Human papillomavirus (HPV), primarily HPV 16 & 18, are strongly implicated in the development of squamous cell carcinoma of the penis. Three carcinoma in situ are associated with squamous cell carcinoma of the penis: 1) Bowen's disease which presents as leukoplakia on the shaft. Around 1/3 progress to squamous cell carcinoma
The innate immune system is the bodyâs first line of defense against infection by microorganisms such as viruses, bacteria, and parasites.
III. Specific Body defenses (Third line of defense). A. Overview. 1. Immune system is a. functional. system rather than an organ-system with trillions of lymphocytes that circulate throughout the body. 2. Immune response. : Antigen-specific defenses mounted by activated lymphocytes (T and B cells).