**Question:** In which case Anterior resection is the method of treatment -

A. Colonic cancer involving the rectum and lower third of the rectum
B. Rectal cancer extending into the anal canal
C. Rectal cancer involving the upper two-thirds of the rectum
D. Rectovaginal fistula

**Correct Answer:** A. Colonic cancer involving the rectum and lower third of the rectum

**Core Concept:** Anterior resection is a surgical procedure for the treatment of rectal and lower third rectal cancer. This procedure involves resecting the affected portion of the rectum and anastomosing the remaining healthy rectal segment with the colon.

**Why the Correct Answer is Right:** Anterior resection is chosen for tumors located in the rectum and lower third of the rectum because these tumors are easily accessible for surgical excision through a lower anterior abdominal incision. The procedure ensures complete removal of the tumor (R0 resection) and allows for adequate staging of the tumor. Anastomosing the rectal stump with the colon reduces the risk of anastomotic leak and stoma formation.

**Why Each Wrong Option is Incorrect:**

A. Colonic cancer involving the rectum and lower third of the rectum: This option is correct as explained above.
B. Rectal cancer extending into the anal canal: This option is incorrect because this type of cancer typically requires a low anterior resection or a proctocolectomy with ileostomy, depending on the tumor stage and patient's condition.
C. Rectal cancer involving the upper two-thirds of the rectum: This option is incorrect because this type of cancer requires a high anterior resection or a low anterior resection with a temporary colostomy, depending on the tumor stage and patient's condition.
D. Rectovaginal fistula: This option is incorrect because a rectovaginal fistula is typically managed by a colostomy rather than an anterior resection, followed by surgical repair of the fistula after healing of the abdomino-perineal wound.

**Clinical Pearl:** When choosing an appropriate surgical procedure for rectal cancer, consider the tumor location, stage, and patient's condition. Involving a colorectal surgeon during the decision-making process can lead to optimal treatment outcomes and minimize complications.