Chase runs down Esteban's symptoms with House for three seconds, then says that Foreman's not going to leave PPTH -- he doesn't want to, and House doesn't want him to. Chase predicts that House will cave to keep him, just like he caved to keep Cameron. "Foreman's not as easy as Cameron," House says, "but, of course, who is?" The camera pans over to the heretofore unseen conference table, where Cameron is sitting with the perfect pissed-off expression on her face. "I'm in the room," she says. BRILLIANT! Things like this are why I love this show.
The conversation is cut short when Foreman enters the room and says that Marina has MS. It explains all her symptoms, although Chase points out that some of those symptoms were crossed off because they were consistent with Esteban's. Foreman shrugs that off, saying they might have the same symptoms for different reasons. Chase says they might as well just put all of Marina's symptoms back on the Whiteboard if they're going to go with that. Foreman says they can do something "productive" and put Marina on interferon to see if she improves. If she does, it's MS. Yeah, that treatment-to-prove-a-diagnosis technique works really well. Just ask Lupe. Except that you can't, because she's DEAD. Much to Chase's obvious disgust, House gives Foreman a "well done" and sends him off to give Marina some interferon. Chase is super-jealous that Foreman gets praise while he gets punched in the face, but House just tells him to go do his job. Meanwhile, House seems to be trying to hack into Foreman's email account and see what he thought was so funny.
While Foreman prepares to give Marina the interferon, Esteban says he's sure she doesn't have MS. The Cuban doctors would have found that, he says. But Foreman hates communism, so he ignores Esteban and administers the drug anyway. Of course, the warning bells of doom, a.k.a. the monitors, start tolling, and Marina starts whimpering, saying her pain is getting worse. Foreman stupidly turns her wrist over and asks if that hurts. The answer is a scream of agony and an X-ray of Marina's freshly broken wrist. Nice one, Foreman.
House asks the Cottages for suggestions about why someone's wrist would break at the slightest touch. They rule out everything except Foreman's suggestion of bone cancer. House likes this, so, of course, Chase hates it. He doesn't think they should rule out infection just because House assumes the Cuban doctors treated her for that already, especially since they don't have Marina's medical records to prove it. Chase angrily accuses House of kissing up to Foreman by agreeing with all his diagnoses, while Cameron makes an "awkward!" face. If Chase is going to start getting all bitchy and personal and unprofessional, then I'm going to start hating on him like I do Cameron. Leave the personal shit out of the workplace, people. It's really not that hard. Foreman and Chase squabble until House overrules Chase and tells them to give Marina a PET scan to confirm the cancer. You know, like they gave her interferon to confirm the MS and ended up breaking her arm. House starts to leave, but Chase ridiculously spins around and says that House's agreeing with everything Foreman says for two days won't erase Foreman's hate for House over the last three years. Meanwhile, Cameron and Foreman are standing there, like, "What's up Chase's ass? This is the most he's spoken all season." House just tells Chase that if he has nothing else to add, he can go do the PET scan.