New ASCO Guidelines on Early Detection and Treatment of Colorectal Cancer in Resource-Stratified Settings

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Marcia R. Cruz-Correa, MD, PhD

Marcia R. Cruz-Correa, MD, PhD

Manish A. Shah, MD

Manish A. Shah, MD

ASCO has approved two new resource-stratified guidelines aimed at improving the early detection and treatment of colorectal cancer in all resource settings. The guidelines are a continuation of ASCO’s efforts to provide evidence-based recommendations for the management of malignancies applicable across borders, including in limited-resource settings and low- and middle-income countries. In an interview with ASCO Daily News, Marcia R. Cruz-Correa, MD, PhD, of the University of Puerto Rico Comprehensive Cancer Center, and Manish A. Shah, MD, of Weill Cornell Medical Center and New York–Presbyterian Hospital, two of the four guideline co-chairs, discussed the global impact of these new guidelines.

“Cancer is one of the most common causes of death worldwide, including among low- and middle-income countries,” Dr. Cruz-Correa said. “One key point the panel wanted to get across is that colorectal cancer screening, early detection, and treatment are relevant not only for industrialized and high-income countries, but also for low- and middle-income countries, as well as evolving economies where noncommunicable diseases, including cancer, are on the rise.”

Dr. Shah emphasized that “for the first time, we now have formal recommendations for the best screening and management approaches to the precancerous and early cancerous stages of colorectal cancer in limited-resource settings.”

Recommendations Vary Across Different Resource Settings

Dr. Cruz-Correa explained that the evolving epidemiology of cancer requires a change in the approach to cancer screening and management. Therefore, in the process of drafting the new recommendations, “the Expert Panel conducted a comprehensive review of multiple guidelines and chose those that provided a robust scientific rationale, study design, and methodology,” she said.

A modified, four-tier, resource-setting approach developed by the Breast Health Global Initiative was used for guideline development. This approach differentiates between four main types of resource settings (basic, limited, enhanced, and maximal) and allows for variations not only between countries, but between rural and urban areas within countries. New guidelines address the possible limitations across the four resource settings and define the objective parameters of screening and treatment capacities to help users determine their setting.

“Our recommendations took into consideration the available personnel and technologies offered at various clinical settings from basic to maximal, and we provided recommendations for practicing physicians across the various settings,” Dr. Cruz--Correa said. “The main message is that colorectal cancer screening reduces mortality by improving early detection and treatment and, therefore, should be provided across multiple resource-defined clinical settings.”

Highlighted Recommendations

New recommendations call for colorectal cancer screening in asymptomatic individuals aged 50 and 75 with an average risk of cancer in settings with a high colorectal cancer incidence and/or mortality or in settings with a high proportion of advanced-stage diagnoses. ASCO recommends more frequent screening in individuals with certain risk factors such as family history of colorectal cancer, familial adenomatous polyposis, inflammatory bowel disease, and Lynch syndrome.

“Early detection with fecal-based occult blood testing is the standard and preferred recommendation for colorectal cancer screening in basic and limited settings, whereas maximal and enhanced clinical settings also incorporate endoscopy-based methods,” Dr. Cruz-Correa said.

The new recommendations also address the optimal management of polyps across different resource settings. “Proper excision and pathologic analysis of polyps are critical for colorectal cancer management,” Dr. Shah said. “We were able to provide recommendations for screening based on different resource settings and on the management of colonic polyps based on several factors, including polyp morphology (pedunculated vs nonpedunculated), size, and location.”

Treatment recommendations for rectal cancer differ based on the tumor stage and resource setting. “Different recommendations are outlined for patients with locally advanced rectal cancer who may benefit from chemotherapy and radiation before surgery, versus patients who could be treated with rectal cancer surgery alone or endoscopic resection of the tumor,” he added.

In addition to outlining the optimal treatment approach based on tumor stage, ASCO addressed the management of certain complications of colon cancer, such as colon obstruction, in different resource settings.

“We emphasize the importance of completely removing the blockage whenever possible,” Dr. Shah said. “In those settings where complete removal of the tumor is not possible, we recommended that the patient be transferred to a higher-resource setting where such a procedure could be performed. Maintaining oncologic principles in resource-limited settings was the driving motivation in these recommendations.”

Clinical Utility

Dr. Shah believes that the new recommendations will be particularly useful to physicians practicing in limited-resource settings. “Physicians practicing in limited-resource settings commonly see patients with all cancers of the gastrointestinal tract; therefore, we expect that the new guidelines will be especially useful to them. The guidelines offer recommendations for situations that they might not commonly encounter,” he said. “Even when physicians are aware of the best practices for treating a specific cancer, sometimes they are simply not available to them because of resource constraints. In those situations, the guidelines offer recommendations on alternative options.”

As an example, Dr. Shah mentioned that in the United States, it is standard for patients to have colonoscopy after colon cancer resection, although this might not be the case in many limited-resource settings. “In those cases, the guidelines make alternative recommendations for screening in the follow-up period. For example, instead of obtaining a surveillance computed tomography scan of the chest, abdomen, and pelvis annually for the first 3 years after colorectal cancer surgery, in a resource-limited setting, the guideline recommends a chest x-ray and abdominal ultrasound twice in the first 3 years,” he said.

Guidelines With Global Reach

Both guidelines were drafted by a panel of 18 multidisciplinary experts and based on a review of previously adopted colorectal cancer guidelines in the United States, Europe, and Japan. A formal consensus-based process was employed to arrive at the final recommendations.

“This was an international effort, with representatives from North America, Africa, Asia, and Europe,” Dr. Shah said. “We recognize that people around the world are affected by cancer, and we aimed to provide recommendations for the best possible management of colorectal cancer at an international level.”

Dr. Shah is optimistic that, in addition to being used to inform individual patient treatment decisions, the new recommendations will also guide improvements in health systems across different countries. “We have received feedback from our international collaborators that the guidelines can be especially useful when lobbying for improvements in the health system at a national level,” he said. “Guideline recommendations provide objective goals for taking cancer care to the next level in those countries that can afford to invest and make improvements. This is the overarching impact we expect that the guidelines will have.” 

Originally published in ASCO Daily News. © American Society of Clinical Oncology. ASCO Daily News, February 25, 2019. All rights reserved.

DISCLOSURE: For full disclosures of the panel authors, visit