Aunt Minnie reports PET superior to CT scan for evaluating vaginal carcinoma

 

7/12/2005

 

Positron emission tomography (PET) using F-18 fluorodeoxyglucose (FDG) is superior to computerized tomography (CT) in detecting primary vaginal carcinoma and its lymph node metastases, according to a report in the July 1st International Journal of Radiation Oncology, Biology, Physics.

"FDG-PET is the imaging study of choice for these patients and should be a routine part of their evaluation," Dr. Perry W. Grigsby from Washington University School of Medicine, St. Louis, Missouri, told Reuters Health.

 

Dr. Grigsby and colleagues compared FDG-PET and CT results from 23 consecutive women with primary carcinoma of the vagina. FDG-PET showed abnormal uptake in all 21 intact primary tumors and no abnormal vaginal uptake in two women with previous excision, the authors report, whereas CT detected intact primary tumor in only nine of the 21 patients (43%).

 

CT scan visualized abnormally enlarged groin lymph nodes (all of which were also palpable) in three patients and both groin and pelvic lymph nodes in one patient, the report indicates.

 

FDG-PET, on the other hand, revealed abnormal uptake in the groin lymph nodes in four patients, in the pelvic lymph nodes in two patients, and in both groin and pelvic lymph nodes in two patients.

 

Progression-free survival did not differ between women with PET-positive lymph nodes and women with PET-negative lymph nodes, the researchers note.

"The results of our study are comparable to those observed with other gynecologic malignancies," the investigators conclude. "FDG-PET appears to have similar utility in carcinoma of the vagina, detecting 100% of the primary tumors and identifying twice as many abnormal lymph nodes as found by CT."

 

"CMS (Centers for Medicaid and Medicare Services) should cover this test for these patients," Dr. Grigsby said.

Dr. Grigsby said he plans further studies to investigate the use of FDG-PET for the evaluation of responses to therapy, its ability to predict clinical responses to treatment, and its possible correlation with microarray analyses of biopsy specimens.