Early prediction of response to chemoradiotherapy for head and neck cancer: reliability of restaging with combined positron emission tomography and computed tomography.
OBJECTIVE
To assess the role of combined positron emission tomography and computed tomography (PET-CT) in predicting early treatment response at the primary site and in the neck after chemoradiotherapy (CRT) for advanced squamous cell carcinoma of the head and neck (SCCHN).


METHODS
Retrospective analysis with a median follow-up of 24 months.


METHODS
Academic, tertiary referral center.


METHODS
Thirty-one patients who were treated with concomitant intra-arterial CRT underwent PET-CT 6 to 8 weeks after the completion of treatment. Patients with findings on the physical examination, CT, or PET-CT indicative of persistent disease underwent appropriate surgical intervention for pathological assessment. Patients with a complete clinical response were observed with routine follow-up physical examination for disease recurrence. No evidence of disease at least 6 months after the completion of PET-CT was considered confirmation of complete clinical response.


METHODS
Presence or absence of residual or recurrent disease during the follow-up period was used to calculate the sensitivity, specificity, and positive and negative predictive values of PET-CT for the primary site and the neck.


RESULTS
Assessment of tumor response at the primary site with PET-CT had a sensitivity, specificity, and positive and negative predictive values of 83%, 54%, 31%, and 92%, respectively. In patients with pretreatment N1 to N3 disease, the sensitivity, specificity, and positive and negative predictive values of posttreatment PET-CT were 75%, more than 94%, more than 75%, and 94%, respectively, and the specificity and negative predictive value for patients with pretreatment N0 disease in the neck were 92% and more than 92%, respectively.


CONCLUSIONS
Negative PET-CT findings accurately determine early disease response at the primary site and in the neck. False-positive findings are common at the primary site. Patients with a negative PET-CT finding after the completion of intra-arterial CRT do not require surgical intervention.
Malone
James P
JP
Department of Surgery, Southern Illinois School of Medicine, Springfield, IL 62794-9649, USA. jmalone@siumed.edu
Gerberi
Michael A T
MA
Vasireddy
Syam
S
Hughes
Larry F
LF
Rao
Krishna
K
Shevlin
Bruce
B
Kuhn
Matthew
M
Collette
Dean
D
Tennenhouse
Joel
J
Robbins
K Thomas
KT
D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000188:drug therapy / Q000532:radiotherapy*; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D009367:Neoplasm Staging / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*
D000970:Antineoplastic Agents