Colon cancer is the commonest cancer in Hong Kong. Once colon cancer is confirmed, most patients press for surgery to remove the tumor. In the case that the tumor is found very close to the anus, surgical treatment will involve both anus removal as well as colostomy, where the colon is cut and brought through the abdominal wall to create an artificial opening for collecting waste products from the body. In recent clinical studies, observations via a watch-and-wait approach has shown to spare 70% of colon cancer patients from unnecessary surgical resections and their related surgical complications.
Dr. Stanley Yu, a specialist in clinical oncology, had been the first to introduce the watch-and-wait strategy to practice at Hong Kong Integrated Oncology Centre. He explains that, for many years, newly diagnosed colon cancer patients were primarily treated with surgery to remove the tumor. Where the rectal tumours are found low-lying, which means if they are located within less than 5 cm in proximity to the anus, the anal sphincter complex muscles and anus are removed in an operation called abdominoperineal resection (APR). After APR, patients will have to permanently wear a replaceable disposable bag outside of the body to collect body waste. Quality of life post-APR can be hugely compromised, especially for younger patients.
Dr. Yu recalls a 35-year-old male Stage II colon cancer patient who had to undergo surgical treatment for his cancer. It was evident that the tumour was situated very closely – within 4cm – to the anus as shown on magnetic resonance imaging (MRI) scans. The patient insisted on preserving his anus during surgical treatment, with hopes to avoid potential complications of surgery. At the end, the anus preserving operation was successful; however, in compensation, the anal sphincters had to be removed. This ended up causing damage to the neighbouring nerves in the anus, resulting in a loss of normal anal functions. Specifically, the anus no longer held conscious control, and the patient suffered from complications of incontinence and urinary dysfunctions. “This case study serves as a great reminder that organ preservation is not always in the best interest of every patient”, explains Dr. Yu.
Is surgery always necessary?
Speaking of Dr. Yu’s prior practising experience in the United Kingdom, he recalls coming across numerous patients whose tumour markers were within-normal-limits in response to pre-operative chemoradiotherapy. Despite such findings, these patients were still scheduled for rectal surgery, thus experience significant surgical complications of faecal incontinence, permanent stoma as well as other unnecessary morbidities. This phenomenon left Dr. Yu desperate to seek ways to defer surgery without compromising disease control – quality of life comes first for these patients.
In 2010, Dr. Yu began his own research, where the outcomes of the watch-and-wait paradigm in colorectal cancer patients were investigated. “Depending on the tumours’ staging as well as patients’ response to chemoradiotherapy, rectal surgery may be held off”, he explained. “The preliminary numbers tells us that watch-and-wait allows clinicians to see if patients really needed surgery. As such, we can save some patients from permanent lifestyle changes and favourably retain their quality of life.” Following Dr. Yu’s study, other researchers have found that tumours did not regrow in 70% of the watch-and-wait patients, thus did not require immediate rectal surgery. A whopping 95% success rate was also achieved in the remaining 30% of patients who proceeded with the operation.
Favourable statistics, favourable patients
The watch-and-wait approach is increasingly adopted in colorectal cancer treatment. “We are seeing promising results – more and more patients are benefitting from watchful waiting. These patients are able to retain as many activities of daily living as they can prior to their cancer diagnosis and treatment. They really are forever grateful”, Dr. Yu says. However, he points out that patient education is key in this approach strategy. Patients need to diligently followed up, especially so in the first year after diagnosis. In particular, patients are recommended to undergo a number of MRI scans as well as regular colonoscopy. In the case that tumours regrow, patients are urged to go ahead with surgery.
For now, the watch-and-wait approach seems to be more feasible amongst private service providers. It requires high patient compliance and flexibility, as well as heavy support from the multi-disciplinary team. In Hong Kong, watchful waiting is still in its infancy. As researchers continue to advance our understanding of tumour biology, Dr. Yu firmly believes that watch-and-wait will sooner or later become an integral part of the primary treatment modality for colorectal cancer.