Other drugs for cancer of unknown primary

Bisphosphonates

Bisphosphonates are drugs that are used to help strengthen and reduce the risk of breaks (fractures) in bones that have been weakened by cancer that has spread. Examples include pamidronate (Aredia^®) and zoledronic acid (Zometa^®). They are given into a vein (by IV). To treat cancer that has spread to bone, they are given once a month.

Bisphosphonates can have side effects, including flu-like symptoms and bone pain. They can also cause kidney problems, so people with kidney problems can’t use them. A rare but very distressing side effect of intravenous bisphosphonates is damage in the jaw bones. It can be triggered by having a tooth removed while getting treated with the bisphosphonate. Doctors don’t know why this happens or how to treat it, other than to stop the bisphosphonates. Having good oral hygiene by flossing, brushing, making sure that dentures fit right, and having regular dental checkups may help prevent this.

Denosumab

Like bisphosphonates, denosumab (Prolia^®, Xgeva^®) is a drug that can be used to strengthen bones and lower the risk of fractures in bones weakened by cancer spread. To treat cancer that has spread to bone, this drug is given as an injection under the skin, once a month.

Side effects include low levels of calcium and phosphate and damage to the jaw bone. This drug does not cause kidney damage, so it is safe to give to people with kidney problems.

Octreotide

Octreotide (Sandostatin^®) is a substance related to a natural hormone, somatostatin. It is very helpful for some patients with neuroendocrine tumors. If the tumor releases hormones into the blood stream, this drug can stop the hormone release. It can also cause tumors to stop growing or (rarely) to shrink. This drug is given as an injection (shot). Some versions of the drug are given 2 to 4 times a day and others once a month.