Two Cases of Cutaneous Sarcomatoid Squamous Cell Carcinoma Resembling Cutaneous Giant Cell Tumor of Soft Tissue.

ABSTRACT: Cutaneous sarcomatoid squamous cell carcinoma is well-described with histology resembling pleomorphic undifferentiated sarcoma featuring collagenous or myxoid stroma with or without elements of keratinizing squamous carcinoma. This report presents 2 cases of dedifferentiated squamous cell carcinoma (SCC) composed of sheets of malignant mononuclear cells with malignant osteoclast-like multinucleated giant cells, extravasated blood, and hemosiderin resembling cutaneous giant cell tumor (cGCT). In the first case, an exophytic facial mass of a 96-year-old woman removed by shave showing extensive cGCT-like tumor but with microscopic elements of SCC in situ and positivity for cytokeratin 5/6 in the malignant spindle cells and SCC. The second case involved a 32-year-old man with a pedunculated penile mass removed by shave biopsy, displaying malignant cytology resembling cGCT, focal staining for cytokeratin AE1/AE3 and p63, and CD68 highlighting the osteoclast-like giant cells. Molecular analysis revealed CDKN2A, TP53, and TERT. Upon reexcision, case 2 showed focally invasive keratinizing SCC associated with differentiated penile intraepithelial neoplasia and lichen sclerosus. Skin specimens with an exophytic mass histologically resembling cGCT but with malignant cytology should be meticulously evaluated for elements of SCC. Molecular analysis, detecting mutations like H3F3 or HMGA2-NCOR2 fusion, can aid in distinguishing cutaneous sarcomatoid squamous cell carcinoma from GCT bone or GCT soft tissue.

Penile Analogue of Stratified Mucin-Producing Intraepithelial Lesion of the Cervix: The First Described Case. A Diagnostic Pitfall.

The authors report a case where undifferentiated (classic) penile intraepithelial neoplasia was associated with the presence of goblet cells throughout the full epithelial thickness and which later progressed into an invasive carcinoma. The lesion evolved in three consecutive biopsies from only surface epithelium occupying numerous goblet cells in the first to variably sized solid nodules in the dermis composed of atypical squamous and/or basaloid cells intermixed with numerous goblet cells in the third biopsy. Both cellular components expressed CK7 and p16 protein. Human Papillomavirus (HPV) genotyping revealed high risk HPV type 16. To the best of our knowledge, this is the first description of such a lesion occurring on the penis, which can be considered the penile analogue of cervical stratified mucin-producing intraepithelial lesion (SMILE). The correct diagnosis was rendered retrospectively, after recognition of the existence of a vulvar lesion resembling cervical SMILE. The initial biopsy was misinterpreted as extramammary Paget disease, which also constitutes the main pitfall in the differential diagnosis. Another important differential diagnosis is penile/vulvar mucinous metaplasia. The finding of atypical squamous epithelial cells positive for p16 associated with mucinous cells present throughout the full epithelial thickness is a clue to the diagnosis of penile SMILE.

Myopericytoma tumor of the glans penis.

Myopericytoma is a low grade spindle cell neoplasm largely occurring in skin. We describe the first reported case of a penile myopericytoma. Histologically, the penile tumor was composed of a perivascular proliferation of tumor cells with ovoid shaped nuclei and abundant eosinophilic cytoplasm. Immunohistochemically, the tumor was reactive for markers of smooth muscle differentiation and vascular differentiation. The tumor was noted to be negative for BRAF by immunohistochemistry and wild-type upon gene sequencing using SnaPshot. Our finding serves to expand the anatomical distribution of myopericytoma and broadens the spectrum of primary mesenchymal neoplasms that may be encountered in the penis.

Proteomics analysis of tissue samples from patients with squamous cell carcinoma of the penis and positive to human papillomavirus.

