Source: Office of Medical Science
Written by: Office of Medical Science
Edited by: Wang Dongmei

Professor Hai-Qiang Mai’s research team from Sun Yat-sen University Cancer Center, have found that PET/CT detects more distant metastases than conventional staging in patients with nasopharyngeal carcinoma (NPC), and the largest benefit in terms of cost and patient management was observed in the subgroup with N2-3 disease and EBV DNA ≥4000 copies/ml. This study was published in the Journal of Clinical Oncology (SCI IF 18.038) on August 10, 2013.

Conventional work-up (CWU), including chest X-ray, abdominal ultrasound, and skeletal scintigraphy is still widely used in endemic areas, because it is available and affordable. However, PET/CT is costly, up to ¥10,000 per patient, time-consuming and impractical to use for all NPC patients. The doctors as well as the NPC patients are still uncertain how much benefit is obtained with the addition of PET/CT to the conventional work-up (CWU). Given that the clinical issue in question, professor Mai’s research team launched this prospective study since 2007 and a total of 583 patients were recruited during the past 4 years. The research founded that PET/CT detects more distant metastases than conventional staging in patients with NPC. Combining the N stage and pretreatment EBV DNA level, the whole NPC population was divided into three different risk groups: very low risk ((N0-1 with EBV DNA<4000 copies/ml), low risk (n0-1 with ebv dna ≥4000 copies/ml and n2-3 with ebv dna<4000 copies/ml), and intermediate risk (n2-3 disease with ebv dna ≥4000 copies/ml). pet/ct was not superior to cwu for detecting distant metastases in very low risk patients, but was superior for the low-risk patients and intermediate-risk patients. the corresponding patient management changes based on pet/ct were 2.9%, 6.3% and 16.5%, respectively. the costs per true-positive case detected by pet/ct among these groups were ¥324,138(≈$47,458), ¥96,907(≈$14,188), and ¥34,182(≈$5,005), respectively. based on this findings, the investigators recommend a cwu for the very low-risk population, cwu or pet/ct for the low-risk population, and pet/ct for the intermediate-risk npc population.

Professor Mark N. Levine, associated editor of the Journal of Clinical Oncology, made a high appraisal of this research in the editorial and considered that the investigator wisely combining the pretreatment EBVDNA level, selected application of a PET/CT test based on risk, guiding the clinical application of PET/CT test of NPC patients. Professor Levine also thought that the insights provided by their study can also be generalized to other countries that are struggling with the burden of health costs related to new technologies.

The research was supported by grants from the Fundamental Research Funds for the Central Universities and Sun Yat-sen University 5010 Project.