RECTAL cancer patients need access to better decision-making tools to assist them in making treatment choices, according to a leading colorectal surgeon.
Professor Michael Solomon, a colorectal surgeon at Sydney’s Royal Prince Alfred Hospital, was commenting on new research in the Archives of Surgery, which highlights the treatment dilemmas facing people with early stage rectal cancers. (1)
Researchers reviewed the records of 109 consecutive patients at a US hospital who underwent radical resections after their preoperative imaging suggested they had T1 or T2 rectal cancer.
Postoperative pathology found that only 11% of the T1 tumours and 28% of T2 tumours involved lymph nodes, so the researchers concluded that most of the radical surgeries were technically unnecessary because the cancer had not spread to the lymph nodes.
“In all, 89% of patients with T1 disease (31 out of 35) and 72% with T2 disease (34 of 47) underwent unnecessary radical resection”, the researchers wrote.
However, the difficulty of predicting lymph node involvement before surgery meant that local resection was not justified in T2 cases and most T1 cases.
The study found that most clinical and pathological tumour features were not useful in detecting positive lymph nodes. Only depth of tumour invasion (the T-stage system) was a significant predictor of lymph node involvement.
Professor Solomon, who is also director of the Surgical Outcomes Research Centre at the University of Sydney, said the research indicated the complexity of treatment decisions for rectal cancer patients.
“It’s difficult. It’s all a balance of probabilities. You have to balance the percentage chance that lymph nodes are involved versus the risk of 1%-2% of dying from major surgery.”
While radical resection removes the relevant lymph nodes, it is associated with significant mortality and morbidity such as incontinence, sexual dissatisfaction, impotence and, sometimes, the need for permanent stomas.
Professor Solomon said that structured guidelines were needed to improve patients’ ability to provide informed consent for treatment. “It’s a really good example of the need for better decision-making tools, where you’re balancing different probabilities such as survival outcomes and quality of life outcomes”, he said.
Treatment decisions were also complicated by the fact that about half the patients with lymph node positive rectal cancer died from the disease within 5 years, even after a radical resection, Professor Solomon said.
The US research said that local resection should only be offered to patients with superficial T1 tumours who would adhere to aggressive postoperative surveillance, or in patients unable to tolerate major surgery.
A related commentary piece in the Archives of Surgery said that more research was needed to determine when a T1 rectal cancer is “so good” that it can be treated safely by local excision alone. (2)
– Sophie McNamara
Posted 23 May 2011