PURPOSE: The aim of this study was to identify possible protein biomarkers and/or candidates for therapeutic targets in tissues of patients with SCCP, infected by HPV, applying one dimensional electrophoresis (1DE), followed by direct mass spectrometry (MS) analysis. MATERIALS AND METHODS: Tissues from 10 HPV positive patients with SCCP and from 10 patients with HPV negative non-tumorous penile foreskins were analyzed applying 1D electrophoresis, followed by analysis with direct mass spectrometry (MS). RESULTS: Sixty-three different proteins were identified in the first group and 50 in the second group. Recognition was possible for 28 proteins exclusively detected in Group 1 and 21 proteins presented only in Group 2. CONCLUSION: Some proteins in the first group are directly involved in the development of other types of cancer, and therefore, suitable for analysis. Complement C3 protein is a strong candidate for evaluating SCCP patients.

Ki-67, mini-chromosome maintenance 2 protein (MCM2) and geminin have no independent prognostic relevance for cancer-specific survival in surgically treated squamous cell carcinoma of the penis.

UNLABELLED: What's known on the subject? and what does the study add?: Only little and partly contradictory data are currently published about the prognostic role of immunohistochemically detectable proliferation-associated biomarkers in surgically treated squamous cell carcinoma of the penis (SCCP), and no data are available at present about their usefulness for refining the delineation between different Broders' grading categories (e.g. still G2 or just G3 SCCP?). Moreover, the accuracy of various conventional histopathological parameters for predicting cancer-specific survival (CSS) in surgically treated SCCP has not been systematically evaluated yet. Based on the so far largest study cohort encompassing 158 consecutive patients with surgically treated PSCCs characterised by means of a central histopathological review, our data add the following to the currently available literature: (i) Ki-67, mini-chromosome maintenance 2 protein (MCM2), and geminin indicate a more aggressive behaviour in SCPP but do not represent independent prognostic parameters in the multivariable analysis in terms of CSS, (ii) these three biomarkers are not helpful for refining the delineation between different Broders' grading categories at the immunohistochemical level, and (iii) the conventional histopathological parameters staging, grading, nodal involvement, and lymphovascular invasion are independent prognostic parameters that together achieve a predictive accuracy of 82% for CSS. OBJECTIVE: To assess the role of cell proliferation-associated biomarkers to predict cancer-specific survival (CSS) in patients with surgically treated squamous cell carcinoma of the penis (SCCP). PATIENTS AND METHODS: A multicentre study enrolling 158 consecutive patients with surgically treated SCCP was performed. After conducting a central histopathological review, the staining profiles of Ki-67, mini-chromosome maintenance 2 protein (MCM2) and geminin were evaluated for their correlation with conventional histopathological criteria and their prognostic relevance for predicting CSS in a multivariable Cox proportional hazards regression model (median [interquartile range] follow-up 33 [6-63] months). RESULTS: Staining evaluation showed high interobserver agreement (92-96%). Ki-67 and MCM2 displayed a significant positive correlation with histological tumour grade, lymphovascular invasion (LVI) and nodal status, whereas geminin expression only correlated with tumour grade. The 5-year CSS for the entire study cohort was 62%. Univariable analysis showed a significant prognostic impact of Ki-67 (P = 0.026), MCM2 (P = 0.007), and geminin (P = 0.036). In multivariable analysis, only pT (hazard ratio [HR] 1.67; P = 0.003) and pN stage (HR 2.62; P = 0.015) as well as tumour grade (HR 1.89; P = 0.036) and LVI (HR 2.66; P = 0.028) were identified as independent prognostic parameters for CSS. The accuracy of the Cox model for CSS prediction was 0.820 (95% confidence interval 0.741-0.898). CONCLUSIONS: At present, conventional histopathological criteria remain the most powerful predictors of CSS in surgically treated SCCP. Due to overlapping staining profiles, Ki-67, MCM2 and geminin, either singly or in various combinations, failed to immunohistochemically refine the boundaries between Broders' grading categories. Ki-67, MCM2 and geminin do not represent independent prognostic parameters but reflect a more aggressive behaviour in surgically treated SCCP. Further studies are needed to clarify the currently contradictory predictive role of proliferation-associated biomarkers in terms of predicting nodal involvement in SCCPs.

