As cancer progresses, the body weakens. For Venezuela and its President, Hugo Chavez, this is particularly bad news.
Given that he was rushed to Cuba for emergency surgery last month and is now battling a post-operative respiratory infection, we have to assume he has either had a resurgence of his original cancer or it has metastasised into other organs in his body.
Either way it is an ongoing battle his body may well be losing, leaving Venezuela in political limbo.
With Chavez too sick to attend his latest presidential inauguration yesterday, Venezuela's National Assembly decided to grant an indefinite extension to the oath-taking obligations.
Brazil has sought to calm frayed nerves in the region by noting that article 234 of the Venezuelan constitution limits the extension to a maximum of 180 days.
Even if Chavez is able to take the oath before the middle of June, odds are he will have to vacate the presidency within the next four years due to medical incapacity. Venezuela thus appears set for an out-of-cycle presidential election, which has created something akin to an all or nothing game for the contending political chiefs within the Chavista machine.
Vice-President Nicolas Maduro is adamant his boss is already president and that the inauguration is little more than a formality that could be completed in the Venezuelan embassy in Havana or when Chavez returns home. These options likely suit Chavez just fine for both the expected narcissistic reasons and because Maduro is his chosen successor.
The problem for the Chavistas is that National Assembly president Diosdado Cabello has a different view.
Although himself a long-time Chavez disciple, he has fallen from favour in recent years but nevertheless retains his own substantial base of supporters backing his presidential ambitions over Maduro's.
The result is vigorous jockeying for position as Maduro and Cabello both prepare to lay claim to the presidency, prompting fears within the opposition that some sort of cynical legalistic move will be used to bypass the requirement for new elections. Odds are that Venezuela will follow the letter of its constitution and have the mandated ballot in order to avoid the sort of political isolation meted out to Paraguay after it staged a coup in June 2012 last year.
The curious point is that the role Chavez will play in events has almost completely disappeared from the discussion. As far as we know, he is still conscious and lucid. This means Chavez can still have an enormous influence on political events even if he cannot resume duties as President, which creates a potentially insurmountable challenge for the opposition.
Irrespective of who seizes the Chavista candidacy, their most important campaign asset will be a visibly disease-affected Chavez reaching out from either his deathbed or the recovery room to tell his legion of acolytes how to vote.
The power of the Chavez sympathy vote was demonstrated during the December 16 gubernatorial elections when the President interrupted his emergency treatment in Cuba for a whistle-stop visit to Caracas to rally his supporters. It worked, and the number of Chavista-controlled state governments rose from 15 to 20 out of 23.
This result underlined the charismatic power of Chavez.
Even Henrique Capriles, the opposition candidate who won a surprising 45 per cent of the national vote in the October presidential elections, barely survived the Chavez sympathy vote to retain the governorship of the state of Miranda.
The implication for the opposition is clear: any election held while Chavez is still alive is probably going to be a lost cause.
Although the actual casting of ballots in any post-Chavez election campaign will be free and fair, the part open to question is the conduct of the campaign and the extent to which Chavez's shadow or ghost will hang over the rallies and marches that will fill the streets of Venezuela.
For those who simply want change or see Chavez as a persistent cancer afflicting Venezuela, the fear is that Chavezismo will metastasise into a new malignancy built around corruption and narco-trafficking.
They can only hope that Chavez's character judgment has been sound and that neither Maduro or Cabello are the nefarious criminal figures suggested by the harshest opposition critics in Venezuela and the US.
Either way, Chavez will be likely to remain the story even when he has left the scene.
