Cecilia Lezcano

BRAF Inhibition Is Associated with Enhanced Melanoma Antigen Expression and a More Favorable Tumor Microenvironment in Patients with Metastatic Melanoma

Purpose: To evaluate the effects of BRAF inhibition on the tumor microenvironment in patients with metastatic melanoma. Experimental Design: Thirty-five biopsies were collected from 16 patients with metastatic melanoma pretreatment (day 0) and at 10 to 14 days after initiation of treatment with either BRAF inhibitor alone (vemurafenib) or BRAF + MEK inhibition (dabrafenib + trametinib) and were also taken at time of progression. Biopsies were analyzed for melanoma antigens, T-cell markers, and immunomodulatory cytokines. Results: Treatment with either BRAF inhibitor alone or BRAF + MEK inhibitor was associated with an increased expression of melanoma antigens and an increase in CD8+ T-cell infiltrate. This was also associated with a decrease in immunosuppressive cytokines [interleukin (IL)-6 and IL-8] and an increase in markers of T-cell cytotoxicity. Interestingly, expression of exhaustion markers TIM-3 and PD1 and the immunosuppressive ligand PDL1 was increased on treatment. A decrease in melanoma antigen expression and CD8 T-cell infiltrate was noted at time of progression on BRAF inhibitor alone and was reversed with combined BRAF and MEK inhibition. Conclusions: Together, these data suggest that treatment with BRAF inhibition enhances melanoma antigen expression and facilitates T-cell cytotoxicity and a more favorable tumor microenvironment, providing support for potential synergy of BRAF-targeted therapy and immunotherapy. Interestingly, markers of T-cell exhaustion and the immunosuppressive ligand PDL1 are also increased with BRAF inhibition, further implying that immune checkpoint blockade may be critical in augmenting responses to BRAF-targeted therapy in patients with melanoma. Clin Cancer Res; 19(5); 1225–31. ©2013 AACR.

Bevacizumab plus Ipilimumab in Patients with Metastatic Melanoma

Hodi and colleagues report the safety and efficacy of targeting angiogenesis and CTLA-4 in a phase I trial of 46 patients with metastatic melanoma, which revealed the influence of VEGF-A blockade on inflammation, lymphocyte trafficking, and immune regulation, and their synergistic therapeutic effects. Ipilimumab improves survival in advanced melanoma and can induce immune-mediated tumor vasculopathy. Besides promoting angiogenesis, vascular endothelial growth factor (VEGF) suppresses dendritic cell maturation and modulates lymphocyte endothelial trafficking. This study investigated the combination of CTLA4 blockade with ipilimumab and VEGF inhibition with bevacizumab. Patients with metastatic melanoma were treated in four dosing cohorts of ipilimumab (3 or 10 mg/kg) with four doses at 3-week intervals and then every 12 weeks, and bevacizumab (7.5 or 15 mg/kg) every 3 weeks. Forty-six patients were treated. Inflammatory events included giant cell arteritis (n = 1), hepatitis (n = 2), and uveitis (n = 2). On-treatment tumor biopsies revealed activated vessel endothelium with extensive CD8+ and macrophage cell infiltration. Peripheral blood analyses demonstrated increases in CCR7+/−/CD45RO+ cells and anti-galectin antibodies. Best overall response included 8 partial responses, 22 instances of stable disease, and a disease-control rate of 67.4%. Median survival was 25.1 months. Bevacizumab influences changes in tumor vasculature and immune responses with ipilimumab administration. The combination of bevacizumab and ipilimumab can be safely administered and reveals VEGF-A blockade influences on inflammation, lymphocyte trafficking, and immune regulation. These findings provide a basis for further investigating the dual roles of angiogenic factors in blood vessel formation and immune regulation, as well as future combinations of antiangiogenesis agents and immune checkpoint blockade. Cancer Immunol Res; 2(7); 632–42. ©2014 AACR.