P16INK4A immunohistochemistry for detection of human papilloma virus-associated penile squamous cell carcinoma is superior to in-situ hybridization.

We evaluated p16INK4A as a reliable option to detect human papilloma virus (HPV) DNA in penile tumor specimens. Formalin-fixed paraffin embedded samples of 26 patients with penile cancer and another 18 cases with non-tumorigenic lesions were stained by three different widely used commercially available chromogenic in-situ hybridization assays high-risk HPV CISH Y1443 (Genpoint, DAKO), pan HPV CISH Y1404 (Genpoint, DAKO), INFORM HPV III (Ventana, Tucson, Arizona) and p16INK4A immunohistochemistry, then compared to the known gold standard polymerase chain reaction detecting HPV 16, 18, 31, and 33. Immunoreactivity for p16INK4A was evaluated by using a 4-tiered (0, 1, 2, and 3) pattern based system. 19 cases were positive for p16INK4A, 13 of which showed a continuous transepithelial staining (pattern 3). Pan HPV ISH showed positivity in 9 cases, high-risk HPV ISH in 7 cases and INFORM HPVIII ISH in 7 cases. p16INK4A IHC pattern 3 versus pattern 0, 1 and 2 exhibited a specificity and positive predictive value of 100 percent, with a sensitivity and negative predictive value of 72 and 62 percent, respectively, which was much better than all HPV in-situ hybridization methods referred to polymerase chain reaction. p16INK4A seems to be a superior marker for the detection of HPV-associated penile squamous cell carcinoma compared to CISH tests, but is not recommend for the detection of non-tumorigenic lesions, where PCR should be used for the initial assessment.

Primary extramedullary plasmacytoma of the penis: a case report.

Extramedullary plasmacytoma involving the penis is extremely rare. Here, we describe a case of primary extramedullary plasmacytoma of the penis in a 64-year-old man who presented with a palpable penile mass. Nuclear magnetic resonance imaging revealed the presence of a large, round non-encapsulated mass in the perineum. A contrast-enhanced computed tomography scan of the pelvis showed that the mass was located in the tunica albuginea and corpora cavernosa at the base of the penis. The mass encased the urethra and demonstrated no marked enhancement during the arterial phase. The patient underwent successful surgical resection of the tumor. Histologically, the tumor was composed primarily of neoplastic plasma cells that were positive for CD38, vimentin and Ki 67. Postoperatively, the patient recovered well and exhibited no evidence of development of multiple myeloma, local recurrence or distant metastasis at 2 months post-surgery. To the best of our knowledge, our case represents the first documented case of human primary extramedullary plasmacytoma of the penis.

Lichen sclerosus and the risk of malignant progression: a case series of 159 patients.

AIM AND METHODS: We analyzed 159 stored specimens of Lichen Sclerosus (LS) collected in the period 1999-2011 from 159 patients, in order to evaluate the histological patterns, clinical outcomes and possible associations with malignancies. The histopathologic analysis revealed 145 cases (males and females) with LS alone, 7 in whom penile LS was associated with spinocellular carcinoma (SCC), and 7 in whom LS was associated with a pseudocarcinomatous-hyperplasia (PCH). Extragenital LS was found in 20% (17/85) of the males and 78% (58/74) of the females. In the cases of SCC, immunohistochemical analyses was performed. RESULTS AND CONCLUSION: The results showed very low positivity to p16INK4A and Ki-67; biomolecular PCR was positive in only two cases, and in both cases the non-oncogenic genotype HPV 100 was detected. No important additional risk factors for malignancies were found (e.g., hormones, infections, other autoimmune diseases).

The impact of cyclooxygenase-2 and vascular endothelial growth factor C immunoexpression on the prognosis of penile carcinoma.

