Final answer:
Carcinoma in situ confined to the head of a pedunculated polyp with no stalk extension is primarily treated with complete surgical excision, typically through a polypectomy. This procedure has a high chance of curing the condition when the cancer is localized and has not spread beyond the head of the polyp.
Step-by-step explanation:
To treat carcinoma in situ in the head of a pedunculated polyp with no extension into the stalk, surgery is the primary method of treatment. This localized form of cancer is often curable with a complete surgical removal of the polyp, ensuring that the entire cancerous tissue is excised. As the carcinoma in situ is confined to the head of the polyp and has not spread to the stalk or other areas, the surgical excision typically involves a procedure known as a polypectomy.
A polypectomy is usually performed during a colonoscopy or endoscopy, where the doctor will use specialized instruments to snip the polyp at its base. Since there's no extension into the stalk, this suggests that the chances of complete removal and curing the condition are high, reducing the requirement for additional treatments like chemotherapy or radiotherapy, unless the histopathological examination of the polyp suggests otherwise.