Novel Histologic Finding: Adipose Tissue Is Prevalent Within Penile Tunica Albuginea and Corpora Cavernosa: An Anatomic Study of 63 Specimens and Considerations for Cancer Invasion.

Adipose tissue, along with arteries, veins, and peripheral nerves, is a normal constituent of mesenchymal tissues encasing the corpora cavernosa at the level of the penile shaft, variously designated as penile fascia or Bucks fascia. To our knowledge, the presence of fat has not been previously reported within the corpora cavernosa. One or 2 transversal histologic sections at the level of the surgical margin at the shaft of 63 consecutive partial penectomy specimens for squamous cell carcinoma were evaluated. From outer to inner tissues, 3 anatomic levels were identified: (1) outer fascia composed of a loose fibrovascular mesenchyme containing some nerve branches. Adipose tissue was present in the majority of the cases. (2) The tunica albuginea, a thick and dense fibroelastic band of tissue separating the outer fascia from the erectile tissues of the corpora cavernosa. Adipose tissue within the albuginea was present in 21 specimens (19%). (3) Erectile tissues of corpora cavernosa. Besides the typical erectile tissues, adipose tissue was present in 33 cases (52%). The fatty tissue was focal or multifocal and scant and peripherally located at the junction of the tunica albuginea with the corpora. In some cases, it was associated with small amounts of fibrous tissue, small vessels, and nerves. We are reporting the presence of adipose tissue in the tunica albuginea and the corpora cavernosa. It is possible that adipose tissue, along with small nutritional vessels and nerves perforates from the fascia, in which fat is usually present, through the tunica albuginea to reach the corpora. In a previous examination of the local routes of cancer spread, we found this pathway to be one of the mechanisms of cancer invading the penile corpora from the penile fascia.

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.