BACKGROUND: Inverted papilloma (IP) is a benign tumor characterized by epithelial proliferation, which has the potential for malignant transformation. However, the mechanisms driving this transformation are poorly defined. Matrix metalloproteinase-11 (MMP-11), a regulator of the tumor microenvironment that degrades extracellular matrix, is upregulated in IP with dysplasia. Here, we aim to investigate the role of MMP-11 in IP epithelial migration and invasion.
METHODS: Human IP and contralateral normal sinus mucosa (control) samples were obtained. IP-derived epithelial cultures and normal mucosa-derived epithelial cultures were grown in air‒liquid interface, followed by immunostaining to assess MMP-11 expression in IP. Migration and invasion assays were used to evaluate the role of an anti-MMP-11 antibody on IP and control epithelial cultures.
RESULTS: IP-derived cultures demonstrated strong MMP-11 expression compared to controls. Treatment with anti-MMP-11 blocking antibody significantly reduced epithelial migration only in IP-derived cells compared to non-treated IP cells, as seen by incomplete wound closure and reduced transepithelial resistance. In addition, inhibition of MMP-11 reduced IP epithelia\'s ability to invade through collagen-coated transwells, suggesting that MMP-11 plays a role in invasion.
CONCLUSIONS: We established an in vitro model to study IP-derived epithelial cells. MMP-11 is uniquely expressed in IP epithelial cultures compared to control epithelial cultures. Inhibition of MMP-11 limits IP epithelial migration and invasion to levels similar to that of normal sinus mucosa. MMP-11 does not appear to have a functional role in normal sinus epithelium, suggesting that MMP-11 has a role in malignant transformation of IP.

Objectives  Malignant tumors of the sinonasal cavities with extension to the frontal skull base are rare and challenging pathologies. Combined-approach surgery using a frontobasal craniotomy and endoscopic sinus surgery with reconstruction of the anterior skull base followed by adjuvant radiotherapy is a preferred treatment strategy in selected cases. Morbidity and mortality rates are high in this population. We aim to add our experience to the current literature. Design  We performed a retrospective cross-sectional single center study of the long-term clinical outcome in a tertiary university referral hospital in the Netherlands between 2010 and 2021. Descriptive statistics and frequency distributions were performed Participants  Patient, tumor, treatment, complications and survival characteristics of eighteen consecutive patients were extracted from the electronic health records. Main Outcome Measures  The primary outcome measures are progression free survival, overall survival and complication rate. Results  Eighteen consecutive patients were included with a mean age of 61 (SD ± 10) years (range 38-80); ten males and eight females. Gross total resection was achieved in 14 (77%) patients. Eleven (61%) patients underwent local radiotherapy, one (5%) chemotherapy and three (17%) a combination of both. Mean follow-up duration was 49 months (range 3 - 138). Three (17%) patients died in hospital due to post-operative complications. Six (33%) patients died during follow-up due to disease progression. Mean progression-free survival was 47 months (range 0 - 113). Conclusion  In conclusion, the overall survival was 50% for this group of patients with large sinonasal tumors. Progressive disease affects survival rate severely. Surgical complications were seen in five (28%) patients. Radiotherapy is associated with high complication rates. Radiation necrosis was a serious complication in two patients and could be treated with high dose steroids.

BACKGROUND: Sinonasal tumors represent a rare and heterogeneous group of rhinologic neoplasms. Even with advancements in surgical approaches, mortality rates of patients with sinonasal adenocarcinoma (SNAC) have not significantly improved and persistently high rates of recurrence in certain patients with inverted papilloma (IP) are seen. The use of 5-fluorouracil (5-FU) has been successfully described as an adjuvant treatment of SNAC and in the prevention of IP recurrence.
OBJECTIVE: This review aims to present the current evidence on the management of SNAC and IP with topical 5-FU.
METHODS: A three-author independent literature review was conducted to identify research involving the use of topical 5-FU for the treatment of SNAC and IP. A total of nine papers on the treatment of SNAC and IP were collected.
RESULTS: The earliest study looking at the combination of adjuvant low-dose radiation and topical 5-FU for adenocarcinoma of the ethmoid sinus showed a 5-year survival rate of 100%. A follow-up study evaluating a similar protocol reported adjusted disease-free survival at 2, 5, and 10 years of 96%, 87%, and 74%, respectively. Similar results have been demonstrated for adjuvant 5-FU use following endoscopic resection and have even been described in the novel setting of transcutaneous 5-FU delivery following frontal trephination. Topical 5-FU has also been described in the treatment of aggressive IP. The largest case series described the use of 5-FU for eighteen cases and demonstrated only a single recurrence.
CONCLUSIONS: The use of topical 5-FU currently represents an underutilized therapeutic modality within the treatment of rhinologic neoplasms. Available literature suggests that neoadjuvant use of topical 5-FU can improve survival and decrease recurrence for SNAC and IP. However, the small sample sizes prevent advocation for routine use in the general population and further research on 5-FU is necessary.

