I'm in a cabin crew and want to do breast implant. I heard that the cabin's pressure is gonna burst it. Is it true?

No, but it didn’t stop Spike TV from saying so. An episode of 1000 Ways to Die, titled “Titty Titty, Bang Bang,” showed a woman who exploded on a flight to Vegas when the liquid in her implants expanded. If this were true, wouldn’t many Hollywood actresses have exploded by now?
MythBusters, a more scientifically sound television program, had busted that myth years earlier. Their research team put implants in a hypobaric chamber, recreated the altitude at 35,000 feet, and observed that the implants expanded insignificantly. Other researchers took breast implants on a simulated trip from the bottom of the ocean to the top of Mount Everest, and the implants still didn’t burst. This means that if you went to 35,000 feet in an unpressurized airplane, your implants would be safe. Unfortunately, you would be dead in about 10 minutes from hypoxia (oxygen deficiency). 

 There are no problems from cabin pressure with breast implants. This is an urban myth that stems from a practical joke several years ago where an email was sent to Qantas cabin crew.  Resting dance are completely safe on aeroplane, once you have recovered properly from your surgery. Be advised by you surgeon how long you should wait before returning to work. 

Thank you for the question.  Breast implants are not effected by altitude or high pressure. We have many patients flying in for surgery for breast augmentation and they are able to fly home within a few days. During the recovery period, it is important to avoid any heavy-lifting and strenuous activity for the first few weeks after surgery to avoid  discomfort and/or complications. I hope this, and the attached link helps. Best wishes.