>> reporter: clinton's surrogates out in force, including michelle obama, knocking trump for complaining about his debate microphone. >> when she gets knocked down, she doesn't complain. she doesn't cry foul. >> reporter: but clinton's husband -- >> so you have this crazy system where all of a sudden 25 million people have health care and then the people are out there busting it, sometimes 60 hours a week, wind up with their premiums doubled a >> can you imagine what he went through after making that statement? >> reporter: bill clinton and the campaign walking that back today. >> president obama has talked about that, that obamacare needs to be improved. it doesn't need to be sacked and scrapped. >> reporter: awkward moments on the trail for republicans too. like new hampshire senator kelly ayotte, asked if she would point to trump as a good role model for children. >> and i believe he's -- he can serve >> reporter: gary johnson defending his foreign policy flub. >> you're running to be commander in chief. >> the fact that somebody can dot the is and cross the ts on a foreign leader or -- >> reporter: as clinton's lead widens, she's less worried about gary johnson taking away votes. lester? >> andrea mitchell, thank you. our primetime coverage of the vice presidential debate begins at 9:00 eas there's a new report out tonight that says the beleaguered internet giant yahoo secretly searched every incoming e-mail, snooping through hundreds of millions of its own customers' messages looking for a specific term at the request of the u.s. government. the revelation again igniting concern over privacy and our justice correspondent pete williams has late details on this. >> reporter: yahoo, one of the world's largest providers of e-mail services, messages looking for a specific term last year, according to the reuters news agency. yahoo says it's a law abiding company and complies with the laws of the united states. the decision to obey, not fight a court order was made by the ceo, the former google executive running yahoo since 2012. >> well, the news is troubling. this is precisely the type of mass surveillance that gave rise to so many objections here in the united states. europe. >> reporter: documents leaked three years ago by edward snowden disclosed that the national security agency tapped into e-mail traffic to search for specific terms connected to terrorism. but reuters says yahoo itself was doing the searching itself last year in realtime, looking for an item specified by the government. the company would have to do that search, experts say, after yahoo began encrypting traffic last year, making it impossible for the government to scans e-mail isn't new. the website spells it out, yahoo analyzes and stores content from incoming and outgoing e-mail. u.s. intelligence agencies aren't commenting tonight on what's apparently a classified program. in the past they've said they'll use all lawful means to prevent terrorism. there were terrifying moments today when an explosion leveled a pair of homes in a new jersey neighborhood. federal statistics show that gas pipe incidents have destroyed property or hurt or killed someone every other day in the u.s. for the last 20 years. is that what's behind today's blast? nbc's anne thompson now with troubling questions. >> reporter: the cause to this explosion was the hiss of gas and a rotten eggs smell. >> i said, why are you coming out of the house? he said, i smell gas, and it's a really bad odor. >> reporter: warning signs that allowed all the people in these two shattered buildings to get out heard the explosion and it was a surprise. it was such a big explosion, i couldn't believe it. >> we just had an explosion at a house. >> reporter: this cause is under investigation and some wonder if this incident, like others, was ignited by a pipeline problem. in 2010, a natural gas explosion leveled the san bruno, california, neighborhood, killing eight people. eight people died when an explosion brought down two apartment buildings in east harlem, new york, two years ago. and police dash cam ocean county, new jersey, last year. tonight the utility pseg says the gas line in this patterson, new jersey, neighborhood was replaced 30 years ago and had been routinely inspected. >> when it comes to gas and electric, if you smell something, take it as serious as it needs to be taken. >> reporter: because quick action can save lives. still ahead tonight, surprise up about his private battle with cancer. the controversial test that he says saved his life. also what investigators have we're back now with the major health revelation today from hollywood funny man ben stiller, going public about a private battle with prostate cancer, hoping to save lives by raising awareness about a saved his own life, but one that has been controversial also. here's nbc's joe fryer. >> reporter: typically funny, today ben stiller made a serious revelation. >> i had prostate cancer a couple years ago. at first, i didn't know what was going to happen. i was scared. >> reporter: stiller writes, i was lucky enough to have a doctor who gave me what they call a baseline psa test when i was about 46. as his ps a-levels rose over the years, doctors looked closer, discovering a tumor, mid range aggressive cancer. >> i learned that i was someone who had a case that could be treated. there are a lot of people who can't. >> reporter: the tumor was removed and stiller is cancer free. he said, taking the psa test saved my life, literally. stiller's surgeon offered a study that found dramatic increase in advanced prostate cancer cases as fewer men are screening