Stephen King on Alien

a) Scientific grounding of Alien
Stephen King, when acknowledging Alien, saw it as a movie more firmly grounded in scientific projection than a movie such as Star Wars.

b) Chestburster perceived as a quantum leap in gruesome and as tumour imagery
In terms of horror,  he agreed that the film caused revulsion more than scream with terror but the chest burster was a quantum leap in gruesome imagery.  Over the later seventies and early eighties, he saw a spate of what he referred to as tumor movies, in that the horror imagery was related to the idea of tumours. They had things that come out of the body and look very bad to the extent  that it didn't look like something that someone would have at their supper table. And so for King, in Alien it really happens at dinner, the ultimate affront, there is a man who begins to say "I don't feel well, my stomach is upset" and then there is thing thing that sort of rips its way out of his stomach and goes scurrying off. That was for him very clear tumor imagery, and he saw ths happening in John Carpenter's The Thing remake where there are things growing inside. Other films from that time period were Scanners, Humanoids Fom The Deep, Embryo and The Beast Within. He noticed around that time that there was a lot of discussion about cancer popping up all over the place, and that David Cronenberg  in his films focused on the idea that there are things growing inside you a lot. Cronenberg studied for and got a degree in medicine, and cancer was frankly one of the things he was very worried about and King observed in Cronenberg's work that time and time again people are actually incubating parasites.

c) Comparing Alien compared to Lovecraft
He went along with the comparison to Lovecraft's writings. His view was that mankind finally was going to see the Elder Gods rather than they come to us.

1. Stephen King: Alien, for instance, is a horror movie, even though it is more firmly grounded in scientific projection than Star Wars (Danse Macabre, p36-37, 1981) 
2. Stephen King: In a Newsweek cover story titled 'Hollywood's Scary Summer' (referring to the Summer of 1979 - the summer of Phantasm,  Prophecy,  Dawn of the Dead,  Nightwing, and Alien) the writer said, that during Alien's big, scary scenes, the audience seemed more apt to moan with revulsion than scream with terror. The truth of this can't be argued; it's bad enough to see a gelatinous crab-thing spread over some fellow's face, but the infamous chest-burster scene which follows is a quantum leap in grue... and it happens at the dinner table yet. It's enough to put you off your popcorn. (Danse Macabre, p36-37,1981) 
3. Stephen King: I count it as a supernatural tale, however; I think of it as Lovecraft in outer space, mankind finally going to see the Elder Gods rather than they coming to us. 
4. Stephen King: In Alien, the constant motif of the dark barely needs mentioning. 'In Space, nobody can hear you scream,' the ad copy read; it also could have said, 'In space it is always one minute after midnight.' Dawn never comes in that Lovecraftian gulf between the stars. (Danse Macabre, p215)
5. Stephen King: In the late seventies and early eighties, we see a spate of what I think of as tumor movies. where there are things inside that come out and they look real bad. I mean they don't look like anything that you'd have at your supper table. The example that everybody remembers is Alien, where there was a fellow - and this really does happen at dinner, it's sort of the ultimate affront - who begins to say "I don't feel well, my stomach's upset" and this thing sort of rips its way out of his stomach and goes scurrying off. That seems to me to be a very clear tumor imagery. The same thing exists in John Carpenter's remake of The Thing, where again we see things that are growing inside. (Bare Bones, Conversations on Terror with Stephen King p8)
6.  Stephen King: A lot of Canadian film maker David Cronenberg's work focuses on this idea, that things are growing inside of you. Cronenberg studied for and got a degree in medicine, cancer is one of the things that he's frankly very worried about, and it shows in its work. Time and time again in his films, people are actually incubating parasites in their bodies. There's another movie called The Beast Within that expresses the same idea. (Bare Bones, Conversations on Terror with Stephen King p8)
7. Stephen King: I'll never forget the botched opening lines of A. E. Van Vogt -- a German science fiction writer, long dead, who liked to effuse a little bit. His book Slan was actually the basis of the Alien films -- they basically stole them to do that, and ended up paying his estate some money -- but he was just a terrible, terrible writer. His short story, "Black Destroyer," begins:
   Joe Fassler: On and on, Coeurl prowled!
   Stephen King: You read that, and you think -- my god! Can I really put up with even five more pages of this? It's just panting! (www.theatlantic.com/2013/07) 
8. Den of Geek: Do people read horror to see that their fears can be rationalised in supernatural terms?
   
   
   Stephen King: That’s why I tell people that I think a lot of the horror movies of the last three or four years are riddled – no pun intended - with cancer; the alien, the thing, the chestburster, the thing that incubates inside this guy is a tumour image; the same thing is true of John Carpenter’s remake of The Thing – it’s more like John Campbell’s original story, but informed with our present interests and things like that; it’s full of this kind of cancer imagery that has to do with our bodies in revolt. The same thing is true of the Cronenberg films where there are parasites inside, like kind of sexual cancer or in Scanners where the guy’s head explodes – pretty vivid tumour image. And the thing is, we’re afraid of cancer, y’know, your generation, my generation, same thing. We live in a world where the informational inflow to us, probably in one day exceeds what our grandfathers would have gotten in a year, y’know, in terms of hard information in every day’s paper. Every day there’s something else about ‘This causes cancer’, ‘That causes cancer’, ‘cancer is a virus’, or it isn’t a virus – whatever. And so consequently we live in a world where we’re afraid that if we smoke, we get lung cancer, eat too much beef, you get cancer in your intestines… the air in London supposedly causes sinus cancer; ultra violet; if we spend too much time on the Costa Del Sol, Miami Beach or wherever, you get skin cancer – it seems now to be an unescapable disease. It’s all around us, and there’s no cure for it, and this is just like, one example. The cancer of living - it kills you sooner or later. And so I don’t think it’s surprising to see these kind of images of horrible mutations actually incubating inside the human body; I mean, that’s not all horror movies, but those images have been in a lot, and I just named some: there’s Humanoids From The Deep, same thing, there’s Embryo…
   (http://www.denofgeek.com/1st November 2007)