Surgical management: contemporary and future perspective
Despite the future probably lies in developing new drugs to target the
abovementioned molecular pathways, to prevent recurrent sinus surgery or
even avoid it, nowadays steroid therapy and surgery still play a
relevant role in the treatment strategy of CRS. Anti-inflammatory
therapies are at the forefront in the treatment of eosinophilic CRSwNP
(E-CRSwNP) and, above all, corticosteroids, both intranasal and systemic
(they contrast type 2 inflammation thus controlling both local and
associated systemic effects of the disease) [37]. However, chronic
and/or recurrent use of both systemic corticosteroids (particularly
frequent in patients with CRSwNP and concomitant severe asthma [38])
and topical corticosteroids is associated with a relevant increased risk
to develop adverse events (i.e.: type-2 diabetes, hypertension,
glaucoma, osteoporosis…) [37,39] that may have also a
dramatic burden in terms of health-care costs [40].
Along with steroids, sinonasal surgery improves nasal symptoms in
patients with CRSwNP. Especially in patients with aspirin intolerance,
allergic fungal rhinosinusitis (AFRS) and asthma, nasal polyposis is
histologically dominated by dense eosinophilic infiltration: in these
cases, a more aggressive surgical approach is required and is often
combined with extensive postoperative use of corticosteroids to preserve
good surgical results and prevent polyps regrowth [41]. Different
“versions” of endoscopic sinus surgery exist and technique has evolved
over time. Since 1984, Functional Endoscopic Sinus Surgery (FESS) has
become the world gold standard in the management of sinonasal
inflammatory disease unresponsive to medical therapy [41]. FESS, as
it was originally presented, currently leaves some interpretative
doubts. Based on its original principles, the aim of FESS is the
rehabilitation of a sinus ventilation by exposure of its natural ostium
without altering its profile, minimizing mucosal stripping and
preserving anatomical landmarks (such as the middle turbinate) [41].
This “limited” surgery is especially adequate for larger sinuses
(frontal and maxillary),that rarely require extensive manipulation. It
precisely means to clear ethmoidal clefts, reestablishing ventilation
and drainage of diseased large sinuses via their physiological
routes34: the frontal recess for frontal sinus
ventilation and the lateral wall of the middle meatus for maxillary
sinus ventilation. Little deviations from the FESS paradigm take place,
for example, when the maxillary sinus ostium is enlarged anteriorly
and/or posteriorly (to the nasal fontanelle areas), still resulting in a
window in its physiologic place. Over time, the concept of FESS has
developed further. According to EPOS 2020 steering group [1], “full
FESS” indicates sinus opening that includes anterior and posterior
ethmoidectomy, large middle meatal antrostomies, sphenoidotomy and
frontal opening (e.g. a Draf IIa procedure), still without damaging
important landmark as the middle turbinate and mucosa in general. This
is particularly applicable to compartmental sinusitis and CRSsNP, and it
can be applied to non-type 2 CRSwNP. The functionality criterion cannot
be respected in severely extensive CSRwNP and in conditions
characterized by type 2 inflammation, since limited surgery will not be
effective in the long run. As disease becomes more severe, wider
surgical resections turn out to be necessary: a large “ethmoidectomy
box” with wide lateral fenestration to the maxillary sinus, extended
upward to the frontal sinus and backward to the sphenoid. In many cases,
the steadiness of the middle turbinate is compromised by both the
destructive action of the disease and the extension of surgery. Being
systematic in the endoscopic approach (ESS) implementation and in
designing a targeted surgical treatment responds to the following needs:
to create a surgical bed as wide as possible to help control recurrence
with topical medications, to facilitate reintervention by simple polyps
debridement, to minimize post-surgical restenosis.
In spite of great advancements in the biologics field for very severe
and recurrent forms of polyposis, nowadays – and at least in the
initial phase of a larger diffusion of these new drugs – few patients
will have access to biological therapies. The first therapeutic attempt
in complicated and relapsing CRSwNP will certainly be surgery. In 2018,
a newly proposed approach (named “reboot approach” [42,43]) was
introduced in the surgical scenario of severe recalcitrant CRSwNP,
especially for cases who underwent multiple interventions. It aims to
restore a non-inflammatory state of the epithelium by entirely removing
the dysfunctional eosinophilic-infiltrated mucosa up to the periosteum
of nasal and paranasal cavities, partially sparing the mucosa of the
inferior conchas [42,43]. The procedure is accompanied by a Draf III
or at least Draf IIb frontal drainage. The rationale is that removal of
type 2 inflammatory environment might allow unaffected mucosa to grow
and re-epithelize sinuses walls, markedly decreasing the risk of
relapse.
An upcoming fascinating perspective could be represented by the
combination of surgery and biological therapy for E-CRSwNP. In such
manner, endoscopic surgery could be minimized to the true principles of
FESS, supported by the effects of post-operative administration of
targeted drugs.