The basaloid cell is the best tissue marker for human papillomavirus in invasive penile squamous cell carcinoma: a study of 202 cases from Paraguay.

Human papillomavirus (HPV) has been reported in 12-82% of penile squamous cell carcinomas (SCC). There is an association of the virus with basaloid and warty carcinomas but the reported prevalence is variable. The causes of these variations are not clear. They may be owing to geographic differences, the use of different techniques to detect HPV, the status of the original paraffin blocks, or to variable criteria in tumor classification. The aims of the study were to determine the prevalence of HPV in penile SCC and subtypes using a sensitive technique, to investigate genotypes involved, and to search for other morphologic features associated with the virus from a series of cases from Paraguay. HPV detection was done by SPF-10 polymerase chain reaction followed by DNA enzyme-immunoassay and genotyping by LIPA 25 (version 1). Samples were tested at Catalan Institute of Oncology, Barcelona, and cross testing was carried out at the Delft Diagnostic Laboratories in The Netherlands. HPV was detected in 64 of 202 cases (32%). Thirteen tumors had multiple HPV genotypes. Most prevalent genotypes were HPV-16 (46 cases), HPV-6 (6 cases), and HPV-18 (4 cases), either in single or in multiple infections. HPV was preferentially associated with warty-basaloid (82%), basaloid (76%), and warty (39%) carcinomas and not detected in verrucous, mixed verrucous-papillary, pseudohyperplastic, and pseudoglandular SCCs. There was a strong association between HPV and higher histologic grade. Basaloid cells were more frequently found in HPV positive tumors (72%) and this association was statistically significant in univariate and multivariate analyses. Cells with koilocytotic features and keratinizing squamous cells were also present but to a much lesser degree (47% and 19%, respectively). In summary, HPV was found in a third of the cases and the most common genotype was HPV-16. Low-risk genotypes were rarely found in single infections, representing 4 cases among all analyzed (2%). There was an association between HPV presence and higher histologic grade and with basaloid, warty-basaloid, and warty carcinomas. Our results also suggest that, in penile SCC, the basaloid cell is the best tissue marker for oncogenic HPV infection.

Distinctive association of p16INK4a overexpression with penile intraepithelial neoplasia depicting warty and/or basaloid features: a study of 141 cases evaluating a new nomenclature.

From the pathogenic point of view, penile cancers may be grouped in human papillomavirus-related and unrelated tumors, each one of them with distinctive morphologic features. The former are predominantly composed of small, undifferentiated basaloid cells, with more or less prominent koilocytic changes, and the latter of keratinizing differentiated squamous cells. The same cellular types are observed in precancerous lesions. On the basis of these observations, we constructed a novel nomenclature for penile precancerous lesions and classified them as penile intraepithelial neoplasia (PeIN) of differentiated, warty, basaloid, and warty-basaloid types. The aim of this study was to test the usefulness of immunohistochemical p16INK4a overexpression, considered as a surrogate for high-risk human papillomavirus infection, using this classification system. We pathologically evaluated 141 patients with PeIN, associated (123 cases) and unassociated (18 cases) with invasive cancer. Distribution of PeIN types was: differentiated, 72%; basaloid, 9%; warty-basaloid, 7%; warty, 4%; and mixed, 7%. There was a striking similarity in the morphology of in situ and invasive squamous cell carcinomas. Differentiated PeIN was commonly associated with usual, verrucous, papillary, and other low-grade keratinizing variants of squamous cell carcinoma whereas in basaloid and warty carcinomas the presence of in situ lesions with similar morphology was habitual. We evaluated p16INK4a overexpression using a 4-tiered (0, 1, 2, and 3) pattern-based system. To properly distinguish differentiated PeIN from in situ lesions with warty and/or basaloid features only pattern 3, which requires full-thickness staining in all epithelial cells, was considered positive. Using this approach, there was a significant association of the negative patterns and differentiated PeIN and of the positive pattern and warty, basaloid, and warty-basaloid PeIN (P<0.0001). Basaloid variant had the strongest association. The sensitivity rate of p16INK4a positivity for discriminating types of PeIN was of 82%, with a specificity of 100% and an accuracy of 95%. Lichen sclerosus was identified in 42 cases and their epithelial component was p16INK4a negative in all cases. Although more studies are necessary to confirm these observations, p16INK4a overexpression seems to be a useful tool for discriminating differentiated from warty, basaloid, and warty-basaloid PeIN.

