Findings and analysis of the results
Our most important findings were that patients who had undergone surgery of benign sinonasal tumours appear to have a very mildly impaired quality of life (median of 12 on the SNOT-22 score). Healthy people score an average of 9.3 points on the SNOT-22 [
9], while patients with chronic rhinosinusitis have an average of 51.8 [
10]. The difference of 3 points is measurable but of doubtful clinical significance; it has been shown that a change of less than 9 points cannot be perceived as a real improvement or impairment by the patient [
11].
A study that used SNOT-20 to assess the quality of life of patients after endoscopic removal of tumours was published by Harrow and co-authors [
12]. Although the postoperative mean SNOT-20 score for benign tumours was 11.6 in their study, grossly equivalent to 13 in our scale, comparisons are difficult, as their study includes skull base tumours with significantly less follow-up and other kinds of benign sinonasal tumours which were not included in our study. In a way, our study is complementary to the study by Harrow, as it shows that quality of life continues to improve with time—our better reported quality of life may reflect the fact that their follow-up was 6 months, while ours was several years.
SNOT-22 questionnaires are also used for other sinonasal surgery. In all studies found, the SNOT-22 scores are higher than 9, which means there is an impaired quality of life after the operation; this confirms our findings. Buckland and co-authors report that the average postoperative SNOT-22 score in patients having undergone successful septal surgery is 19.3 after approximately 3 months [
13]. Ransom and co-authors report an average SNOT-22 score of 14 a year after complete endoscopic resection of anterior skull base neoplasms [
14]. The preoperative mean SNOT-22 score in their patient group was 47.
In our patient group, there is after 5 years a very minor, barely measurable and likely not of any clinical significance, quality of life impairment in patients who undergo an endoscopic excision of benign tumours.
The most frequent symptom reported in our patient group was the need to blow the nose, although the median score was reported as 1. This is likely reflective of a larger sinonasal cavity. Other frequent symptoms were waking up at night, postnasal discharge, thick nasal discharge and sneezing.
The most frequently reported preoperative symptoms were nasal obstruction and rhinorrhoea.
In studies about inverted papilloma and chronic rhinosinusitis, the most frequent symptom was nasal obstruction, which was confirmed in our study [
4,
15,
16]. No postoperative patient group comparable to ours has been studied using the SNOT-22.
After analysis, it appeared we did not have to correct the results for the outliers. There are two patients scoring more than 60 on the SNOT-22 score, the result of unrelated co-morbidity (malignancy and depression). When these patients are removed from the database, the median becomes 11, suggesting that the results are not majorly influenced by those outliers.
Furthermore, the results did not have to be corrected for the extent of the endoscopic surgery, since there was no significant difference between the SNOT-22 scores in the different groups.
Strengths and limitations
The strengths of our study include that the patients were approached personally and at different times of the day, to avoid just reaching the patients who were not working or not able to work. The long follow-up of the patients was a strength of the study, which is longer than current studies have investigated. One of the limitations of our research is that the patient group is small (27 patients) and that we could not reach 100 % of the patients. The majority of patients who did not respond appeared to have moved, which meant they could not be contacted by telephone or through mail. In a few, there may be nonresponse bias; patients without any symptoms, or, on the contrary, patients with major complaints and plenty of symptoms, may not have answered; however, an analysis of the non-responders did not show any obvious difference in age or preoperative symptoms. Furthermore, we do not have a preoperative SNOT-22 score to compare, as we are restricted by the retrospective nature of our study. However, we have reported preoperative symptoms, which give an indication for the reason of consulting the ENT-specialist.