Swallowing After Primary TORS and Unilateral or Bilateral Radiation for Low- to Intermediate-Risk Tonsil Cancer

Abstract

Objective: The primary course of treatment for patients with low- to intermediate-risk tonsil cancer has evolved with a shift toward primary transoral robotic surgery (TORS) or radiation therapy (RT). While favorable outcomes have been reported after deintensification via unilateral TORS or RT (uniRT), comparisons of functional outcomes between these treatments are lacking. We compared clinical outcomes (Dynamic Imaging Grade of Swallowing Toxicity [DIGEST] and feeding tube [FT]) and patient-reported swallowing outcomes (MD Anderson Dysphagia Inventory [MDADI]) based on primary treatment strategy: TORS, uniRT, or bilateral RT (biRT).

Study design: Secondary analysis of prospective cohort.

Setting: Single institution.

Methods: The study sample comprised 135 patients with HPV/p16+ T1-T3, N0-2b (American Joint Committee on Cancer, seventh edition), N0-1 (eighth edition) squamous cell carcinoma of the tonsil were sampled from a prospective registry. Modified barium swallow studies graded per DIGEST, FT placement and duration, and MDADI were collected.

Results: Baseline DIGEST grade significantly differed among treatment groups, with higher dysphagia prevalence in the TORS group (34%) vs the biRT group (12%, P = .04). No significant group differences were found in DIGEST grade or dysphagia prevalence at subacute and longitudinal time points (P = .41). Mean MDADI scores were similar among groups at baseline (TORS, 92; uniRT, 93; biRT, 93; P = .90), subacute (TORS, 83; uniRT, 88; biRT, 82; P = .38) and late time points (TORS, 86; uniRT, 86; biRT, 87; P = .99). FT placement and duration significantly differed among primary treatment groups (FT [median days]: TORS, 89% [3]; uniRT, 8% [82]; biRT, 37% [104]; P < .001).

Conclusion: While TORS and uniRT offer optimal functional outcomes related to dysphagia, results suggest that no measurable clinician-graded or patient-reported differences in swallow outcomes exist among these primary treatment strategies and biRT. Aside from baseline differences that drive treatment selection, differences in FT rate and duration by primary treatment strategy likely reflect diverse toxicities beyond dysphagia.

Keywords: dysphagia; head and neck cancer; radiation; surgery; unilateral.

Figure 1.

Proportion of DIGEST grade by primary treatment strategy in low- to intermediate-risk tonsil squamous cell carcinoma (N = 135): (a) baseline, (b) subacute, and (c) long term. biRT, bilateral radiation therapy; DIGEST, Dynamic Imaging Grade of Swallowing Toxicity; MBS, modified barium swallow; TORS, transoral robotic surgery; uniRT, unilateral radiation therapy.

Figure 2.

Proportion of MDADI by primary treatment strategy in low- to intermediate-risk tonsil squamous cell carcinoma (N = 135): (a) baseline, (b) subacute, and (c) long term. biRT, bilateral radiation therapy; MDADI, MD Anderson Dysphagia Inventory; TORS, transoral robotic surgery; uniRT, unilateral radiation therapy.

Figure 3.

Time-series plots detailing duration of (a) any feeding tube and (b) PEG tube only (in days) by primary treatment strategy in low-to intermediate-risk tonsil squamous cell carcinoma (N = 135). PEG, percutaneous endoscopic gastrostomy; TORS, transoral robotic surgery.

Figure 4.

Proportion of DIGEST grade by multimodality treatment in low- to intermediate-risk tonsil squamous cell carcinoma (N = 135): (a) subacute and (b) long term. CRT, chemoradiation therapy; DIGEST, Dynamic Imaging Grade of Swallowing Toxicity; MBS, modified barium swallow; RT, radiation therapy; TORS, transoral robotic surgery.