Human papilloma virus (HPV) serotype most often associated with invasive carcinoma cervix is:
**Core Concept**
Human papillomavirus (HPV) is a sexually transmitted virus that causes cervical cancer by integrating its DNA into the host cell genome, leading to uncontrolled cell growth and tumor formation. The HPV serotypes are classified based on their oncogenic potential, with high-risk types being more frequently associated with invasive cervical carcinoma.
**Why the Correct Answer is Right**
HPV type 16 is the most common high-risk serotype associated with invasive cervical carcinoma, accounting for approximately 50-60% of all cervical cancer cases. This is due to its ability to integrate into the host genome and express the E6 and E7 oncogenes, which disrupt the normal cell cycle and promote tumor growth. The E6 protein binds to and degrades p53, a tumor suppressor protein, while the E7 protein binds to and inactivates retinoblastoma protein (Rb), a cell cycle regulator.
**Why Each Wrong Option is Incorrect**
**Option A:** HPV type 6 is a low-risk serotype commonly associated with genital warts, but not with invasive cervical carcinoma.
**Option B:** HPV type 18 is another high-risk serotype, but it is less common than HPV type 16 in cervical cancer cases.
**Option C:** HPV types 31 and 33 are also high-risk serotypes, but they are not as frequently associated with invasive cervical carcinoma as HPV type 16.
**Clinical Pearl / High-Yield Fact**
It's essential to note that HPV vaccination is highly effective in preventing cervical cancer, and the Centers for Disease Control and Prevention (CDC) recommends routine vaccination of all females aged 11-26 years with either the quadrivalent (Gardasil) or bivalent (Cervarix) HPV vaccine.
**Correct Answer: D. HPV type 16.**