Predictors of Aspiration Pneumonia in Head and Neck Cancer Patients Undergoing CRT

1. Predictors of Aspiration Pneumonia in Head and Neck Cancer Patients Undergoing CRT K. U. Hunter, F. Y. Feng, M. Schipper, T. Lyden, M. Haxer, D. Chepeha, A. Eisbruch

2. Materials and Methods • 72 patients with stage III-IV oropharyngeal cancer treated with CRT from 5/22/03-2/23/08 as part of UMCC 2-21 • Chemotherapy consisted of carboplatin (AUC=1) and paclitaxel (30mg/m2). • Radiation was delivered using IMRT with an attempt to spare OAR. Prescription doses: 70Gy/63Gy/59Gy.

3. Materials and Methods • VFs were performed pretreatment and at 3, 12, and 24 month intervals post-CRT. Patients who underwent nodal dissection also had a post-dissection VF. At each time point, multiple consistencies were tested: thin and thick liquids (5, 10, and 15 ml), pureed food, residue, cookie, and fruit. • Treatment-related toxicities were prospectively recorded.

4. Materials and Methods • EVENT = diagnosis of aspiration pneumonia by the patient’s physician on the basis of clinical symptoms of pneumonia (fever, fatigue, productive cough, etc.) with corresponding radiographic changes (infiltrates and/or consolidation on chest x-ray or thoracic CT interpreted as consistent with pneumonia by an attending radiologist).

5. *Analysis excluded 2pts that developed aspiraiton PNA prior to abnl VF.

6. Results • 16/72 pts developed aspiration pneumonia (1 additional case excluded b/c of EGD/anesthesia-related aspiration) • 10 pts required hospitalization • Median time from the start of radiation to the development aspiration pneumonia was 18.0 months (range 0.9-72 months).

7. Results • 13/16 aspiration PNA ptsshowed evidence of aspiration on VF. • Evidence of any VF-detected aspiration was predictive of aspiration PNA (p=0.02; sensitivity 80%, specificity 60%). • Evidence of aspiration on more than one VF study (p=0.023) and evidence of multiple aspiration during a study (p=0.001) improved the specificity of this test. ≥ 2 aspirations in any one swallow study was 72% specific, ≥ 6 aspirations during a swallow study was 90% specific.

8. Influence of VF Timepoint • Aspiration on the 12 month VF was the most predictive time point for aspiration PNA (p=0.002). Aspiration at 3 month VF was also sig (p=0.006).

9. Silent Aspriation • Silent aspiration or inefficient clearance of aspirate was noted on the VF studies in 10/16 aspiration PNA patients. This was not significantly associated with aspiration pneumonia (although 2pts that developed aspiration PNA prior to abnl VF study (and were excluded from analysis) did subsequently showed silent aspiration on VF).

10. Food Consistency • Each VF tested thin liquids (5, 10, and 15 ml), thick liquids (5, 10, and 15 ml), pureed food, residue, cookie, and fruit, • Thin liquids were the most commonly aspirated consistency (25/35 aspirators). • Thin liquids were predictive of the development of clinical aspiration pneumonia (p=0.005) and hospitalization for pneumonia (p=0.001). • Analysis of aspiration of thick liquids (p<0.02) and residue (p=0.02) were also predictive of clinical aspiration pneumonia. • Only 1/35 patients that aspirated did not aspirate either thin or thick liquids.

11. Other Factors • Nonsig factors: age, gender, AJCC stage, N-stage, history of smoking, current smoking (p=0.081), pack year history, pre-tx weight (p=0.061), weight change, and disease site. • Sig factors: T-stage (p=0.043) and age >70y/o (p=0.047)