Correlation of intensity-modulated radiation therapy at a specific radiation dose with the prognosis of nasal mucous damage after radiotherapy.

Objective of the present study was to investigate the tolerant radiation dose of nasal mucosa by observing and analyzing patients who received intensity-modulated radiation therapy (IMRT). Patients with nasopharyngeal carcinoma (N = 66) were selected for this study. The modified saccharin assay, endoscopy test, magnetic resonance imaging, and sino-nasal outcome test-20 (SNOT-20) survey were performed for the patients before and at 0 (T0), 3 (T1), 6 (T2), and 12 (T3) months after radiotherapy. The threshold doses of IMRT before radiotherapy and at T0, T1, T2, and T3 were determined as, respectively, 37 Gy, 37 Gy, 39 Gy, and 37 Gy for the saccharin test; 38 Gy, 37 Gy, 40 Gy, and 38 Gy for the endoscopy test; and 39 Gy, 37 Gy, 39 Gy, and 39 Gy for the nasal-related symptom scoring test. The modified saccharin assay, endoscopy test, and SNOT-20 survey revealed that a low dose (< threshold dose) of IMRT was associated with higher mucocilia transport rate (MRT), better endoscopy test score, and improved SNOT-20 score. The patients who received IMRT at a dose less than the threshold had the least damaged nasal mucosa morphology, and functional impairment scores were highest at T1 of IMRT. We conclude that nasal mucosa showed the most serious damage within 3 months after IMRT. If the radiation dose can be controlled within the threshold, the nasal mucosa can recover in the following few months, but recovery will be difficult otherwise.

Effects of irradiation with narrowband-ultraviolet B on up-regulation of histamine H1 receptor mRNA and induction of apoptosis in HeLa cells and nasal mucosa of rats.

Narrowband-ultraviolet B (NB-UVB) phototherapy is used for the treatment of atopic dermatitis. Previously, we reported that irradiation with 200 mJ/cm2 of 310 nm NB-UVB suppressed phorbol-12-myristate-13-acetate (PMA)-induced up-regulation of histamine H1 receptor (H1R) gene expression without induction of apoptosis in HeLa cells. However, the effect of NB-UVB irradiation on nasal symptoms is still unclear. Here, we show that low dose irradiation with 310 nm NB-UVB alleviates nasal symptoms in toluene 2,4-diisocyanate (TDI)-sensitized allergy model rats. Irradiation with 310 nm NB-UVB suppressed PMA-induced H1R mRNA up-regulation in HeLa cells dose-dependently at doses of 75-200 mJ/cm2 and reversibly at a dose of 150 mJ/cm2 without induction of apoptosis. While, at doses of more than 200 mJ/cm2, irradiation with 310 nm NB-UVB induced apoptosis. Western blot analysis showed that the suppressive effect of NB-UVB irradiation on H1R gene expression was through the inhibition of ERK phosphorylation. In TDI-sensitized rat, intranasal irradiation with 310 nm NB-UVB at an estimated dose of 100 mJ/cm2 once a day for three days suppressed TDI-induced sneezes and up-regulation of H1R mRNA in nasal mucosa without induction of apoptosis. These findings suggest that repeated intranasal irradiation with low dose of NB-UVB could be clinically used as phototherapy of AR.

Non-thermal plasma treated solution with potential as a novel therapeutic agent for nasal mucosa regeneration.

Adequate and rapid mucosal regeneration is one of the most important factors in the healing process of nasal mucosa after surgery or trauma. In particular, delayed mucosal regeneration after surgery is an important cause of surgical failure. However, no effective treatment is available yet. Non-thermal plasma (NTP) has several medical effects, but the existing probe type is limited to local direct treatment. Therefore, we investigated the various effects using liquid type plasma to overcome this limitation. In addition, the therapeutic effects of non-thermal plasma treated solution (NTS) on nasal mucosa have yet to be determined. Experiments were carried out using BEAS-2B, a human bronchial epithelial cell line similar to nasal mucosa epithelium. NTS had no cytotoxicity to the BEAS-2B cells and enhanced cell proliferation. NTS also promoted migration of BEAS-2B cells. NTS increased cell proliferation and migration via epidermal growth factor receptor (EGFR) activities and epithelial-to-mesenchymal transition (EMT) signaling. Furthermore, NTS enhanced wound healing of nasal mucosa in an animal model. Accordingly, NTS promotes nasal mucosa wound healing by increasing cell proliferation and migration. These findings suggest the therapeutic potential of NTS in nasal mucosa wound healing.

Conditioned medium from umbilical cord mesenchymal stem cells improves nasal mucosa damage by radiation.