PURPOSE: We assessed the influence of cyclooxygenase-2 and vascular endothelium growth factor-C immunoexpression on groin metastasis and cancer survival, and their association with histological variables in patients with penile carcinoma. MATERIALS AND METHODS: We evaluated the histological and cyclooxygenase-2/vascular endothelium growth factor-C immunohistochemical profiles of patients with penile carcinoma treated at a single institution between 2001 and 2008. Univariate and multivariate analysis was done to determine the impact of histological and immunohistochemical markers on the risk of inguinal metastasis and on cancer survival. Survival analysis of relevant variables was also done. RESULTS: Of the 127 patients enrolled 76 and 30 had positive cyclooxygenase-2 and vascular endothelium growth factor-C immunoexpression, respectively. Univariate analysis identified an association between vascular endothelium growth factor-C immunoexpression and groin metastasis, and certain histological variables. Logistic regression showed that high tumor grade, Jackson stage and vascular endothelium growth factor-C immunoexpression were independent predictors of inguinal metastasis. Cancer survival was only influenced by advanced Jackson stage and groin metastasis. CONCLUSIONS: Findings suggest that vascular endothelium growth factor-C expression may help identify patients with an unfavorable clinical course of penile carcinoma. Cyclooxygenase-2 did not alter the risk of groin metastasis or cancer death. Inguinal disease and advanced Jackson stage were independent prognostic factors for worse cancer survival.

The peri- and intratumoral immune cell infiltrate and PD-L1 status in invasive squamous cell carcinomas of the penis.

INTRODUCTION: Penile carcinomas are rare tumors throughout Europe. Therefore, little attention is drawn to this disease. That makes it important to study tumor-associated key metrics and relate these to known data on penile neoplasias. MATERIALS AND METHODS: A cohort of 60 well-defined penile invasive carcinomas with known human papillomavirus (HPV) infection status was investigated. Data on tumor type, grading and staging were recorded. Additionally, data on the peri- and intratumoral immune cell infiltrate in a semiquanititave manner applying an HE stain were assessed. RESULTS: Our study showed a significant correlation of immune cell infiltrate and pT stage with overall survival. Therefore, in a subset of tumors, PD-L1 staining was applied. For tumor proportion score (TPS), 26 of 30 samples (87%) were scored >0%. For the immune cell score (IC), 28 of 30 samples (93%) were defined as >0% and for CPS, 29 of 30 samples (97%) scored >0. PD-L1 expression was not associated with overall survival. CONCLUSION: PD-L1 is expressed in penile carcinomas, providing a rationale for targeted therapy with checkpoint inhibitors. We were able to show that immune reaction appears to be prognostically relevant. These data enhance the need for further studies on the immune cell infiltrate in penile neoplasias and show that PD-L1 expression is existent in our cohort, which may be a potential target for checkpoint inhibitor therapy.

Pseudoglandular (adenoid, acantholytic) squamous cell carcinoma of the penis. A case report.

A case of so-called pseudoglandular (adenoid, acantholytic) squamous cell carcinoma (SCC) of the penis occurring in a 60-year-old man is described. The tumor showed, in addition to the pattern of conventional moderately to poorly differentiated SCC, a component of tubular-appearing pseudoglandular SCC. No precancerous dysplastic lesion was found near the lesion. Immunohistochemically, the tumor cells expressed pancytokeratin, p53 and p63, and they were negative for endothelial markers, carcinoembryonic antigen and p 16. Stains for mucin were negative. Metastases were found in the regional lymph nodes and spermatic cord. Four weeks after the penectomy, multiple cutaneous/subcutaneous metastases appeared and metastases in the pelvic lymph nodes were visualized through a CT scan. The advanced stage of the tumor seen in the present case further confirms that pseudoglandular SCC represents a highly aggressive tumor.

Penile pacinian neurofibroma.

