## **Core Concept**
The International Federation of Gynecology and Obstetrics (FIGO) staging system is used to classify the extent of spread of cervical cancer. It is primarily based on clinical examination, imaging studies, and surgical findings. The staging helps in planning treatment and assessing prognosis.

## **Why the Correct Answer is Right**
The FIGO staging for cervical cancer involves categorizing the disease from Stage I (carcinoma confined to the cervix) to Stage IV (carcinoma extending beyond the true pelvis or involving the mucosa of the bladder or rectum). When cervical carcinoma involves the parametrium, it signifies local spread beyond the cervix but not to distant sites. According to the FIGO staging system, involvement of the parametrium corresponds to Stage II.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Stage I is incorrect because it refers to carcinoma that is strictly confined to the cervix, which does not match the scenario of parametrial involvement.
- **Option C:** Stage III involves the lower third of the vagina and/or causes hydronephrosis or non-functioning kidney, which is more extensive than parametrial involvement alone.
- **Option D:** Stage IV indicates carcinoma that has extended beyond the true pelvis or involves the mucosa of the bladder or rectum, which is also more extensive than just parametrial involvement.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that FIGO staging is clinical and does not require surgical exploration for staging. Thus, imaging and clinical examination are crucial. Also, the involvement of the parametrium is a critical factor that changes the staging from I to II.

## **Correct Answer:** . Stage II