Key words

IJNM

Indian Journal of Nuclear Medicine

0972-3919

Society of Nuclear Medicine, India

ijnm-22-4-051

RESEARCH ARTICLE

Whole Body PET/CT Study in Post Treatment Assesment of Nasopharyngeal Carcinoma

Shah

Pathak

Arora

Sharma

A R

Purandare

N C

Rangarajan

Bioimaging Unit, Tata Memorial Hospital, Parel, Mumbai, 400012

122007

224

Key wordsFDGPET-CTNasopharyngeal Carcinoma

Aims

To identify the usefulness of a whole body PET/CT study in post treatment cases of carcinoma of the nasopharynx.

Methods

A retrospective analysis of 55 post treatment (6–8 weeks to 2 years post concurrent chemotherapy and radiotherapy) cases of carcinoma of the nasopharynx referred to our department for evaluation of treatment response was done. Uptakes at the primary site, local nodal uptakes and abnormal uptakes elsewhere in the body were noted by a nuclear medicine physician. The simultaneously obtained contrast CT (CECT) images were analyzed by a radiologist blinded to the PET/CT report. Comparison of the contrast CT and PET/CT reports were done with respect to the primary and local nodes.

Results

There was a concordance of PET/CT and CECT findings at the primary site in 44 of the 55 patients, 22 patients showing no disease and 22 showing recurrence/residual disease. 11 (20%)of the patients showed discordance with 8 patients showing abnormality on the CT but no uptakes on PET/CT study. 3 patients showed residual/recurrence disease with no morphological abnormality on the CT images. 20 patients showed local nodal recurrence both on PET/CT and CECT. In 5 patients PET/CT identified local nodal involve-ment where CECT showed sub centimeter sized nodes which were normal by the size criteria. 10 CECT showed involved nodes in the neck while PET/CT did not reveal any corresponding abnormality. 16 patients had distant metastases 5 of these had distant nodal metastases only and 12 had metastases to distant organ in addition to distant nodal metastases.

Conclusion

29% (n =16) of the patients showed distant metastases. In addition to the above findings 20% of the patients benefited with additional information regarding the primary site in the nasopharynx. As regards the loco regional nodal staging, 14.28% of the patients were upstaged and 28.57% of the patients were down staged by PET/CT in comparison with conventional mode of investigation namely regional CECT.

Whole Body PET/CT Study in Post Treatment Assesment of Nasopharyngeal Carcinoma

Keywords