Pacinian neurofibroma (PNF) is a lobulated benign neural tumor with prominent structures resembling pacinian bodies. These tumors most commonly occur in areas where normal pacinian bodies are found, such as the hands and feet. Although pacinian bodies are common in the penis, no cases of penile PNF have been reported to date. We present a case of PNF on the dorsal glans penis of a 47-year-old man. The lesion presented as a single flesh-colored papule and the biopsy showed a dermal neurofibroma consisting of bland spindle cells with wavy nuclei, without mitoses or atypia, and some nodular structures with a concentric arrangement and a pacinian appearance. Immunohistochemistry demonstrated positivity for CD34 and Vimetin and negativity for Epithelial Membrane Antigen (EMA). S100 was highly positive in the most central areas of the pacinian-like nodules, while the periphery and non-nodular parts of the neurofibroma were less intensively expressed.

Prognostic value of p16INK4a overexpression in penile cancer.

INTRODUCTION: Penile cancer is rare, accounting for less than 1% of all male cancers in industrialized countries. It is most common in areas of high prevalence of HPV, being a third of cases attributed to the carcinogenic effect of HPV. Tumour cells infected with HPV overexpress p16INK4a, as such p16INK4a has been used as a surrogate of HPV infections. OBJECTIVE: To evaluate the prognostic factor of p16INK4a overexpression in penile cancer. METHODS: Retrospective analysis of patients diagnosed with penile cancer, submitted to surgery in a Portuguese Oncological Institution in the last 20 years (n = 35). Histological review of surgical pieces and immunohistochemical identification of p16INK4a. Relation between p16INK4a and the following factors were studied: age, histological subtype, tumour dimensions, grade, TNM stage, perineural invasion, perivascular invasion, disease free survival (DFS) and cancer specific survival (CSS). RESULTS: p16INK4a was positive in 8 patients (22.9%). Identification of p16INK4a did not correlate with none of the histopathological factors. In this work we identified a better DFS and CSS in patients positive for p16INK4a (DFS at 36 months was 100.0% vs. 66.7%; CSS at 36 months was 100.0% vs. 70.4%), although without statistical significance (p > 0.05). In multivariate analysis of histopathological factors studied, only N staging correlated with DFS and CSS (p = 0.017 and p = 0.014, respectively). DISCUSSION: the percentage of cases positive for p16INK4a is smaller than the one found in literature, which can suggest a less relevant part of HPV infection in the oncogenesis of penile cancer in the studied population. Identification of p16INK4a did not relate with other clinicopathological factors. Tendency for a more favourable prognosis in patients with p16INK4a agrees with results found in literature. The most relevant factor for prognosis is nodal staging. CONCLUSIONS: penile cancer positive for p16INK4a shows a trend for better survival, although the most relevant factor is nodal staging.

Morphology, p16, HPV, and outcomes in squamous cell carcinoma of the penis: a multi-institutional study.

Our objective was to evaluate the pathologic features and clinical outcomes in cases of invasive penile squamous cell carcinoma (SCC) and the association with p16 immunohistochemistry (IHC) and human papilloma virus (HPV) in situ hybridization (ISH). A retrospective multi-institutional database search was conducted for invasive SCC of the penis diagnosed between 2007 and 2018 that had undergone surgical resection. Pathologic features, p16 IHC, and HPV ISH were investigated with clinical outcomes. A total of 102 patients were included in the study. The average age was 63 ±â€¯13.3 years. Based on histology, 46% of tumors displayed an HPV-related subtype, whereas p16 was positive in 52% of all cases. Tumor histology correlated well with p16 positivity (P < .001), and p16 IHC accurately predicted the presence of HPV in 25/26 (96%) cases. On multivariate analysis, perineural invasion was associated with local disease recurrence (P = .02), whereas lymphovascular invasion was associated with progression to metastatic disease (P = .002) and increased overall mortality (P = .02). Urethral involvement was also associated with increased overall mortality (P = .02). In addition, HPV-related tumors based on histologic features correlated with lower rates of metastatic disease (P = .007). HPV is a common cause of penile SCC and can be diagnosed by tumor histology and confirmed by overexpression of p16 on IHC. The presence of lymphovascular invasion, perineural invasion, and urethral involvement are poor prognostic indicators, whereas HPV-related tumors based on histology may have lower risk for metastatic disease.

