U.S. Rep. Mark Takai returned to the U.S. House on Tuesday for his first vote since undergoing surgery a month ago to have a cancerous tumor removed from his pancreas.

Takai said he now begins chemotherapy, which will continue “for the next couple of months,” according to a statement from his office.

“I want to thank the many people who sent well wishes and prayers my way. Your continued support and good thoughts are appreciated,” Takai said in the statement. “It has been a pretty difficult few months, but I’m thankful for all the awesome doctors and nurses who have helped me through this.”

Takai is back to work on a “limited basis,” according to his office. He voted Tuesday in favor of the Visa Waiver Program Improvement Act of 2015, which passed 407-19 and will now be considered by the Senate.

The bill halts the United States Visa Waiver Program for people who have traveled to Syria, Iraq, Afghanistan, Iran or Sudan in the past five years. It applies to citizens of 38 countries that participate in the program. Those travelers may still enter the U.S. by applying for a travel visa prior to arrival, provided that they pass the customs screening process.

“In passing this legislation, Congress supports a moderate strategy to tighten the visa waiver program for applicants who have visited countries that are state sponsors of terrorism,” Takai said.

He added, “Our nation must reject urges to broadly categorize refugees and immigrants in the same cast as Islamic extremists. People in Hawaii remember all too clearly the way that our nation reacted to the Japanese attack on Pearl Harbor during World War II, and we must resist repeating past mistakes that we now look back on with shame.”

Takai underwent surgery Nov. 10 at the National Institutes of Health in Bethesda, Md. He has said his prognosis is good because the cancer was detected early.