Comparison of morphologic features and outcome of resected recurrent and nonrecurrent squamous cell carcinoma of the penis: a study of 81 cases.

Penile squamous cell carcinoma (SCC) is considered a loco-regional disease with a fairly predictable pattern of progression. Widespread dissemination occurs in at least one-third of the patients. Local recurrence (defined as the presence of tumor after a primary treatment affecting any remainder tissue, including skin, erectile corpora, or urethra) present in up to 30% of the patients increases the risk of regional inguinal and pelvic lymph nodes metastases. The aim of this study was to identify adverse pathologic prognostic factors in patients with recurrent tumors. Clinicopathologic features of 81 surgically treated patients (25 with recurrent and 56 with nonrecurrent SCC) were evaluated; 56 patients (19 with recurrent and 37 with nonrecurrent tumors) additionally received groin dissections. Follow-up (2 to 372 mo, mean of 71 mo) was obtained in all patients. Comparison of recurrent tumors at the time of the primary diagnosis and of recurrence showed that histologic subtype and grade were identical in 76% of the cases and converted to a higher grade tumor in 24% of the cases, especially, in patients treated with local excisions and circumcisions. Most of the recurrences (67%) seemed at or before 12 months. Comparison of recurrent and nonrecurrent tumors showed that high grade tumors (basaloid and sarcomatoid) tended to be significantly associated with recurrent tumors, whereas low grade variants (papillary, warty and verrucous) were more frequent in the nonrecurrent group; recurrent tumors invaded into deeper anatomic levels than nonrecurrent tumors. The incidence of inguinal lymph node metastasis was higher in recurrent tumors (79% vs. 49%, P=0.0272). Cancer-specific survival was of 46% versus 76% at 3 years of follow-up in recurrent and nonrecurrent tumors, respectively. Patients with recurrent tumors had a median survival of 2.9 years; no major changes in survival were noted after 3 years of follow-up. Mortality was higher in the recurrent group (56% vs. 29%, P=0.0188); 80% of patients with high-grade tumors (basaloid, sarcomatoid, and high grade usual or hybrid verrucous SCCs) died from penile cancer. Mortality in patients with usual SCC was higher in the recurrent group, but similar in basaloid and sarcomatoid SCCs. After 3 years there was no survival difference in patients with low-grade recurrent tumors; however, in the high grade recurrent group there was a progressive and gradual decrease in survival from 2 to 10 years (median survival of 2.5 y). In summary, histologic subtypes and grades of SCCs were similar in the majority of original and recurrent carcinomas. Inguinal metastasis and mortality were higher in recurrent than in nonrecurrent carcinomas. Basaloid, sarcomatoid, and mixed usual-verrucous variants and invasion of corpora cavernosa or preputial skin were significant adverse prognostic factors of recurrent carcinomas. Local excision and partial penectomy were not adequate procedures for sarcomatoid and basaloid penile carcinomas. Carcinomas of foreskin had a better prognosis. Conversion from low to high-grade carcinoma was related to significant mortality. The identification of the adverse prognostic factors found in this study should be the base for an aggressive initial therapy to prevent recurrence in a subset of penile cancers. Re-excision of the recurrent tumor permitted the control of the disease only in one-third of the patients.

