Venezuelan President Hugo Chávez has undergone surgeries, chemotherapy and radiation treatment since June 2011 for an undisclosed type of pelvic cancer. Key moments in his medical treatment have included:


— June 30, 2011: Chávez says on television from Cuba that he had a cancerous tumor removed from his pelvic region. He later says the tumor extracted was the size of a baseball.
— July 4, 2011: Chávez returns to Venezuela, but later travels to Cuba periodically for chemotherapy and medical tests.
— Sept. 23, 2011: Chávez says he completed chemotherapy and calls the treatment successful. Says later that tests show no reappearance of cancer cells.
— Feb. 21, 2012: Chávez says his doctors found a new lesion in the same place where the tumor was previously removed, and announces plans to return to Cuba for surgery.
— Feb. 26, 2012: Chávez undergoes operation that removes the tumor from the same location in his pelvic region. Says later that follow-up tests showed the tumor was "recurrence of the initially diagnosed cancer."
— March 24, 2012: Chávez travels to Cuba to begin radiation therapy.
— April 14, 2012: Chávez travels to Cuba for second round of radiation treatment.
— April 26, 2012: Chávez returns to Venezuela following cancer treatment in Cuba, saying his latest round of therapy was successful.
— July 9, 2012: Chávez says at a news conference that tests show he is "totally free" of cancer.
— Oct. 7, 2012: Chávez wins re-election to another six-year term, beating challenger Henrique Capriles.
— Nov. 27, 2012: Chávez says he will travel to Cuba for more medical treatment. He says doctors have recommended he "begin special treatment consisting of various sessions of hyperbaric oxygenation."
— Dec. 9, 2012: Chávez announces that a cancerous tumor reappeared and that he must travel to Cuba for another operation. He says the surgery could be complicated and that if he is unable to stay on as president, Vice President Nicolás Maduro should run in an election to take his place.
— Dec. 10, 2012: Chávez travels to Cuba and undergoes surgery the next day.
— Jan. 10, 1013: Chávez misses his scheduled swearing-in ceremony, which was indefinitely postponed by lawmakers. Supporters stage symbolic inauguration in the streets of Caracas, swearing themselves in in their leader's place.
— Feb. 13, 2013: Maduro says Chávez is undergoing "extremely complex and tough" treatments.
— Feb. 15, 2013: Government shows first photos of Chávez in more than two months, says he is breathing through a tracheal tube.
— Feb. 18, 2013: Chávez returns from Cuba, tweets, "We will live and we will triumph!!" Supporters celebrate in streets. But Chávez heads immediately to a military hospital, making no public personal appearance.
— Feb. 22, 2013: Foreign Minister Elias Jaua reads long letter from Chávez to summit of African and South American leaders.
— March 1, 2013: Maduro says Chávez is receiving chemotherapy and "continues his battle for life." He describes the treatments as "intense and tough."
— March 4, 2013: Communications Minister Ernesto Villegas says Chávez has "a new and severe infection" and is in a "very delicate" condition.