expensive surrogate that is useful in the routine practice of pathology. The aim of this review is to demonstrate the variable morphological phenotypic expression of penile tumors separating non-HPV- and HPV-related neoplasms and to add morphological information that will justify subclassifying squamous cell carcinomas in a number of special subtypes. A brief discussion of the differential diagnosis in each category is also provided.

Pathological factors, behavior, and histological prognostic risk groups in subtypes of penile squamous cell carcinomas (SCC).

Pathologists' contribution in the determination of prognosis in invasive penile squamous cell carcinoma is crucial. The TNM staging system is based on the identification of pathological data. There are multiple pathologically based factors believed to be important in relation to the rates of regional inguinal lymph node and specific cancer death. Among them are tumor site, size, histological subtypes, thickness or anatomical level of invasion, tumor front, and vascular or perineural invasion. The identification of these factors determines the prognostic profile of patients with penile cancer. These factors are used for the construction of pathological risk groups, prognostic index, or nomograms and are helpful in the prediction of nodal metastasis or patients' outcome. This review will describe in detail the influential pathological prognostic factors present in each tumor category emphasizing the impact of especial histological subtypes in tumor spread and final outcome. There are few studies comprehensibly addressing the relation of tumor morphology and prognosis according to histological types. We are summarizing findings of prognostic factors in 3 different series for the most common types and individual series in more recently described tumor entities. We had found a broad correlation of special subtypes of penile squamous cell carcinomas that made regional nodal status and final outcome predictable according to histological features of the tumor. These findings permitted grouping special subtypes of squamous cell carcinomas into prognosis risk groups of low, intermediate, and high. In the first category of excellent prognoses are the usual grade I, verrucous, papillary NOS, pseudohyperplastic and cuniculatum carcinomas. In the second group, there are the grade II usual, mixed and warty carcinomas. The third category of tumors, with the worst prognosis is composed of high grade usual, basaloid, warty-basaloid, papillary basaloid, and sarcomatoid carcinomas. We found that subtyping of penile squamous cell carcinoma is important to determine risk for nodal metastasis and patients' survival.

Detección de la deleción F508 del gen CFTR por la técnica de mutagénesis dirigida mediante PCR en pacientes con enfermedad fibroquística / Detection of F508 Deletion in the CFTR Gene by PCR Directed Mutagenesis in Patients with fibrocystic Ddsease

La Fibrosis quística es la enfermedad autosómica recesiva más común en la población blanca y se caracteriza por la obstrucción de conductos, principalmente en pulmón, páncreas y tracto genital. Se presenta en uno de cada 2000 a 2500 nacidos vivos y tiene una frecuencia de portadores de uno cada 20 a 25 nacidos vivos. La enfermedad es causada por diferentes mutaciones en el gen regulador de la conductancia transmembrana de la fibrosis quística (CFTR). La mutación más frecuente en el gen CFTR es la deleción de tres pares de bases (CTT) denominada F508. Este trabajo se realizó con el fin de estandarizar la técnica de mutagénesis dirigida mediante PCR (PSM) para la detección de.la mutación F508 en pacientes con fibrosis quística. El método utilizado fue validado mediante secuenciación del DNA del exón 10 en todos los individuos. Mediante este análisis genético se detectaron seis individuos con las mutaciones F508 e I507. El método implementado en nuestro laboratorio podría servir para realizar un sondeo poblacional de portadores de mutaciones para la FQ.