Table 2. Penile squamous cell carcinoma subtypes.

Type	Frequency (%)	Features	Spread	HPV-link
Usual	48–65	Low-grade, minimal nuclear atypia	Superficial	No
Papillary	5–15	Low-grade, hyperkeratosis, papillomatosis	Superficially invasive into erectile tissue	No
Warty	7–10	Koilocytes and fibrovascular core with papillomatosis and jagged irregular stromal borders	Penetration of corpus cavernosum or spongiosum	Yes
Basaloid	4–10	Ulcerated, irregular mass with uniform and small basaloid cells; central necrosis with predominance of mitotic figures and evidence of apoptosis	Deeply invasive into corporal bodies	Yes
Verrucous	3–8	Low-grade with straight papillae and well-differentiated cells, hyperkeratosis with inter-papillary keratin	Superficial pushing borders	No
Sarcomatoid	<1	Ulcerated or rounded polypoid mass with squamous and spindle cell components, mimicking features of sarcomas	Deeply invasive into surrounding tissues	No

The above table describes the various subtypes found in penile carcinoma and the relative frequencies of these subtypes in the general population. The histological features associated with these cancers differentiate them through pathological evaluation. The aggression of spread varies by subtype and is depicted above to show means of spread as well as associated with the human papillomavirus (HPV). This table has been referenced with permission from (30).