ORLANDO — Colorectal cancer screening plays an important role in cancer prevention and detection, not just in the “young-old,” but also in the “old-old”—people in their eighties and beyond.
And if a cancer is found, the elderly can also derive considerable benefit from treatments including surgery and chemotherapy, two presenters said at a meeting on gastrointestinal cancers sponsored by the American Society of Clinical Oncology.
A retrospective review of 1,390 patients aged 80 years and older who were screened with colonoscopy at Mount Sinai Medical Center in Miami Beach during the last 26 years showed that the majority of cancers (74%) were caught at an early stage when they were treatable by surgery alone, Dr. Heloisa P. Soares said at the symposium, also sponsored by the AGA Institute, the American Society for Therapeutic Radiology and Oncology, and the Society of Surgical Oncology.
Treatment with chemotherapy for more advanced colon cancer was also beneficial in this elderly population, whose mean age at diagnosis was 85 years, Dr. Soares said.
In all, 98 patients received chemotherapy as part of their treatment. In patients with stage II colon cancer, chemotherapy resulted in a median overall survival of 75 months, compared with 46 months for patients treated with surgery alone. In stage III colon cancer, chemotherapy likewise improved survival, to 49 months vs. 25 months for surgery alone. However, in stage IV colon cancer, survival was similar: 9 months with and 8 months without chemotherapy.
“More than 70% of newly diagnosed colon cancer cases are in people older than 70 years. Screening in this population pays off, and so does chemotherapy, especially in the early stages,” Dr. Soares said.
In another study presented at the meeting, 161 metastatic colorectal cancer patients aged 80 years or older who were treated with bevacizumab (Avastin) and standard chemotherapy tolerated the regimen as well as their younger counterparts aged 65–79 years, and also had the same progression-free survival. After a median follow-up of 21 months, the median progression-free survival was 10 months for all patients, regardless of their age.
The only risk factors for poor outcome were poor performance status (defined as ECOG [Eastern Cooperative Oncology Group] performance status of grade 2 or greater) and a history of arterial thrombotic events.
These results, from the BRITE (Bevacizumab Regimens Investigation of Treatment Effects and Safety) prospective cohort study, show that advanced age in itself should not be considered a deterrent to treating patients, said Dr. Mark Kozloff of Ingalls Memorial Hospital, Harvey, Ill., and the University of Chicago.
BRITE's large cohort of elderly metastatic colorectal cancer patients offers a unique opportunity to analyze bevacizumab and chemotherapy treatment outcomes in a population that is poorly represented in clinical trials, he said in an interview.
“These were basically all comers, unselected patients with metastatic colorectal cancer who are age 65 and older, and just those patients that we encounter most often in our real-world clinical practices. So these data are reassuring,” he said.
Bevacizumab has been shown to prolong overall survival and progression-free survival when added to chemotherapy for metastatic colorectal cancer, but it is associated with an increase in arterial thromboembolic events.
Of 1,953 patients in the observational cohort, 896 patients were aged 65–74 years, 533 were aged 75–79 years, and the rest were aged 80 years or older.
There was a lower median overall survival for patients aged 80 years and older (16 months vs. 21 months for patients aged 65–74, and 20 months for patients aged 75–79) but this might be because of less aggressive treatment in this older cohort, Dr. Kozloff said.
Side effects with bevacizumab—such as gastrointestinal perforations, postoperative bleeding, delayed wound healing, and hypertension—were similar across all age groups.
Dr. Soares disclosed no conflicts of interest. Dr. Kozloff disclosed that he receives research funding from Genentech Inc. The BRITE study was sponsored by Genentech, which developed Avastin.
'Screening in this population pays off, and so does chemotherapy, especially in the early stages.' DR. SOARES