BACKGROUND: Nasal polyps and inverted papillomas often look similar. Clinically, it is difficult to distinguish the masses by endoscopic examination. Therefore, in this study, we aimed to develop a deep learning algorithm for computer-aided diagnosis of nasal endoscopic images, which may provide a more accurate clinical diagnosis before pathologic confirmation of the nasal masses.
METHODS: By performing deep learning of nasal endoscope images, we evaluated our computer-aided diagnosis system\'s assessment ability for nasal polyps and inverted papilloma and the feasibility of their clinical application. We used curriculum learning pre-trained with patches of nasal endoscopic images and full-sized images. The proposed model\'s performance for classifying nasal polyps, inverted papilloma, and normal tissue was analyzed using five-fold cross-validation.
RESULTS: The normal scores for our best-performing network were 0.9520 for recall, 0.7900 for precision, 0.8648 for F1-score, 0.97 for the area under the curve, and 0.8273 for accuracy. For nasal polyps, the best performance was 0.8162, 0.8496, 0.8409, 0.89, and 0.8273, respectively, for recall, precision, F1-score, area under the curve, and accuracy. Finally, for inverted papilloma, the best performance was obtained for recall, precision, F1-score, area under the curve, and accuracy values of 0.5172, 0.8125, 0.6122, 0.83, and 0.8273, respectively.
CONCLUSIONS: Although there were some misclassifications, the results of gradient-weighted class activation mapping were generally consistent with the areas under the curve determined by otolaryngologists. These results suggest that the convolutional neural network is highly reliable in resolving lesion locations in nasal endoscopic images.

Background: The goal of this research was to confirm whether preoperative serum squamous cell carcinoma antigen (SCCA)-1 and -2 levels are useful diagnostic markers for sinonasal inverted papilloma (IP) in a prospective study. Methods: Participants were 102 patients who underwent consecutive endoscopic sinus surgery: 18 with IP, two with other types of papilloma, 77 with chronic rhinosinusitis, four with sinonasal cancer, and one with hemangioma. SCCA-1 and SCCA-2 were measured preoperatively by an automatic chemiluminescence immunoassay and an enzyme-linked immunosorbent assay, respectively. Results: SCCA-1 and SCCA-2 values were significantly correlated (r = 0.603, p < 0.001). Receiver operating characteristic analysis for differentiating papilloma (IP and other types of papilloma) from other diseases yielded an area under the curve of 0.860, with a Youden index of 1.75. Combined with SCCA-2 analysis, the detection system had a sensitivity and specificity of 0.65 and 0.98, respectively. While our study did not find a strong link between SCCA levels and skin or lung diseases, smoking status may influence SCCA levels in IP patients (p = 0.035). We recommend a cutoff value of 1.8 ng/mL for SCCA-1 in IP diagnosis. Conclusions: SCCA-1 and SCCA-2 when combined with imaging and pathology hold promise for enhancing the preoperative detection of IP, which would be a valuable contribution to clinical practice.

Inverted papilloma is a tumor found involving the nasal cavity and paranasal sinuses. They are not cancerous but can be locally aggressive. They are most commonly seen involving the lateral wall of nose and maxillary sinus. When the tumor involves the frontal sinus and sphenoid sinus or the post ethmoid cells it presents a surgical challenge. Inverted papilloma almost always occur unilateraly and affect mainly the maxillary sinus. Inverted papilloma arising from the sphenoid and frontal sinuses are rare. Here we present two cases; one involving a 60 year man, with inverted papilloma originating from the frontal sinus and another case where it originated from the sphenoid sinus anterior wall and posterior ethmoidalcell (Onodi cell) and was resected endoscopically.

Diagnosis of maxillary sinus pathologies is challenging. Herewith we describe the clinicopathological features in isolated maxillary sinus lesions in tertiary care hospital in Goa, India. The retrospective study included patients treated between 2017 and 2022, of all age groups and gender, who underwent either a biopsy or surgery, providing a histopathological diagnosis. Of the 117 pathologies, 88 (75.2%) were non-neoplastic. The overall frequency of pathologies were polyp in 40.2%, fungal lesions (18.8%), malignancy (13.7%), chronic rhinosinusitis (11.9%) and inverted papilloma (10.3%). There were 71 men (60.7%) and 46 women (39.3%). There were 10 patients (8.5%) below 20 years of age, of which 8 patients (80%) had non-neoplastic pathology. Common comorbidities were diabetes and hypertension, while symptoms were nasal blockage (75.2%), nasal discharge (47%) and ocular redness (16.2%). Each pathology was evaluated for demography, side of lesion, comorbidity, and symptoms. Most isolated maxillary sinus pathologies were benign lesions. However, a strong clinical suspicion and histopathological confirmation is needed for all lesions in all age groups due to a risk of malignancy.

