The American Society of Clinical Oncology (ASCO) released a set of resource-constrained guidelines for treating patients with late-stage colorectal cancer.
The guidelines, published in JCO Global Oncology, were decided on by a multidisciplinary, multinational expert panel that reviewed existing guidelines, conducted a modified ADAPTE process, and used a formal consensus process with additional experts for 2 rounds of formal ratings.
“The ASCO Expert Panel underscores that health care practitioners who implement the recommendations presented in this guideline should first identify the available resources in their local and referral facilities and endeavor to provide the highest level of care possible with those resources,” the authors wrote.
The panel concluded that in basic and limited settings, symptom management for late-stage colorectal cancer includes symptom control, surgical evaluation, transfusion, and palliative care. Diagnosis of this disease type should include biopsy, pathology, and endoscopy in limited settings only. Moreover, depending on the resource settings, some of the options discussed were endoscopy, digital rectal exam, and imaging.
Most patients with late-stage colorectal cancer should receive treatment with chemotherapy, where chemotherapy is available, as the optimal systemic treatment in the first line, according to the panel. Then, following a period of chemotherapy, should patients become candidates for surgical resection with curative intent of both primary tumor and liver or lung metastatic lesions based on evaluation in multidisciplinary tumor boards, it is recommended that patients undergo surgery in centers of expertise.
In basic and limited settings, if patients are at high risk of obstruction, significant bleeding perforation, or tumor-related symptoms, the optimal treatment for patients with late-stage colorectal cancer is resection of the primary tumor; however, if the primary tumor is obstructed or there are peritoneal metastases, the panel recommends diverting ostomy. In enhanced and maximal settings, the guidelines added the option of colon or rectal stenting.
For those in enhanced and maximal settings only, if patients with metastatic rectal cancer have a symptomatic primary rectal tumor, radiation therapy, with or without chemotherapy, should be discussed. Further, patients who have previously received surgery or ablation may receive systemic therapy if available.
For patients with late-stage colorectal cancer who have already received 1 prior line of therapy, chemotherapy is recommended in enhanced and maximal settings; however, this recommendation is conditional upon what patients received in the first line. For those who have received two prior lines of therapy, systemic therapy options are presented in maximal settings, though also conditional upon prior treatment.
“Clinical trials are underway in the use of immunotherapy in maximal-resource settings, and the aforementioned systematic review-based ASCO guideline may review the primary literature for targeted therapies in maximal settings, which is outside of the scope of this guideline,” the authors wrote.
The panelists suggested that, in maximal settings only, options be presented for patients with late-stage colorectal cancer and liver metastases. However, the recommendations should be implemented in centers of expertise in the specific technique after multidisciplinary review, or in the context of a clinical trial.
In regard to on-treatment surveillance and follow-up strategies for patients treated for mCRC, a combination of taking the medical history, performing physical examinations, blood work, and imaging was recommended, though specifics, including frequency, depend on resource-based setting.
Notably, the panelists indicated that clinicians should discuss the use of less-expensive alternatives with patients when it is practical and feasible for treatment of the patient’s disease and there are 2 or more treatment options that are comparable in terms of benefits and harms.
“Patient out-of-pocket costs may vary depending on resource setting,” the authors wrote. “When discussing financial issues and concerns, patients should be made aware of any financial counseling services available to address this complex and heterogeneous landscape.”
Additionally, there were limited guidelines which systemically reviewed and/or found high-quality data published to inform some of the recommendations, including:
- Best treatment of patients with metastatic rectal cancer in resource-constrained settings
- Role of primary-site radiation therapy
- Liver metastases–directed therapies
- Lung metastases–directed therapies
- Use of imaging in liver metastases
- Role of targeted therapy, including patients who received anti-VEGF or anti-EGFR in first line
- Systematic review–based guidelines including BRAF targeted therapy and/or MEK targeted therapy
- Systematic review–based guidelines including immune checkpoint inhibitors (e.g., nivolumab, pembrolizumab, ipilimumab)
Ongoing trials could lead to the need for further updating of these guidelines, at which time an additional ASCO systematic review-based guideline review would be performed by the expert panel.
Chiorean EG, Nandakumar G, Fadelu T, et al. Treatment of Patients With Late-Stage Colorectal Cancer: ASCO Resource-Stratified Guideline. JCO Global Oncology. doi:10.1200/JGO.19.00367.