Pocket Oncology (Pocket Notebook Series), 1st Ed.

PENILE CANCER

Melody Smith and Dean Bajorin

Definition

• Often presents as a painless lump or ulcer on the penis

• Majority consist of 1° epithelial SCC

Epidemiology

• Rare in industrialized countries & more common in less developed nations (J Am Acad Dermatol 2006;54:369)

• In US, less than 1% of CA in men

• Disease of older men w/mean dx of 60 y but not uncommon among younger men

Molecular Biology

• Mt in p16 & p53 a/w the development of penile CA

• Increased expression of protein p16NK4A, w/c is encoded by p16 gene, has been seen as a late event of HPV infxn

Risk Factors

• No circumcision or performed at an older age, single, never married, phimosis, HPV or HIV infxn, prior h/o genital warts, h/o penile injury or trauma, known urethral stricture, poor hygiene, tobacco exposure

Diagnosis

• Require careful examination of penis & palpation of inguinal LN

• Need bx of penile CA 1° ± bx of inguinal LN

Prognostic Factors

• Prognosis dictated by grade, stage, lymphovascular invasion, palpable LN (Urology 2010;76:S15)

Workup

• Bx of penile lesion is needed for T stage

• Staging of inguinal nodes is performed by FNA, DSNB (Urologic oncology 2012. pii: S1078–1439 [Epub ahead of print]), or superficial inguinal node dissection

• Staging of regional nodes in men w/a clinically negative inguinal exam is based on risk of occult nodal mets

• Risk of inguinal node positivity is greater w/T2 or greater

• Low-risk disease w/clinically suspicious adenopathy

• Clinically negative nodes does not r/o metastatic disease

• High-risk disease w/clinically suspicious adenopathy

• Nodes can be evaluated by FNA, SNB or superficial inguinal node dissection

• Positive FNA, SNB, or dissection warrants definitive surgical tx

Staging

• Stage I: Involvement of the connective tissue

• Stage II: Involvement of the erectile tissue or to the urethra

• Stage III: Any positive LN

• Stage IV: Spread to tissues near the penis, pelvic area, pelvic LNs, or distant spread

Management

• 1° goal of management is to eliminate malignancy while ensuring a cosmetically acceptable & functional penis

• T stage

• T1: Management of 1° is largely surgical w/a wide local excision but brachytherapy can be considered

• T2 or greater: Partial or total penectomy

• Local disease: Organ preserving strategies can be considered optimally for tumors that are Tis, Ta, or T1 grade 1–2 or for select distal T2–T3 tumors

• Regional disease: Chemotherapy followed by surgery

• Met disease: Chemotherapy ± radiotherapy

• Common chemotherapeutic agents (Urology annals 2012;4:150)

• Cisplatin

• Paclitaxel

• Ifosfamide

• 5-FU

• Combination Rx is frequently used

• Bulky disease (node size ≥4 cm) or unresectable LAN: Proceed w/medical tx

Prognosis in Metastatic Disease

• Median OS 6 mos. Met disease is uncommon until late in the disease course, 1–10% of cases p/w stage IV disease.