Carcinoma of unknown primary
What is head and neck cancer of unknown primary site?
Head and neck cancer of unknown primary site usually presents as a lump in the neck, which is a sign that the cancer has spread to one or several of the lymph nodes in the neck. The origin of the metastasis (cancer spreading from one area to another) is not apparent because often there are no other associated symptoms other than the neck mass. The goal of the head and neck surgeon is to find and treat the location of the cancer itself and the metastasis (neck lymph nodes).
What are the symptoms of head and neck cancer of unknown primary site?
Patients often have no symptoms other than a neck mass. Difficulty swallowing, throat pain, or ear pain sometimes provide clues regarding the site of origin of the primary cancer.
How is head and neck cancer of unknown primary site diagnosed?
A biopsy is performed of the neck mass to determine whether it is cancerous. Further evaluation is critical to try and identify the exact location of the cancer origin. After a careful examination and endoscopy of the mouth and throat, your doctor will begin to search for the origin of the metastasis by using imaging technology (MRI, CT scan, PET/ CT scan). If a patient has a history of skin cancers removed or burned off in the past, a dermatologic evaluation may be necessary.
If imaging doesn’t clearly show the origin of the metastasis, patients will undergo examination and biopsies under general anesthesia. These biopsies are done to sample the most likely areas in the mouth or throat in which the cancer of origin may reside.
How is head and neck cancer of unknown primary site treated?
The first and most important step of treatment is to find the location where the cancer originated, as this will inform treatment planning.
If the cancer location is successfully discovered, treatment will be initiated appropriate to the specific origin of the tumor.
However, if no origin is discovered after imaging and more thorough examinations and biopsies, a treatment plan will be developed using the information gathered from the neck biopsies. HPV, EBV, and p16 testing will inform these decisions. Patients in this situation may undergo surgery or radiation therapy on the area where the neck mass presented and the areas where the cancer most likely originated. They may benefit from chemotherapy as determined by discussion with the medical oncologists as part of the multi-specialty oncology team.
Treatment recommendations are carefully discussed among head and neck surgeons, radiation oncologists and medical oncologists.