Rep. Maurice Hinchey (D-N.Y.) will not seek reelection this year, his office announced Wednesday.

The 10-term lawmaker plans to formally make the announcement on Thursday in Kingston, N.Y.

His decision follows his recent treatment for colon cancer. Doctors have designated him cancer-free, according to his office.

One of the most liberal members of Congress and a member of the powerful House Appropriations Committee, Hinchey, 73, was first elected to Congress in 1992.

His district is comfortably Democratic but its lines could change when the state completes its redistricting process.

During his first run for Congress in '92, Hinchey advocated for a national health insurance system. He also co-sponsored legislation in 2008 to impeach then-President George W. Bush and was an outspoken critic of that administration. Last year he won reelection by 53 percent.

—This story was updated at 3:47 p.m.