CARACAS: "What pain is that?"

With that simple question, Cuban leader Fidel Castro set in motion the discovery of the cancer that has plunged Venezuelan President Hugo Chavez into the fight of his life as his country keeps a suspenseful vigil.

"I couldn't find any way to get out from under Fidel's eagle eyes. 'What's wrong, what pain is that? And he began questioning me like a father would a child (...) And he began calling doctors and (asking) opinions. He took charge," Chavez recalled on July 1, 2011, the day after he went public with his illness.

Castro, whom Chavez regards as his political mentor, soon became his "top doctor," even accompanying him to some of the chemotherapy sessions he underwent in Havana.

The Cuban capital is practically the only place the 58-year-old has received care during the long course of his sickness, despite suggestions by Brazil's former and current presidents, Luiz Inacio Lula da Silva and Dilma Rousseff, that he be seen at Sao Paulo's famed Hospital Sirio Libanes.

"In Cuba, the government guarantees him two primordial things: security and political management of information," sociologist Ignacio Avalos told AFP.

Chavez had arrived in Havana at the end of a trip to Brazil and Ecuador. He was using a cane because of a pain in his left knee, catching Castro's attention and prompting him to ask the fateful question.

After the medical exams, two emergency surgeries were ordered: one for a pelvic abscess and another to extract a cancerous tumor that Chavez described as "almost the size of a baseball."

Through the ordeal, the Venezuelan leader, who has held office since January 10, 1999, never gave up power. He continued to send his ministers instructions from Cuba, while taking advantage of his convalescence to think and read, including Friedrich Nietzsche's "Thus Spoke Zarathustra."

In a matter of weeks, Venezuelans saw a radical change in their president: Chavez appeared less frequently in public, his speeches were shorter and he traded the habits of a night owl for a healthier lifestyle marked by morning activities and a diet with added fruit and less coffee.

Additionally, the slogan "Fatherland, Socialism or Death," which for years had been his battle cry, gave way to the optimistic "we will live and we will overcome."

Still, his good humor was not affected, even when he appeared in August 2011 with his face swollen and head shaved as a result of chemotherapy. For many skeptical Venezuelans, it was confirmation that he was indeed sick.

Attempting to deny the "morbid" reports that his health had worsened, Chavez appeared in public a month later at the Miraflores presidential palace toting a baseball and glove for a workout joined by some of his ministers.

And as his followers organized dozens of religious ceremonies, including indigenous and Afro-Venezuelan rites, he confessed to be undergoing a "process of spiritual renewal."

In October 2011, Chavez declared he was cured, but his health problems resurfaced six months later, when he announced, without providing details, that he had to return to Cuba for surgery to extract another tumor in the same area as the first.

Before leaving, he said he would be back "with more life than ever."

Obliged to submit to five rounds of radiation treatment, Chavez extended his stays in Havana, but remained very active on Twitter, after opening an account on the social media network during his convalescence.

Returning on that occasion to Barinas, his home state in central Venezuela, an emotional Chavez moved his family members during an Easter mass with a wrenching appeal for more time to live.

"I say to God, if what one has lived and experienced has not been sufficient, and that (the illness) was what I needed, then I welcome it. But give me life, even if it be a burning life (...) give life because there are still things to do for this people," said Chavez, who wept during the service.

Last year in early June, he declared he was "free" of cancer, a week before registering his candidacy for another six-year term as president.

After an uncharacteristically subdued campaign for the energetic leader, who gave short speeches and rarely walked -- although on one occasion he did dance and sing with his followers -- Chavez was re-elected with 55 percent of the vote, beating opposition candidate Henrique Capriles.

After his victory, however, he admitted he had felt the effects of the illness during the campaign and did "10 percent of what I would have done without radiation treatment."

"The truth is, I was a boxer with the left hand tied and one leg tied, hopping around on one foot," he said.

After submitting to new tests in Cuba, Chavez announced a new recurrence of cancer on December 8 -- as well as the need for yet another round of surgery on the island.

Signaling the seriousness of the situation, he named Vice President Nicolas Maduro as his political successor in the event he became incapacitated by illness.

After the latest surgery, Chavez suffered a "severe pulmonary infection," the government said, raising questions about his fate.

He has not appeared in public or in photographs since the procedure, keeping his country, which was awaiting his inauguration January 10, in suspense.