General
=========================================================================

• Mixed tumor composed of neoplastic squamous nests intermingled with areas of glandular differentiation
• ICD-0: 8560/3

Diagrams
=========================================================================

Fig B: mostly squamous neoplasm (red)
with focal glandular differentiation (green)

Epidemiology
=========================================================================

• 1-2% of all penile carcinomas (Anal Quant Cytol Histol 2007;29:185)
• Mean age of 55 years (range 30-74 years)

Sites
=========================================================================

• Most common is glans but extension to coronal sulcus and inner foreskin is also common

Etiology
=========================================================================

• May originate in misplaced glandular cells in perimeatal region, in metaplastic goblet cells of foreskin mucosa or as aberrant differentiation of squamous epithelium

Clinical features
=========================================================================

• Local recurrence in up to 25% and inguinal nodal metastases in 43-50% of cases
• Low mortality rate (0-14%)

Case reports
=========================================================================

• 3 patients (ages 37, 72 and 74 years) with superficial tumors (Am J Surg Pathol 1996;20:156)

Gross description
=========================================================================

• Firm, gray-white and granular tumor

Gross images
=========================================================================

Fig A: deep invasion of lamina
propria and corpus spongiosum

Micro description
=========================================================================

• Squamous cell and glandular patterns, with squamous cell pattern usually predominating
• Both components are usually discrete but mixtures can be found
• Glands produce intraluminal and intracellular mucin
• Frequent presence of penile intraepithelial neoplasia in adjacent mucosa

Micro images
=========================================================================

Infiltrating tumor has squamous
and glandular features

Glandular portion is CEA+

Nests and differentiation

Poorly formed glands and squamous components (arrows)

Malignant glandular (arrow) and squamous components (star)

Glandular and squamous components

Separated (left); admixed (right)

Metastatic deposit

Mucicarmine

CK 5/6

Positive stains
=========================================================================

• CEA in glandular portion
• p63 in squamous component
• 34bE12 in both components

Differential diagnosis
=========================================================================

• Adenosquamous (mucoepidermoid) carcinoma of urethra: ventral in penis, restricted to periurethral tissue and corpus cavernosa
• Littre gland adenocarcinoma: ventral in penis, restricted to periurethral tissue and corpus cavernosa
• Metastatic disease: usually involves shaft, tumor emboli present (Int J Surg Pathol 2011;19:597)
• Mucoepidermoid carcinoma: mixed tumor with mucin, but no glandular or ductal structures
• Pseudoglandular (acantholytic, adenoid) carcinoma: prominent acantholysis simulates glandular spaces, but lining is composed of squamous epithelium; spaces contain necrotic debris and keratin, not mucin

This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.

All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).