for prostate cancer saves lives. >> reporter: it's a controversial issue. some orgs recommend against psa tests because they're not always reliable and can lead to overtreatment with painful side effects. the american cancer society recommends men talk to their doctor about the benefits and risk of having the test. starting at age 50 for those with an average risk, and age 45 for those at increased risk. would have been too late. >> you got very lucky. >> yeah. that's why i went from, oh, poor me, i got cancer, to, i'm so lucky. >> reporter: joe fryer, nbc news, los angeles. we are back in a a second black box has been recovered from the scene of a deadly train crash in new jersey last week. investigators hope they can learn more from it than the first black box recovered, which wasn't working. the ntsb also obtained train and the engineer's cell phone. many witnesses have said the train was speeding, but investigators have not reached a conclusion yet. an emotional day for some of the biggest names in golf as they said farewell to the king. thousands gathered for the memorial service for the legendary arnold palmer in his home state of pennsylvania. among those attending, jack nicholas and much of the usa golf team which just reclaimed the ryder cup first time since 2008. it's taken 20 years, but for some fans, the future has arrived. you can get your hands on a marty mcfly's self-lacing nikes from the movie "back to the future 2." only 89 pairs are available through a raffle. when we come back, finally tonight, we're closing in on this evening's first and only vice presidential debate of this election. as we've seen in the moments that go down in political history or infamy that we'll be talking about for decades to come. here's peter alexander. >> reporter: when it comes to memorable moments. >> that's a bunch of malarkey. >> reporter: running mates haven't always played second fiddle. take sarah palin with her unforgettable introduction to joe biden. >> nice to meet you. >> reporter: a campaign strategy after she kept calling him senator during debate prep. or benson dismiging dan quayle after he likened his own credentials to jack kennedy. >> jack kennedy was a friend of mine. senator, you're no jack kennedy. >> reporter: the devastating attack didn't stop bush from winning the white house. >> there's never been a vice presidential debate that ever changed the outcome of a presidential election. >> reporter: but they can impact how the top of the ticket is viewed. >> reporter: in 1992 ross perot came under fire for his vp pick. >> who am i? why am i here? >> reporter: his performance, a field day for "saturday night live." >> they say you're a drag on the ticket. they must have been watching a different show. when you were quiet there for an hour, that was world class. >> reporter: but the vp debates have also made history, like the first time a woman ever joined a major party ticket, setting up this dramatic du with the difference, miss ferraro between iran and the embassy in lebanon. >> i almost resent your -- >> reporter: they're number two on the ticket, but tonight on the stage, it's one-on-one. peter alexander, nbc news, washington. that's going to do it for us on a tuesday night. we'll see you tonight for our primetime coverage of the vice presidential debate at news, thank you for >> announcer: brutally beat yen left for dead. >> these scars are a constant reminder. >> announcer: will the doctors be able to erase her past? >> announcer: will her decision to live end upped destroying her life? >> i have suffered so much! upped destroying her life? >> i have suffered so much! about the mysterious death of two sisters at a luxury resort. and a vaccine that reduces cancer risk by 50%? that's today! ? ? [ applause ] ? ? >> dr. travis: hello, everyone. how y'all feeling? [ crowd cheering ] >> audience: whoo! board certified dermatologist dr. sonia batra? >> ready to bring it as usual, right? >> i hope so. >> dr. travis: we will get started. one in five americans claim to send explicit messages to one another, numbers are growing among the 50 + crowd. >> because we missed out as kid. we gotta make up for lost time. [ audience oohs ] >> there's a reason for that. [ laughter ] [ apuse ] >> dr. travis: but, this one ... drew, you with. for one woman, an unsolicited photo nearly ruined her engagement, why? because it was a nude photo from her future father-in-law. [ audience oohs ] >> dr. travis: of course she took to her blog, she got a dirty dad's pic and asked for advice. >> what do you you need advice for? he's outta here! [ applause ] >> where's the hesitation. >> how do you interpret? before a wedding. but in this case you have to address it with your fiancee. i don't think there's a question, you have to have an open line of communication. >> dr. travis: when you say he's outta here, are you saying the dat--- dad-in-law? >> yes. >> dr. travis: the groom's parents are divorced. >> he had no one else to send a picture, to, okay. >> dr. tra do you not allow that man to come to the wedding. >> address it to the fiancee, if you are the woman in that situation. in terms of marriage it sets up a pattern of communication; your husband is your partner, you have to be able to communicate even if it's so unpleasant and just so awkward t have to bring that up. >> dr. travis: do you worry about the saying "the apple doesn't fall far from the tree?". walk down the aisle and be super-excited a day later after receiving this picture. i would have a lot of hesitation. >> i think the apple doesn't fall far from the tree, but if you are embarking upon a lifetime