Is laryngeal or mouth cancer life threatening?

Extremely. If you are suspecious, get to an oral surgeon immediately.
Yes it is! It is all very close to some of your major lymph chanels and it can spread into the neck and beyond. Many individuals that wait too long need neck disection where they remove lymph nodes in the neck, radiation and chemotherapy as well will follow. Have it taken care of asap, see your dentist for a check up if needed. Tell them of your concerns.
Maybe. The extent of disease indicates whether or not it is "curable". Cancer doesn't always follow the rules we would like to apply to it, but generally speaking the outlook depends on the size of the tumor, presence of spread to lymph nodes in the neck or evidence of distant spread. In advanced cases a pet/ct scan will be ordered to help determine these things.

Related Questions

Red patch inside cheek in mouth. Not swollen or painful, just raw to the touch. Been there 2 months. Lump on neck beside throat. Oral cancer?!

Almost unheard of. in a person of your age. However, infection is a real possibility. You have health insurance coverage. You should see your GP and have this checked out. Good luck! Read more...
Rare for age. Rare for age. See oral surgeon or ENT doc if you have any of these symptoms: Persistent mouth sore, persistent mouth pain, a lump or thickening in the cheek, a white/red patch on the gums, tongue, tonsil, or lining of the mouth, a sore throat, hoarseness or feeling that something is caught in the throat that does not go away, difficulty swallowing/chewing. Read more...