(Reuters) - A 75 percent reduction in the size of a tumor in former Brazilian President Luiz Inacio Lula da Silva's throat has surprised his doctors and could put the popular showman back on the active political roster as early as March.
The medical team treating Lula at the Hospital Sirio-Libanes said they were "impressed" with his recovery, as the 66-year-old former union boss started his third and final round of chemotheropy on Monday.
"It was an extraordinary reduction (75 percent) that surprised the medical team," said oncologist Artur Katz, adding that a 30 to 40 percent shrinkage would have been a positive response to treatment.
Lula completed his second and final consecutive four-year term as Brazil's president in 2010 but still wields considerable political influence at home and abroad.
His quick recovery will only enhance his messionic image among Brazil's poor and certainly raise the possibility in analysts' and politicians' eyes that he could run again, as early as 2014, if President Dilma Rousseff passes on re-election.
But even if he doesn't, Lula plays a vital role in his left-leaning Workers' Party, which will be contending for municipal elections in 2012.
He has also been a powerful advisor and peacemaker for Rousseff this year as she deals with infighting in her ruling coalition and weathers the resignation of now seven ministers, six of them due to corruption scandals.
Lula is due to follow up his chemotheropy with a series of radiation treatments in January and February but, if he continues improving, his doctors say he will be able to return to politics as early as March.
He will also likely retain full capacity of one of his defining traits as a public speaker - his burly, booming voice.
"Surgery is totally ruled out," said Kalil Filho, one of Lula's physicians, in light of the considerable shrinkage of the tumor on his larynx.
Lula's diagnosis in late October shocked Brazilians and raised debate about political life without the country's first blue-collar president, who remains a charismatic force in Latin America's largest economy.
Before taking office in January, Rousseff, Lula's anointed successor, was herself treated successfully for lymphatic cancer at the same medical center that is treating Lula.
(Additional reporting and writing by Reese Ewing, editing by Anthony Boadle)