with someone, you have to have trust and a line of communication that he's going to do the right thing. he will step in, hopefully going forward in the marriage. he will be an intermediary between you and his family and his parents. i think you have to address it. it's super-awkward, bu don't, every time you are at a family gathering, it will be so awkward and tense. you can't keep this a secret and just suck it up and go forward. >> dr. travis: i am pretty certain i can give this advice to close off this particular topic: if your son is getting married, do not send a picture of your penis to his future wife. [ laughter ] [ applause ] >> is that the take-home? wow! >> dr. travis: obvious i am saying that tongue-in-cheek. obviously. but i want to move on to a much more serious subject. heroin abuse is one of the biggest health crises, and canada is taking an approach, prescription heroin. how does it work? certified addiction specialist, ken from the a & e networks intervention. tell us, ken, what approach they are thinking of using and then, of course, your thoughts on it. >> it's a harm reduction model. and, um, i know of it really well. but i just don't believe in it. i think they should be using the intervention model. that's the model that's been working and helping the family systems come in. and really intervening on them, and getting them into recovery. harm reduction doesn't work in my opinion. >> am i correct in assuming that, it's gonna start with the vancouver clinic they want supervised setting so you don't run the risk, people can die after a heroin injection. using need wills that others have used, putting them at risk for infectious diseases. is that the idea, people are doing it in a save environment or you can wean people off of it in a safe setting? >> both. the model is both. get them in a controlled environment. and give them th but that's like giving an alcoholic a few drinks a day, and say we are gonna get him into treatment. once you feed that part of the brain for an alcoholic, they are off and running. their brain is hijacked and they can't stop. they start lying, stealing, manipulating to get anything they can to get more drugs. >> i think it's important to point out here with the canadian program it's for a select sub-group of this is not -- addicts. this is not that you sign up and get prescription strength heroin. to your point, the idea behind the program is that, these addicts who have been treatment-resistant, at least are coming into a controlled place, they have a much lower risk of overdose. much lower risk of contaminated need wills -- needles regarding hepatitis and hiv. and the study in canada shows it significantly is less way, you are not treating the overdose, and there's much less criminal activity. when you think about it, the #1 cause of accidental death in the united states is overdose from medications, this is kind of intriguing for this sub-set of patients and people. i think it's viable when you think about it. >> dr. travis: i am not adverse to the concept. where i struggle is, at what point do you move away from the treatment protocol to the and they are offering free heroin, i would think that it would be really difficult to take the next step. i think that's my part where i am struggling. >> addiction medicine, the specialty itself is evolving every day, it's getting better and better. just to make it clear, ken, is it true that methadone treatments, which has been the go-to place, fails in "x" amount of cases? >> it's the same thing. it's exactly the same thing. you know, where is that that travis is talking about? when do you change it from treatment into putting them into these types of programs? i have one down the street from our place here and there's a line every morning. they are lined up waiting for their fix. these are not like most people, they are not given the life they deserve if they were able to get into recovery. the doctors put them in there and they put them in there way too early and then they can't >> to your point, as to whether they are lining up, at least they are not out there committing crimes to raise the money to get the heroin, because they are addicts. they are so addicted they may go to lengths to get what they need, to get their fix. >> dr. travis: it's clear some people, ken, there are some individuals that, no matter how hard you try, it feels impossible; is that fair to say? >> there are a few ... but it's ry the people using methadone is a lot larger. and that's my concern. bring this heroin in, and everybody's gonna be on the same thing. they will be using methadone, heroin, and they will not get into recovery. >> dr. travis: it's a tough one. no easy answers. ken, we appreciate the work you do trying to get people healthy and better. keep up the great work! [ applause ] one of those, we will keep people abreast. because obviously this is a new way of looking at it. and to be frank, i was surprised at your opinion; but i appreciate it. i think, um, when difficult times call for difficult measures and i think it will be interesting to get data out of canada. >> to see how it plays out. >> dr. travis: the good news is, there's help out there. if you are struggling with addiction call the confidential free help line. 1-800-662 help. and we will have information on the website. quickly i want to touch on this topic. because it does relate to what we talk about on the show: that is, your health and your health history. that is yours. but hackers recently leaked medical files of some of our most popular olympians, the williams sisters, simone viles a basketball player, and the