Although rectal cancer is a life-threatening disease, it is highly curable in its early stages. Depending on the location and state of the cancer, surgery may be required. To avoid life-altering consequences associated with traditional rectal surgery, physicians are increasingly using treatment options designed to improve outcomes and increase the chances of preserving organs.

Traditionally, rectal cancer surgery has involved either a low anterior resection – removing the part of the rectum containing the cancer and reconnecting the remaining part of the rectum to the colon (anastomosis) – or an abdominoperineal resection where surgeons will remove the anus, rectum and part of the sigmoid colon and attach the end of the intestine to an opening in the surface of the abdomen, called a colostomy. 

While these surgical options can be life-saving, they can have profound impacts for a patients’ quality of life. If the anus and rectum are removed, the patient will permanently have to live with a colostomy bag to collect body waste.

To avoid the complications of these invasive surgeries, UCSF colorectal surgeons offer a robotic transanal minimally invasive surgery, also known as TAMIS, for removal of rectal polyps and early-stage rectal cancers (stage 0 and stage 1). TAMIS is performed robotically through the rectum with special microsurgical instruments with a longer reach and better visibility into the rectum than traditional surgery techniques. By performing this minimally invasive procedure, surgeons can remove lesions high inside the rectum and no abdominal incision is required.

“With robotic TAMIS, there is no abdominal incision so there is less risk of infection, hernia and other post-surgical complications,” said Mark Zhao, MD, a colorectal cancer surgeon and UCSF assistant professor of Clinical Surgery. “Patients can often go home the same day, recover faster and return to their regular activities more quickly. There is no anastomosis, and the patients maintain the majority of the rectum, so patients often enjoy much improved quality of life.”

Up to 50% of patients benefit

TAMIS is only possible in early-stage disease, and most patients present with locally advanced rectal cancer (stage 2). To improve organ preservation and allow these patients to have a better quality of life, UCSF physicians are employing a “watch-and-wait” treatment strategy with chemo-radiation, as known as total neoadjuvant therapy (TNT).

“Watch-and-wait is becoming the new standard of care for some patients with locally advanced rectal cancer,” said Zhao. “Combining chemotherapy and radiation before surgery allows time to observe the clinical response prior to surgery, and in some cases, the tumor is completely treated without the need for radical surgery. Watch-and-wait provides an exciting opportunity for organ preservation for appropriate patients, potentially providing a much-improved quality of life to rectal cancer patients.”

As a premier research institute, UCSF physicians participated in the multi-center Organ Preservation in Patients with Rectal Adenocarcinoma trial (OPRA), a phase 2, randomized clinical trial that uses total neoadjuvant therapy (TNT) in patients with locally advanced rectal cancer. OPRA showed that in these patients, up to 50% of patients may achieve organ preservation without an apparent detriment in survival.

“The OPRA trial results and National Comprehensive Cancer Network (NCCN) guidelines for locally advanced rectal cancer treatment endorse watch-and-wait for patients with clinical complete response after neoadjuvant therapy,” said Zhao. “Our protocols follow established NCCN guidelines for active surveillance and go beyond the standards of the OPRA trial.”

Zhao says that the strict surveillance schedule evaluates patients for potential tumor regrowth and the need for possible salvage surgery. In the first two years, UCSF clinicians perform a flexible sigmoidoscopy, a CT and an MRI of the patient every three months. For the next three years, the evaluations spread out to every six months.

Studies have shown that watch-and-wait can be curative, and UCSF Health continues clinical research in this area to ensure the best long-term outcomes for their rectal cancer patients.

Visit UCSF Health’s rectal cancer program for more information about treatment options.

About UCSF Health: UCSF Health is recognized worldwide for its innovative patient care, reflecting the latest medical knowledge, advanced technologies and pioneering research. It includes the flagship UCSF Medical Center, which is a top-ranked specialty hospital, as well as UCSF Benioff Children’s Hospitals, with campuses in San Francisco and Oakland, Langley Porter Psychiatric Hospital and Clinics, UCSF Benioff Children’s Physicians and the UCSF Faculty Practice. These hospitals serve as the academic medical center of the University of California, San Francisco, which is world-renowned for its graduate-level health sciences education and biomedical research. UCSF Health has affiliations with hospitals and health organizations throughout the Bay Area. Visit www.ucsfhealth.org. Follow UCSF Health on Facebook or on Twitter.

This article was originally published November 8, 2024, by the University of California, San Francisco News Center. It is republished with permission.