3 RESULTS
The mean age of the 41 patients was 57.7 ± 9.9 years and the male to female ratio was 34:7. The most common subsite was the palatine tonsil (30 cases), followed by the base of tongue (9 cases). Pathologic testing confirmed that 38 (92.7%) were squamous cell carcinomas and 3 were basaloid squamous cell carcinoma. Nineteen out of 26 patients (73.1%) were p16 positive. According to the 8th version of the American-Joint Cancer Classification (AJCC) staging system,22 the number of T1/T2/T3/T4 patients was 17/23/1/0, the number of N0/N1/N2 patients was 12/19/10 and the number of stage I/II/III/IV patients was 7/3/19/12. Forty patients (97.6%) underwent neck dissection concomitant with TORS. Tracheostomy was performed on six (14.6%) TORS patients. The mean time of console work for TORS was 94.7 ± 41.5 min. There were 1 case of minor hematoma and 6 cases of seroma in the neck. None of the cases was converted to conventional surgery. Thirty-six patients (87.8%) received adjuvant radiation or chemoradiation therapy (Table 2).
We defined the abnormal cut-off values for tongue motility, maximal phonation time, verbal diadochokinesis, articulation tests, and reading speed as two standard deviations above or below the value of normal subjects (Table 3).
The mean tongue motility score was 15.5 ± 1.2 (range, 13 – 17) in this study. Only 3 patients had abnormal tongue motility scores below the cut-off value defined in the study (below 14.58). The mean maximum phonation time was 17.8 ± 6.9 sec (range, 9.2 – 35.7) in this study. No patient was lower than the abnormal cut-off value.
The mean articulation score was 5.9 ± 0.3 (range, 5 – 6) in this study. No patient showed an abnormal cut-off value score (lower than 4.79). The mean verbal diadochokinesis score (sum of regularity and accuracy) was 25.1 ± 2.1 in this study, which was higher than the abnormal reference value (< 21.83). The mean reading speed was 11.9 ± 2.3 sec (range, 9.1 – 15.8) in this study. All patients were below the abnormal cut-off value score (higher than 18.2 sec).19
In the subgroup analysis of articulation and speech outcomes according to primary site and T classification, there were no significant differences between the tonsil and base of tongue and between T1 and T2 primary cancers (Table 4).
MBS was performed in 32 patients. Generally, the results of MBS were favorable in all patients. However, in the oral stage, mild piecemeal deglutition was noted in 3 patients, premature bolus loss in 8 patients, and presence of mouth residue in 3 patients. Reduced laryngeal elevation and epiglottic closure and repeated swallowing were seen in only 2 patients in the pharyngeal stage. In the esophageal stage, delayed passage was noted in 7 patients, opening of pharyngoesophageal segment in 4 patients, and gastroesophageal reflux in 4 patients (Table 5). None of the patients needed nasogastric or PEG tubes before adjuvant therapy. However, one patient (2.4%) with T2 tonsil cancer required permanent PEG tube placement after chemoradiation therapy. No patients required permanent tracheostomy.