Granular cell tumor of the penis shaft: case report and literature review.

INTRODUCTION: Granular cell tumors (GCT) are uncommon soft tissue neoplasms of presumed neural origin that rarely involve the male external genitalia. Penile lesions are distinctly uncommon with less than 20 cases reported till now. OBJECTIVE: In the present paper we describe the clinicopathological and immunohistochemical findings in a case of GCT of the penis shaft in a 31-years-old man. RESULTS AND CONCLUSIONS: On physical examination the patient was found to have a small ovoid mass, 20 x 10 mm in diameter, at the left postero-lateral area of the penis' base. The mass was firm on palpation with no fixation on the neighboring tissues. The lesion was completely excised under loco-regional anesthesia. The surgical specimen was an ovoid, gray-white, elastic mass, of 10 x 5 mm. Microscopically, the tumor was moderately cellular and was composed of polygonal-shaped cells with abundant granular eosinophilic cytoplasm. Tumor cells were disposed in nests, cords, and trabeculae and showed perineural invasion. The tumor presented bland cytological features with only focal slight nucleo-megaly. Mitotic activity was undetectable. The tumor cells showed diffuse immunohistochemical expression for S100 protein. At 6 month after surgery the patient was free of persistent/recurrent disease or metastatic spread of the tumor. We discuss the clinical, histo-immunohistochemical and therapeutical features of this unusual penile tumor, the single one encountered in the Department of Pathology from Timisoara County Hospital and, to our knowledge, the only one reported in the Romanian medical literature.

Etiological role of human papillomavirus infection in the development of penile cancer.

OBJECTIVE: To examine the association between human papillomavirus (HPV) infection and penile cancer among Japanese patients. METHODS: Thirty-four patients with penile cancer were enrolled in this study. DNA was extracted from paraffin-embedded tumor tissue samples, and HPV-DNA tests and genotyping were performed. For all of the samples, in situ hybridization (ISH) was performed to locate HPV-DNA in tumor tissue. Furthermore, expression levels of p16-INK4a, mini-chromosome maintenance protein 7(mcm-7), HPV-L1, and Ki-67 were analyzed using immunohistochemical methods. RESULTS: HPV and high-risk (HR)-HPV were detected in 14 (41.1%; 95% confidence interval (CI) 24.6-57.7%) and 12 (35.2%; 95% CI 19.2-51.4%) cases, respectively. HPV16 was the most frequently detected HPV type. Among the HR-HPV-positive cases, a punctate HR-HPV-DNA signal pattern was detected by ISH in tumor cell nuclei. P16-INK4a was expressed in 66.7% (95% CI 42.8-90.1%) of HR-HPV-positive cases and was significantly more frequent and stronger in HR-HPV-positive cases than in HPV-negative cases. There was no significant difference in the occurrence or distribution of mcm-7 or Ki-67 expression between HPV-positive and HPV-negative cases. HPV-L1 expression was not observed in any of the cases examined. CONCLUSIONS: HPV infection may have had an etiological role in 41% of the examined cases of penile cancer in Japan.

Leiomyosarcoma of the penis presenting as a cutaneous lesion.

We report a case of a 68-year-old man with cutaneous leiomyosarcoma of the penis. Leiomyosarcoma of the penis is an extremely rare neoplasm that usually presents in middle to old age, and to our knowledge only approximately 30 cases have been reported in the literature to date. This is an important diagnosis in the differential diagnosis of cutaneous spindle cell neoplasms of the male genital tract.

Extramammary Paget disease.

