The DEBATE Study "DEvelopment of Endotype-based Biomarkers for the Monitoring of Greek pATiEnts With CRSwNP"

Cytokine/chemokine analysis of the fresh extracted nasal tissue following first ESS will be performed by Luminex and ELISA analysis

Immunophenotypic analysis by spectral flow cytometry of all main immune cell types, as well as detailed characterization of all T cell subsets will be performed in the fresh samples.

Eosinophil and neutrophil cell counts will be recorded, as per the EPOS 2020, eosinophilia is defined as >10 eosinophils/hpf.

Tissue morphology and potential tissue destruction and nasal epithelium remodeling by standard histology staining (e.g. hematoxylin and eosin, Periodic Acid-Schiff (PAS), and Sirius Red staining) will be assessed in stored nasal polyp tissue paraffin sections or paraffin blocks.

Demographics at study entry/screening (age, sex, ethnicity, smoking status, cigarettes/day/year, alcohol status (units/week), body measurements (BMI kg/m2), employment status, educational level, residence area) will be recorded

Patients' medical history, including the date of first and severe CRSwNP diagnosis, comorbidities, and disease management [use (yes/no) of saline, systemic/local glucocorticoids, biologics, antibiotics], will be reported at the time of enrolment and during 24 months after first ESS.

Time to first ESS from CRSwNP diagnosis and from severe CRSwNP diagnosis will be assessed

The 22-item Sinonasal Outcome Test (SNOT-22), which is a health-related quality of life (HRQoL) evaluation with each item scored on a Likert scale ranging from 0 "No problem" to 5 "Problem as bad as it can be".

The Nasal Polyposis Symptom Diary (NPSD), which is a short patient-reported outcome (PRO) tool comprising 11 items (8 symptom-specific, 2 symptom-impact, and 1 optional medication-compliance). The Total Symptom Score (TSS) is a summary of the first 8 symptom-specific items, scored on a 4-point scale [0-none, 1-mild, 2-moderate, 3-severe], with a resulting score from 0 to 24

The Asthma Control Test (ACT), a patient-based tool for identifying patients with poorly controlled asthma that includes 5 items assessing the frequency of shortness of breath and general asthma symptoms, use of rescue medications, the effect of asthma on daily functioning, and overall self-assessment of asthma control. The ACT responses for each of the items are summed to yield a score ranging from 5 (poor control of asthma) to 25 (complete control of asthma), with higher scores reflecting greater asthma control.

NPS is a physician-reported tool that grades the extent/severity of nasal polyps based on evaluation by nasal endoscopy. Each nostril is scored on a scale of 0 - "No nasal polyps" to 4 - "Large nasal polyps causing complete obstruction of the inferior nasal cavity", with the total score being the sum of left and right nostril scores (range: 0-8).

The Lund-Mackay (LM) CT score that evaluates sinus opacification on CT scans. This score ranges from 0 -"complete lucency of all sinuses" to 24 - "complete opacity of all sinuses"

Cytokine/chemokine analysis of blood samples following first ESS will be performed by Luminex and ELISA analysis

Immunophenotypic analysis by spectral flow cytometry of all main immune cell types, as well as detailed characterization of all T cell subsets will be performed in the fresh samples.

Serum immunoglobulin levels [total IgE, specific IgE to staphylococcal enterotoxins (SE-IgE)]

Differential WBC count (incl. absolute count) will be recorded

RBC count will be recorded

The number of CRSwNP recurrences along with the date(s) of recurrence(s) will be recorded in the eCRF by the investigator at 24 months following first ESS for CRSwNP patients (including retrospective CRSwNP patients, if data are available). The time to relapse during the 24-month follow-up will be also estimated.

Endotypes of CRSsNP patients who have performed first ESS in the period between 2012 and enrolment (retrospective patients) will be determined based on cytokine/chemokine analysis of frozen extracted nasal tissue from ESS, including Fractalkine, GM-CSF, IFNγ, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, (p70), IL-13, IL-17A, IL-21, IL-23, ITAC, MIP-1α, MIP-1β, MIP-3α, TNF-α, TSLP, IL-9, IL-33, IL-17E/IL-25, TGFb1, IL-22

Eosinophil and neutrophil cell counts will be recorded. As per the EPOS 2020, eosinophilia is defined as >10 eosinophils/hpf

tissue morphology and potential nasal tissue destruction and remodeling by standard histology staining (e.g. Hematoxylin and eosin, Periodic acid-Schiff (PAS), and Sirius Red staining) will be assessed in stored nasal polyp tissue paraffin sections or paraffin blocks. Depending on the nature of tissue pathology, further immunohistochemical analysis will be performed with the use of specific antibodies, such as markers for epithelial barrier integrity (e.g. E-cadherin or Cytokeratin), tissue remodeling (e.g. MMP-9) or chronic damage monitored by fibrosis (e.g. α-SMA or collagen)