New Study Finds Surgical Resection of Single Colorectal Cancer Metastasis to the Lung Significantly Improves Survival

Surgical resection may significantly improve outcomes in patients with a single colorectal lung metastasis, according to a recent Houston Methodist Hospital study that suggests the procedure might be the optimal intrvention when there is no evidence of the disease outside the chest.

The retrospective analysis, which used data from the National Cancer Database, found a nearly 50% better five-year survival rate in colorectal cancer patients whose solitary metastasis to the lungs was treated surgically rather than with radiation. Surgical resection's better survival rate was even higher compared to patients who received conservative therapy, by far the most common response to such lung metastasis.

"In this select group of patients, we found that surgical resection would be beneficial," said Dr. Min Kim, head of Thoracic Surgery at Houston Methodist and the study's primary investigator. "I'm hoping this study will prompt surgeons and medical oncologists to have better discussions about these types of patients to potentially allow a higher percentage of them to undergo surgical treatment."

The study was published in the Journal of Surgical Research in May 2025.

The lungs and liver are the most common sites for colorectal cancer (CRC) metastases, with up to 18% of patients with CRC also experiencing lung metastases. Resection of colorectal cancer metastases in both organs has been controversial due to the low likelihood of containment, but Dr. Kim said that "there's a pretty big difference between one tumor and multiple, so we were interested to see if surgery improved survival among those with just one metastasis."

Between 2010-2020, 775,733 patients in the U.S. were diagnosed with CRC, according to the National Cancer Database, including 2,976 who had a single metastasis after the primary cancer was resected. Of the single metastasis patients, 305 (10%) were treated with surgery, 157 (5%) were treated with radiation therapy and 2,514 (85%) received no local treatment to the metastasis (conservative therapy).

The study's striking finding: Patients who were treated using surgical resection had a five-year survival rate of 42.7% compared to 29.7% for radiation therapy and 23.9% for conservative therapy.

Dr. Kim noted that surgical management of colorectal cancer metastases to the lungs also is controversial because patients typically have to pause other forms of treatment, such as systemic therapy, in order to undergo surgery. Since the study was retrospective, the researchers couldn't tell if patients declined surgery or were never offered surgical treatment.

"There were a lot of limitations, so we don't know why patients in the chemotherapy group were not considered for surgery or if a patient wasn't healthy enough for surgery," said Dr. Kim. "We conducted a multivariable analysis to control for these factors, but we may never know all of the factors that contributed."

However, Dr. Kim notes that technology has developed rapidly in the last few years and surgery may be a more viable consideration now than it was for some patients in the study.

"In terms of risks, surgery has become much less risky than it was in the past," said Dr. Kim. "I suspect that a lot of the patients in our sample set underwent a thoracotomy, where you make a big incision to go in and resect the cancer. We don't do that anymore. We now perform robotic minimally invasive surgery that allows us to make only four small incisions."

The study concluded that patients with solitary colorectal lung metastases without any signs of tumors outside the chest should undergo appropriate cardiopulmonary testing and multidisciplinary evaluation for surgical resection.

Dr. Kim added that a similar study looking at treatments for single CRC metastases in the liver might be beneficial.