OBJECTIVES: To explore therapeutic effects of conditioned medium from human umbilical cord mesenchymal stem cells (hUC-MSCs) on nasal mucosa radiation damage both in vivo and in vitro. RESULTS: The mucus cilia clearance time (7 and 30 days), degree of mucosal edema (7, 30, 90 and 180 days), cilia coverage (180 days) of concentrated conditioned medium group improved compared with radiotherapy control group. The proliferation and migration abilities of irradiated and non-irradiated nasal epithelial cells significantly increased after culture in bronchial epithelial cell growth medium (BEGM) containing 10% conditioned medium of hUC-MSCs compared to cells cultured in BEGM alone. CONCLUSIONS: Soluble factors secreted by hUC-MSCs may promote nasal epithelial cell proliferation and migration. Intranasal administration of hUC-MSC conditioned medium effectively repairs nasal mucosa radiation damage.

Contemporary Treatment Approaches to Sinonasal Mucosal Melanoma.

Sinonasal mucosal melanoma (SNMM) is a rare oncological entity that comprises most head and neck mucosal melanomas. SNMM has distinctive genetic background, different from cutaneous melanoma. Survival outcomes among SNMM patients are poor; while there is no clear consensus on the optimal management of SNMM, the primary treatment modality is generally considered to be wide surgical excision, and radiation therapy (RT) is often used in the postoperative adjuvant setting to improve locoregional control. Systemic therapies have demonstrated little or no survival benefit, and most SNMM patients die of distant metastatic disease. Owing to the rarity of the disease, the literature describing treatment approaches for SNMM is lacking and largely limited to isolated case reports and retrospective series. Here, we describe contemporary diagnostic and therapeutic approaches to SNMM based on the most recent molecular and outcome data.

A phase 3 trial of mometasone furoate sinus implants for chronic sinusitis with recurrent nasal polyps.

BACKGROUND: Topical intranasal corticosteroid sprays (INCSs) are standard treatment for nasal polyps (NPs), but their efficacy is reduced by poor patient compliance and impaired access of drug to the sinus mucosa. A corticosteroid-eluting sinus implant was designed to address these limitations in patients with recurrent polyposis after sinus surgery by delivering 1350 µg of mometasone furoate (MF) directly to the ethmoid sinus mucosa over approximately 90 days. METHODS: A randomized, sham-controlled, double-blind trial was undertaken in 300 adults with refractory chronic rhinosinusitis with NPs (CRSwNP), who were candidates for repeat surgery. Eligible patients were randomized (2:1) and underwent in-office bilateral placement of 2 implants or a sham procedure. All patients used the MF INCS 200 µg once daily. Co-primary efficacy endpoints were the change from baseline in nasal obstruction/congestion score and bilateral polyp grade, as determined by an independent panel based on centralized, blinded videoendoscopy review. RESULTS: Patients treated with implants experienced significant reductions in both nasal obstruction/congestion score (p = 0.0074) and bilateral polyp grade (p = 0.0073) compared to controls. At day 90, implants were also associated with significant reductions in 4 of 5 prespecified secondary endpoints compared to control: proportion of patients still indicated for repeat sinus surgery (p = 0.0004), percent ethmoid sinus obstruction (p = 0.0007), nasal obstruction/congestion (p = 0.0248), and decreased sense of smell (p = 0.0470), but not facial pain/pressure (p = 0.9130). One patient experienced an implant-related serious adverse event (epistaxis). CONCLUSION: Significant improvements over a range of subjective and objective endpoints, including a reduction in the need for sinus surgery by 61%, suggest that MF sinus implants may play an important role in management of recurrent NP.

Correlation among ocular surface disease, xerostomia, and nasal symptoms in patients with differentiated thyroid carcinoma subjected to radioiodine therapy: A prospective comparative study.

BACKGROUND: Some complications of radioiodine therapy have been reported, but the involvement of the eyes and adnexa is rarely discussed. The purpose of this study was to determine the correlation among ocular surface changes, xerostomia, and changes in the nasal mucosa associated with radioiodine therapy. METHODS: Patients subjected to radioiodine therapy (group 1) or not subjected (group 2) were prospectively evaluated by examinations of the ocular surface and tear film, saliva production, and nasal endoscopy. Ocular and nasal symptoms and xerostomia were evaluated using questionnaires. RESULTS: Evaluation of the ocular surface did not indicate significant differences between the groups. Nasal endoscopy revealed higher mucosal pallor in group 1 and worsening of the endoscopic appearance. Worsening of ocular symptoms and nasal symptoms, xerostomia, and a significant decrease in salivary production was also observed in group 1. CONCLUSION: Subjective worsening of xerostomia, xerophthalmia, nasal symptoms, and changes in the nasal mucosa in group 1 was observed.

