Shedding Light on the Unknown: New Understandings in Cancers that Can't Be Identified


A cancer diagnosis by itself is devastating. But when doctors are unable to pinpoint where it started, the cancer is harder to treat and many patients and their families struggle to cope with the often quick decline in health. A new study at Huntsman Cancer Institute (HCI) is shedding light on how genetics play a role in this type of diagnosis, and what families can do about it.

Cancers of unknown primary (or CUP) origin account for only 3-5% of cancers, but the mortality rate is disproportionately high. According to Jewel Samadder, MD, Assistant Professor of Internal Medicine at the University of Utah and colon cancer physician and researcher at HCI, cancer of unknown primary origin is the fourth most common cause of cancer-related death in men and women. Dr. Samadder says when the root of the cancer is unknown, it's impossible to use innovative therapies that target the source. Instead, patients are treated with generic chemotherapies that aren't as effective at eradicating the cancer. Cancers of unknown primary origin may move swiftly throughout the body, and as a result, the patient usually has little time left after a diagnosis.

Tahna Tyler knows this all too well. One year ago, after complaining of a severe pain in his left arm, her husband had a CT scan. Doctors found tumors in his shoulder area and lower back and he was admitted to HCI. Tumor after tumor was discovered inside his body, and Jack was diagnosed with cancer of unknown primary origin. Jack passed away just nine months after the first tumor was found. He was 54 years old. Tahna says Jack worried for the health of his three children, since some cancers are passed on genetically.

Those genetics are the focal point of Dr. Samadder's study. Using records from the Utah Population Database, he found a hereditary connection that not only put family members of patients with cancer of unknown primary origin at risk for CUP, but also at increased risk for four other types of cancer: colorectal, pancreas, lung, and non-Hodgkin lymphoma. Dr. Samadder hopes this research will help publicize the field of cancers of unknown primary origin so that more studies can be done and also alert family members of patients with CUP that they may be at increased risk so they can speak to their physician about appropriate screenings.

Right now, patients diagnosed with cancer of unknown primary origin live an average of three months after their diagnosis. Only 15% make it to one year. Dr. Samadder knows there's more work to be done so stories like Jack's become a thing of the past, but he is encouraged by these recent findings. He says, "I think that's why we work at places like HCI, to know there is hope."

For more information on cancer of unknown primary origin and the UPDB, visit

Huntsman Cancer Institute (HCI) is a National Cancer Institute (NCI)-Designated Comprehensive Cancer Center, which means it meets the highest standards for cancer research and receives support for its scientific endeavors. HCI is located on the campus of the University of Utah in Salt Lake City and is a part of the University of Utah Health Care system. HCI treats patients with all forms of cancer and operates several high-risk clinics that focus on melanoma and breast, colon, and pancreas cancers, among others. HCI also provides academic and clinical training for future physicians and researchers. For more information about HCI, please visit