Medical oncologists are apt to underestimate the resectability of liver metastases in patients with colorectal cancer and therefore often fail to refer potential surgical candidates for surgical consultation, according to a study presented at the 18th Annual Conference of the National Comprehensive Cancer Network (NCCN).1
For metastases limited to the liver, resectability can often be curative. Thus, it is important for oncologists to identify appropriate surgical candidates.
Ongoing Controversy
“Despite published surgical guidelines concerning definitions of resectability, there is still controversy about which patients are optimal candidates for immediate resection and when such patients should have a surgical consultation,” said Michael A. Choti, MD, of Johns Hopkins University, Baltimore.
This study explored medical oncologists’ assessment of the technical aspects of resectability by using a standard clinical scenario to control for oncologic variability while varying the anatomic parameters of metastatic size, number, and distribution of liver metastases. Investigators recruited 200 medical oncologists (190 evaluable) from the Network for Oncology Communication and Research to participate. All had been practicing for 5 to 35 years and saw an average of 15 patients with colorectal cancer per month. The participants were queried regarding a single patient profile with 10 different sets of liver CT images, representing liver metastases of varying extent.
On reviewing the images and a summary radiologic report, respondents were asked to assess resectability based on their expectation that all gross disease could be resected. They designated each case as currently resectable, potentially convertible with chemotherapy response, or unresectable. They were also asked whether surgical consultation was warranted. Their recommendations were compared with those of an expert panel of three hepatic surgical oncologists.
Medical Oncologists Miss Resectable Cases
“While the rank order of potentially resectable disease was similar between medical oncologists and expert surgeons, the medical oncologists were much less likely to consider a patient resectable compared to the expert panel,” Dr. Choti reported. “Even among resectable or convertible patients, medical oncologists were less likely to recommend initial surgical consultation. In situations in which the medical oncologist considered patients to be clearly resectable, initial resection was recommended only 62% of the time.”
Three tumors were deemed most resectable by the expert panel, but only 89%, 64%, and 63% of the medical oncologists, respectively, thought so. All three of these scan sets showed disease restricted to one lobe of the liver and the presence of two or fewer lesions in total. About 50% of the medical oncologists considered these cases to be potentially convertible to resectability after a significant response to systemic therapy. About 40% deemed the cases to be unresectable as displayed now or after a chemotherapy response.
Overall, medical oncologists’ resectability ratings were congruent with those of the expert surgeons in only 37% of the cases. For all cases considered to be resectable (8 of the 10), only 50% of the medical oncologists would have recommended surgical consultation, Dr. Choti reported.
Significant Inconsistencies
“Even with increasing awareness regarding the benefit of multimodality therapy for potentially curable patients with colorectal liver metastases and NCCN guidelines regarding management, significant inconsistencies continue to exist among clinicians regarding the definition of resectability, the need for surgical consultation, and the use of preoperative chemotherapy in potentially resectable liver-limited metastatic colorectal cancer patients,” he concluded.
He suggested future studies should evaluate the reasons for this discordance with expert opinion, and added that oncologists clearly need more education on this topic. ■
Disclosure:Dr. Choti reported no potential conflicts of interest.
Reference
1. Choti MA, Green MR, Wong SL, et al: Medical oncologists’ assessment of resectability in patients with liver-limited metastatic colorectal cancer. Abstract AB2013-3. Presented March 15, 2013.
