Australian researchers say they have developed a technique to attack and destroy tumours without causing such painful side effects such as nausea or hair loss.
They have used nanotechnology to create tiny particles which specifically attack cancer cells, but leave healthy tissue unaffected.
The particles - or mini-cells - are tagged with anti-cancer antibodies so they zero in on their target.
Traditional chemotherapy typically involves subjecting the patient's entire body to powerful drugs, which can cause a range of severe side-effects.
The new research features in the journal Cancer Cell.
Researcher Jennifer MacDiarmid, from Sydney-based biotechnology company EnGeneIC, said: "There is no other system where you can get so much drug concentrated into a little parcel."
In tests, the technique reduced tumours in animals without side effects - and by using only a very small amount of drug.
The mini-cells - about one-fifth the size of a normal cell -were created from bacteria cells stripped of their reproductive powers.
They were then loaded with cancer drugs, and tagged with antibodies which are attracted to cancerous tumours.
Once the cell reaches the cancer, the drug is released directly into the malignant growth.
It is hoped the technique could treat tumours in the breast, ovaries, colon and lungs.
So far it has been used in mice and dogs, and the researchers plan to begin human trials shortly.
Dr MacDiarmid said the treatment could potentially be used on any solid tumours.
She said the technique potentially paved the way for customised drug cocktails for individual patients.
Professor Quentin Pankhurst, of the London Centre for Nanotechnology, said: "The concept of targeted drug delivery is something which has been around for a while and there are many different avenues that have been tested.
"This one looks like an interesting and promising one.
"I particularly like the fact that these mini-cells, as they call them, seem to be swallowed up by the cancer cells and taken inside the cancer cells, because that is inherently a very powerful way to actually deliver the drug - actually into the cell."