I feel a lump in the back of my throat, can it be cancer?

Maybe, maybe not. A lump anywhere in the body can be cancer, so one has to be lucky in life. In the throat, an infection is more likely than a cancer. Mono is from the ebv virus, and can cause swollen glands (lymph nodes) and big tonsils. Strep throat can do the same thing, but strep throat needs antibiotics. Some other infections can cause big lymph nodes. This all means that a trip to the doctor would be wise.
Throat lump. Many things can cause the feeling of a mass sensation in the throat. It is best to have it assessed by a doctor who can examine your throat directly and get the details from you about when you first noticed this difficulty and how it has subsequently progressed. The most common cause of this type of symptom in the throat is swollen tonsils.