Loss of 5-hydroxymethylcytosine correlates with increasing morphologic dysplasia in melanocytic tumors

DNA methylation is the most well-studied epigenetic modification in cancer biology. 5-hydroxymethylcytosine is an epigenetic mark that can be converted from 5-methylcytosine by the ten-eleven translocation gene family. We recently reported the loss of 5-hydroxymethylcytosine in melanoma compared with benign nevi and suggested that loss of this epigenetic marker is correlated with tumor virulence based on its association with a worse prognosis. In this study, we further characterize the immunoreactivity patterns of 5-hydroxymethylcytosine in the full spectrum of melanocytic lesions to further validate the potential practical application of this epigenetic marker. One hundred and seventy-five cases were evaluated: 18 benign nevi, 20 dysplastic nevi (10 low-grade and 10 high-grade lesions), 10 atypical Spitz nevi, 20 borderline tumors, 5 melanomas arising within nevi, and 102 primary melanomas. Progressive loss of 5-hydroxymethylcytosine from benign dermal nevi to high-grade dysplastic nevi to borderline melanocytic neoplasms to melanoma was observed. In addition, an analysis of the relationship of nuclear diameter with 5-hydroxymethylcytosine staining intensity within lesional cells revealed a significant correlation between larger nuclear diameter and decreased levels of 5-hydroxymethylcytosine. Furthermore, borderline lesions uniquely exhibited a diverse spectrum of staining of each individual case. This study further substantiates the association of 5-hydroxymethylcytosine loss with dysplastic cytomorphologic features and tumor progression and supports the classification of borderline lesions as a biologically distinct category of melanocytic lesions.

Autophagy Gene Atg16l1 Prevents Lethal T Cell Alloreactivity Mediated by Dendritic Cells

Atg16L1 mediates the cellular degradative process of autophagy and is considered a critical regulator of inflammation based on its genetic association with inflammatory bowel disease. Here we find that Atg16L1 deficiency leads to an exacerbated graft-versus-host disease (GVHD) in a mouse model of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Atg16L1-deficient allo-HSCT recipients with GVHD displayed increased T cell proliferation due to increased dendritic cell (DC) numbers and costimulatory molecule expression. Reduced autophagy within DCs was associated with lysosomal abnormalities and decreased amounts of A20, a negative regulator of DC activation. These results broaden the function of Atg16L1 and the autophagy pathway to include a role in limiting a DC-mediated response during inflammatory disease, such as GVHD.

Distinctive immunohistochemical profile of penile intraepithelial lesions: A study of 74 cases

Several classification schemes for penile precancerous lesions have been proposed, but none of them seems to correlate with the current understanding of penile cancer pathogenesis. Recently, a system, which takes into account morphologic features and purported etiopathogenesis, was proposed, separating penile intraepithelial neoplasia (PeIN) in differentiated and warty/basaloid subtypes. This study was designed to seek an immunohistochemical profile that can be helpful in the classification and differential diagnosis of penile epithelial abnormalities and precancerous lesions using the aforementioned system. The immunohistochemical panel included stains for p16INK4a, p53, and Ki-67. For p16INK4a immunostaining, only full-thickness positivity in all epithelial cells was considered as positive; for p53 and Ki-67 immunostaining, patchy or diffuse nuclear positivity above the basal layer was considered as positive. Seventy-four lesions in 59 patients were selected and classified as follows: differentiated PeIN, 34 cases; squamous hyperplasia (SH), 21 cases; basaloid PeIN, 15 cases; and warty PeIN, 4 cases. The mean age of patients was 64 years. Forty-two lesions (56.8%) were located in the glans and 32 (43.2%) in the foreskin. Overexpression of p16INK4a was useful for distinguishing SH from warty/basaloid PeINs (0% vs. 94.7%, P<0.0001) but not SH from differentiated PeINs (0% vs. 5.9%, P=0.519). In addition, p16INK4a allowed the distinction of differentiated and warty/basaloid PeINs (5.9% vs. 94.7%, P<0.0001). Immunohistochemistry results for p53 allowed the separation of SH and differentiated PeIN (9.5% vs. 44.1%, P=0.0078) and SH and warty/basaloid PeIN (9.5% vs. 55.6%, P=0.0042). Ki-67 immunostain was useful for distinguishing SH from differentiated PeIN (52.6% vs. 89.7%, P=0.0062) and SH from PeIN with warty and/or basaloid features (52.6% vs. 100%, P=0.0011). There seems to be a distinctive immunohistochemical profile for associated and precursor epithelial lesions of the penis. SH was p16INK4a and p53 negative, with variable Ki-67 positivity. Differentiated PeIN was p16INK4a negative and Ki-67 positive, with variable p53 positivity. Basaloid and warty PeINs were consistently p16INK4a and Ki-67 positive, with variable p53 positivity. The use of a triple p16INK4a/p53/Ki-67 immunohistochemical panel was found to be helpful in the classification, differential diagnosis, and morphologic standardization of penile intraepithelial lesions.

