Occult carcinoma penis presenting as malignant pleural effusion

Area of Science:

• Oncology
• Pulmonology
• Urology

Background:

• Malignant pleural effusion (MPE) is a common oncological emergency, often associated with lung, breast, or ovarian cancers.
• Metastasis to the pleura from genitourinary malignancies is uncommon.
• The penis is an exceptionally rare primary site for cancers that metastasize to the pleura.

Observation:

• A 41-year-old male presented with left-sided malignant pleural effusion.
• Initial investigations failed to identify the primary tumor site.
• Subsequent workup revealed a hidden primary squamous cell carcinoma of the penis.

Findings:

• This case represents the first reported instance of penile carcinoma presenting initially with pleural metastasis and effusion.
• Squamous cell carcinoma of the penis, while rare, can exhibit unusual metastatic patterns.
• The diagnostic challenge in identifying the primary penile tumor in the context of MPE is highlighted.

Implications:

• This case expands the known spectrum of metastatic disease from penile cancer.
• It underscores the importance of a comprehensive diagnostic approach in cases of unexplained malignant pleural effusion, including consideration of rare primary sites.
• Further research into the mechanisms of rare cancer metastasis may improve diagnostic and therapeutic strategies.