One obstacle is that the Codman pump requires a catheter that the Medtronic pump lacks. It’s not clear whether replacement catheters could be obtained, or whether the Food and Drug Administration would allow the adaptation.

Patients at Memorial Sloan Kettering who received the Codman pump lived about two years longer than those who did not, Dr. Kemeny and her colleagues reported last year, in the Journal of Clinical Oncology. They looked at 2,368 consecutive patients with colorectal cancer who had surgery to remove tumors that had spread to the liver. They were treated from 1992 to 2012.

Those who received pumps (785) survived a median of 67 months, compared with 44 months for patients who did not get them (1,583). The result was especially striking, Dr. D’Angelica said, because patients who got pumps were sicker to begin with.

The report was not based on the strongest type of evidence, which would come from a controlled study with patients picked at random to receive one treatment or another. But the researchers said the evidence was the strongest that could be obtained without a randomized study.

Dr. Kemeny began recommending the pump in the 1980s, and Memorial Sloan Kettering has been a leader in its use. Other centers also used it, but many stopped in the mid-to-late 1990s, thinking that improved chemotherapy would make it unnecessary. But there were still patients who needed the pump. Now, just as the device is being phased out, medical interest in it has started to rebound.

Dr. Kemeny never gave it up. She said patients came to Sloan Kettering from all over the United States and from overseas for the treatment, referred by doctors or based on their own online searches for help.

Peter Beckerman, 69, a carpenter from Holbrook, N.Y., said that after surgery for colon cancer, his doctor told him his liver was covered with tumors and he had about 20 months to live. But the surgeon also urged him to consult Dr. Kemeny.