Distribution and characterization of subtypes of penile intraepithelial neoplasia and their association with invasive carcinomas: a pathological study of 139 lesions in 121 patients

We are presenting the morphological features of 121 cases of atypical penile intraepithelial lesions. The term penile intraepithelial neoplasia (PeIN) was used to encompass all of them, and lesions were classified into 2 major groups, differentiated and undifferentiated. The latter was further divided in warty, basaloid, and warty-basaloid subtypes. Ninety-five cases were associated with invasive squamous cell carcinomas. Differentiated lesions predominated (68%), followed by warty-basaloid (14%), basaloid (11%), and warty (7%) subtypes. Multifocality was found in 15% of the cases. Differentiated lesions were preferentially located in foreskin, whereas warty and/or basaloid subtypes were more prevalent in the glans. The former lesions were preferentially seen in association with keratinizing variants of squamous carcinoma, whereas the latter subtypes were found mostly in conjunction with invasive warty, basaloid, and warty-basaloid carcinomas. Lichen sclerosus was present in 51% of cases of differentiated lesions and absent in warty and/or basaloid subtypes. In summary, PeIN can be classified into 4 distinctive morphological subtypes. The proper pathological characterization of these lesions may provide important clues to the understanding of the pathogenesis and natural history of penile cancer.

Comparison of Subtypes of Penile Squamous Cell Carcinoma From High and Low Incidence Geographical Regions

There is a worldwide geographical variation in the incidence of penile squamous cell carcinoma (PSCC); some subtypes are HPV-related (warty, basaloid) while others (keratinizing variants) are not. The aims of this study were to compare the distribution of different histological subtypes of PSCC from regions of low (Paraguay, 144 cases) and high (USA, 157 cases) incidence and to identify and compare tumors with and without warty and/or basaloid morphology. The distribution of subtypes in the Paraguayan and the American series was: usual, 49.3 and 46.5%; verrucous, 8.3 and 7.6%; papillary NOS, 7.6 and 5.7%; warty, 6.9 and 8.3%; basaloid, 4.2 and 7.0%; sarcomatoid, 0.7 and 0.6%; adenosquamous, 3.5 and 0.6%; and mixed, 19.4 and 23.6%, respectively. The distribution of mixed PSCC was: warty-basaloid, 50.0 and 59.5%; usual-verrucous, 21.4 and 21.6%; usual-warty, 14.3 and 8.1%; usual-basaloid, 7.1 and 0.0%; usual-papillary, 3.6 and 5.4%; and others, 3.6 and 5.4%, respectively. In conclusion, we found no geographical difference in the incidence of histological subtypes (p = 0.6501), mixed PSCC (p = 0.5937) or HPV-related tumors (p = 0.2505). Geographical variation may be the result of staging variation at clinical presentation or of pathological diagnosis. The identification of similar histological subtypes in both series validates this classification approach for penile cancer. The tendency for typical SCC to mix with verrucous and papillary carcinomas and of the basaloid to preferentially mix with benign condyloma and condylomatous (warty) carcinomas would support the hypothesis of the existence of an etiologically different dual population of penile tumors.