Sinonasal inverting papilloma: who is at risk of recurrence?
Reviewed by Suki Ahluwalia

This study from a tertiary sinus surgery unit, describes some useful information in the follow-up of sinonasal inverted papilloma patients - in particular those likely to recur - and discusses the optimal staging systems to use to attempt to predict recurrence. It is a retrospective study looking at patients with SNIP over an eight-year period, both primary and revision cases. A total of 74 cases were reviewed and each was staged using all of the available staging systems retrospectively by a single blinded author, based on CT findings. All operations were undertaken by the senior author and, after removal of the tumour, the area of attachment to the sinus was polished with a diamond burr. Primary cases amounted to 52 and there were 22 revision cases, defined as cases referred from other centres with recurrence, the mean age at the time of surgery was 59 years and 70% were male. Mean follow-up was 42 months: 54% of tumours were in the maxillary sinus, 15% ethmoid, 12% sphenoid, 14% frontal sinus and 5% septum. Sixteen patients had a recurrence, primary cases (21%) and for revision cases (23%) which commonly was within the first year. However, the mean time to recurrence was 24 months in primary and 15 months in revision cases. Recurrence rates according to origin were maxillary 28%, ethmoid 18%, sphenoid 11%, frontal 20% and 0% from the septum. No association between smoking history and recurrence was found. Highest rates of recurrence were found in the age group 20-39 years. Patients were all staged using the Krouse, Okiwawa, Cannady, Han and Kamel staging systems. Authors found that the Han and Cannady staging systems better identified those at risk of recurrence rather than systems which categorised patients due to the sinus origin of their tumour. Overall, an interesting read which enforces the need for regular follow-up in this group of SNIP patients with a risk of recurrence which seems to be higher in younger patients and within the first two years of surgery. 

Sinonasal inverted papilloma recurrence rates and evaluation of current staging systems.
Mak W, Webb D, Al-Salihi S, et al.
RHINOLOGY
2018;56(4)407-14.