THURSDAY, Jan. 14 (HealthDay News) -- Whole-body positron emission tomography-computed tomography (PET-CT) can detect certain small cancers early in some patients in whom standard evaluation has failed to detect disease, making earlier treatment possible, according to a study published online Jan. 11 in the Archives of Neurology.
Andrew McKeon, of the Mayo Clinic in Rochester, Minn., and colleagues performed PET-CT on 56 patients clinically suspected of having paraneoplastic neurologic disorders who had had negative standard evaluations for cancer, including CT scans. The primary outcome was rate of cancer detection using PET-CT.
The researchers found that the PET-CT screening found abnormalities suggesting cancer in 22 of 56 patients, while cancer was confirmed histologically in 10 of 56 patients. The confirmed cancers included three lung carcinomas, three solitary lymph nodes with unknown primary cancer, two thyroid papillary cell carcinomas, one tonsil squamous cell carcinoma, and one colon adenocarcinoma. Detection of a neuronal nuclear or cytoplasmic paraneoplastic autoantibody was associated with a successful discovery of cancer using PET-CT. Early detection of cancer with PET-CT facilitated early treatment, and in median 11 months follow-up, cancer remission occurred in seven patients and improvements of neurologic symptoms occurred in five patients.
"In a paraneoplastic neurologic context, PET-CT improves the detection of cancers when other screening test results are negative, particularly in the setting of seropositivity for a neuronal nuclear or cytoplasmic autoantibody marker of cancer," the authors write.
One of the study authors stands to receive royalties for commercial assays in development to detect aquaporin-4-specific autoantibodies.