OBJECTIVE: This large retrospective, single-center, follow-up study investigated the endoscopic prelacrimal recess approach (PLRA) for treating maxillary sinus inverted papilloma (MSIP).
METHODS: Between January 2007 and November 2022, patients with MSIP treated with PLRA were enrolled. Data on clinical manifestations, imaging, and surgical procedures were collected. The visual analog scale (VAS) scores for maxillofacial numbness and nasal symptoms and the SNOT-22 nasal symptom scores were statistically analyzed.
RESULTS: Of 122 patients (68 males and 54 females) enrolled in the study, with a mean age of 50.75 ± 12.84 years (26-80 years), 111 patients underwent PLRA, nine underwent modified PLRA, one converted to an endoscopic medial maxillectomy (EMM), and one to an endoscopic modified Denker\'s approach. The average follow-up was 86.60 (13-192) months, the recurrence rate was 3.28%, and 29 patients (23.77%) complained of maxillofacial numbness one month postoperatively, which disappeared in most cases one year after surgery. Five patients (4.10%) experienced mild numbness at the end of the follow-up period. Maxillary sinus ostium contracture or atresia occurred in two cases (1.64%). After surgery, the VAS nasal symptom scores improved significantly (P < 0.001). SNOT-22 indicated that the most common postoperative symptom was thick nasal discharge.
CONCLUSIONS: PLRA is a flexible first-choice surgical treatment for maxillary sinus inverted papilloma and can be modified according to the extent of the lesion, the surgeon\'s experience and technique, and surgical instruments. That can help achieve complete resection and reduce recurrence and surgical complications. Upper teeth numbness, the most common postoperative complication, tends to disappear after 1 year.

UNASSIGNED: This study aimed to evaluate the characteristics and treatment outcomes of inverted papillomas involving the frontal sinus.
UNASSIGNED: Patients treated for inverted papilloma involving the frontal sinus between 2003 and 2020 were reviewed. Tumors were classified based on their extent (Extent 1: partially encroaching on the frontal sinus; Extent 2: completely filling the frontal sinus; Extent 3: eroding bony borders beyond the frontal sinus) and site of origin (Origin 1: originating outside the frontal sinus and prolapsing into the frontal sinus; Origin 2: originating from the frontal sinus walls medial to the vertical plane of the lamina papyracea; Origin 3: originating from the frontal sinus walls lateral to the vertical plane of the lamina papyracea). Treatment outcomes including tumor recurrence and patency of the frontal recess were analyzed according to tumor characteristics and surgical treatment modalities.
UNASSIGNED: A total of 49 surgical cases were analyzed. Extent 1 were the most common type (n = 27), followed by Extent 2 (n = 15), and Extent 3 (n = 7). The most common sites of origin were Origin 1 (n = 23), followed by Origin 2 (n = 15), and Origin 3 (n = 11). Overall, there were nine recurrences (18.4%). Recurrence was not associated with tumor extent, whereas tumor origin, particularly Origin 3 was associated with higher recurrence; 1/23 (4.3%) for Origin 1, 3/15 (20.0%) for Origin 2, and 5/11 (45.5%) for Origin 3 (Log-rank p < .001). Draf III frontal sinusotomy was associated with in the highest patency rate (84.6%) during the follow-up.
UNASSIGNED: The recurrence rate of frontal sinus inverted papilloma depends on tumor origin rather than the extent of the tumor. In particular, lesions originating from the frontal sinus lateral to the lamina papyracea recur frequently. Draf III frontal sinusotomy can achieve patent frontal recess allowing active surveillance.
UNASSIGNED: IV.

BACKGROUND: Diseases of the nose and paranasal sinuses have a significant impact on the patient\'s functional and structural aspects. They affect all age groups and both sexes. Due to its proximity to vital structures, diseases of the nose and paranasal sinuses sometimes lead to very grave prognoses.
METHODS: This was a retrospective study done in one of central India\'s largest tertiary care centers. We studied 227 cases of sinonasal masses in both the non-neoplastic and neoplastic categories. Clinicopathological characteristics of masses were analyzed with the help of clinical and imaging findings and subsequently confirmed by tissue diagnosis.
RESULTS: The mean age of presentation was 45.5 years, with a male-to-female ratio of 1.25:1. Most of our patients were from lower-middle socioeconomic groups with educational qualifications below the 10th standard. Nasal obstruction was the most common symptom. A computed tomography scan was the preferred radiological investigation. Sinonasal undifferentiated carcinoma was the most common variant of malignancy, with a total number of six out of 22 (27%).
CONCLUSIONS: The evaluation of sinonasal masses should be carried out systematically and meticulously. Since the initial presentation of most of the diseases of the nose and paranasal sinuses is the same, a proper clinical, radiological, and tissue diagnosis should be carried out to avoid causing malignant lesions.