A 59-year-old man presented with a well-demarcated, tender ulcer at the base of the penile shaft that had been present for approximately five years. The ulcer had been responsive neither to topical antibacterials, antifungals, and glucocorticoids nor to oral acyclovir. A biopsy specimen showed an intra-epidermal neoplasm consistent with extramammary Paget disease (EMPD) based on light microscopy and immunohistochemistry. Patients with EMPD require extensive medical evaluation because of its association with adnexal carcinoma and visceral malignant conditions. Evaluation should include a full body skin and lymph node examination, colonscopy, cystoscopy, and sex-specific studies including pelvic and breast examinations, with imaging for women and prostate examination with prostate specific antigen levels for men. Close monitoring after treatment is important because of the recognized risk of recurrence and malignant conditions.

Penile myointimoma in children and adolescents: a clinicopathologic study of 5 cases supporting a distinct entity.

Penile myointimoma is a rare benign myointimal proliferation occurring exclusively within the corpus spongiosum of the glans penis and is most commonly described in adult patients. To date, there is only one reported series of 10 penile myointimomas plus one case report, representing a total of 8 adults and 3 children/adolescents. We report 5 penile myointimomas occurring in 5 patients less than 18 years of age (age range 4 to 15 y). All patients presented with a mass lesion on the glans penis ranging in size from 0.4 to 1.8 cm. All 5 lesions had the classic morphologic appearance: myointimal proliferation of the preexisting vascular spaces of the corpus spongiosum, creating a multinodular/plexiform architecture. Immunohistochemically, all stained cases showed strong cytoplasmic immunoreactivity for smooth muscle actin in the lesional cells and a collarette of native smooth muscle highlighted by desmin. None of the lesions appeared completely excised, but all 5 patients were clinically free of disease at last clinical follow-up (2 to 45 mo). In summary, we report only the second series of this distinctive, relatively rare myointimal proliferation within the corpus spongiosum of the glans penis, expand the number of published cases occurring in the pediatric/adolescent population, and confirm the benign clinical course after a marginal or incomplete excision.

Medullary Carcinoma of the Penis: A Distinctive HPV-related Neoplasm: A Report of 12 Cases.

A third to half of penile invasive squamous cell carcinomas are human papillomavirus (HPV) related. Warty (condylomatous), warty-basaloid, and basaloid carcinomas are the most common subtypes associated with HPV. Less frequent are clear cell and lymphoepithelioma-like carcinomas. Here we report a novel penile tumor associated with HPV. Twelve cases were selected from 1010 penile carcinomas, part of an international HPV detection study conducted at the Institut Català d'Oncologia, Barcelona, Spain. Immunostaining with p16 was performed on all cases, and HPV-mRNA detection was also performed. En bloc full tumor staining was the utilized criteria for positivity of p16. For HPV-DNA detection, whole-tissue section polymerase chain reaction analysis was performed by SPF10-DEIA-LiPA25 (version 1). The patients' ages ranged from 42 to 92 years (average, 71 y). The tumor was most commonly located in the glans. A characteristic microscopic finding was the presence of a moderate to dense tumor-associated inflammatory cell infiltrate composed of neutrophils, lymphocytes, plasma cells, or eosinophils. Tumors grew in large solid sheets, nests, or had a trabecular pattern. Cells were large and poorly differentiated or anaplastic. Keratinization was minimal or absent. Nuclei were large with prominent nucleoli. Mitoses were numerous. Tumor necrosis was common. Deep invasion of the corpora cavernosa was frequent. p16 and HPV-DNA were positive in all cases, whereas mRNA detection was positive in 9 cases only. The prevalent genotype was HPV16 (9 cases, 75%). Other genotypes were HPVs 58, 33, and 66. Medullary carcinomas of the penis are morphologically distinctive HPV-related high-grade neoplasms affecting older individuals. More studies are necessary to delineate the epidemiological, clinical, and molecular features of this unusual penile neoplasm.