Complex sentence: After it was partially removed in a 12-hour operation, he underwent 40 rounds of radiation treatments and was later pronounced cancer-free; but in 2005 the tumor recurred and he died on May 27,2006 at the age of 39.
Split into simpler sentences: After it was partially removed in a 12-hour operation, he underwent 40 rounds of radiation treatments and was later pronounced cancer-free. However, in 2005 the tumor recurred and he died on May 27,2006 at the age of 39.