How does radioactive iodine affect the nose?

OBJECTIVES/HYPOTHESIS: To determine the effect of radioactive iodine (RAI) treatment on the nasal mucosa and nasal functions. STUDY DESIGN: Prospective clinical study. METHODS: This study included 41 patients (31 female and 10 male) who were treated with RAI for papillary thyroid carcinoma. A visual analogue scale (VAS) was used for subjective evaluation of nasal symptoms. The saccharine test, nasal Schirmer test, and acoustic rhinometry were used for objective evaluation of nasal functions. All tests were administered at baseline (before RAI treatment), and then 1 month and 1 year post-RAI treatment. Only 21 of the patients could be evaluated after 1 year of treatment and were included in the study's analysis. RESULTS: VAS obstruction and dryness scores 1 month and 1 year post-RAI were significantly higher than the baseline scores (P < .05 and P < .05, respectively). Mean cross-sectional area values 1 month and 1 year post-RAI did not differ significantly from baseline values (P > .05 and P > .05, respectively). Schirmer test results 1 month and 1 year post-RAI treatment were significantly lower than at baseline (P < .05 and P < .05, respectively). Saccharine test results 1 month and 1 year post-RAI were significantly higher than at baseline (P < .05). CONCLUSIONS: RAI treatment can adversely affect the nasal mucosa. Nasal dryness and obstruction can occur immediately after RAI treatment. Additional research is warranted to further elucidate the effects of RAI treatment on nasal function. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:2698-2702, 2017.

Treatment for retropharyngeal metastatic undifferentiated squamous cell carcinoma from an unknown primary site: results of a prospective study with irradiation to nasopharyngeal mucosa plus bilateral neck.

Background and Objetive: To evaluate treatment outcomes for patients with retropharyngeal metastatic undifferentiated squamous cell carcinoma (SCC) from an unknown primary site. METHODS: From January 2005 to January 2015, patients who presented with enlarged retropharyngeal nodes underwent transoral sonography-guided fine-needle aspiration to confirm histology. Those with metastatic undifferentiated SCC with unknown primary tumors were treated with radical radiotherapy to nasopharyngeal mucosa plus bilateral neck. Chemotherapy was administered for patients staged N2-3. Endpoints included metastatic nodes control, the appearance of primary tumor, overall survival and treatment-related toxicities. RESULTS: A total of 49 patients were recruited into this study. Retropharyngeal and cervical nodal disease was controlled in 96% of all patients. The incidence of occult primary cancer appearance was 8%. No primary cancer other than of the nasopharynx was detected during the course of follow-up. Ten patients developed distant metastases. The 5-year overall survival, progression-free survival, regional relapse free survival, distant metastasis free survival were 79.6%, 61.1%, 83.4%, 73.8%, respectively. Common late adverse effects included xerostomia (57%) and hearing impairment (35%). CONCLUSION: Radical radiotherapy to both the nasopharynx and bilateral neck can achieve excellent outcome with mild toxicities for patients with retropharyngeal metastatic undifferentiated squamous cell carcinoma from an unknown primary site.

Brachytherapy for radiotherapy-resistant head and neck cancer: A review of a single center experience.

OBJECTIVES/HYPOTHESIS: Despite advances in radiotherapy and chemotherapy treatments for head and neck cancers, the local failure rate is high. In most radiotherapy-resistant cases, surgery is performed; however, some cases are considered unresectable. No standard treatment for these situations has been established. In this study, we review our experience with brachytherapy (BT), which has a different biological mechanism than standard radiotherapy. METHODS: All patients received prior radiation to the recurrence area. Median high-dose radiation BT dose was 50 Gy, administered in 5 to 10 Gy fractions twice daily for 5 days. High-dose radiation was given via four to 10 catheters inserted under local anesthesia (3 patients) or general anesthesia with preventive tracheostomy (10 patients). RESULTS: Thirteen patients received BT from 2010 to 2014. Male:female ratio was 1.6:1, and median age was 66 years (range 23-89). Of those 13 patients, 10 patients were diagnosed with squamous cell carcinoma (SCC) of the oral cavity, two patients with SCC of the nasal mucosa, and one patient with eccrine duct carcinoma. Prior radiation dose ranged from 60 to 70 Gy. Local control was achieved in 11 of 13 patients; only 15.3% (2 of 13) had in-field recurrence. Five patients developed local out-of-field recurrence, and two developed distant metastases. Five patients are alive with no evidence of disease. No major toxicities were encountered. Two patients had severe mucositis and recovered within several weeks. CONCLUSION: Brachytherapy for radiotherapy-resistant head and neck cancers is feasible with minor adverse events, which enables good local control. However, many advanced head and neck cancers develop regional or distant metastases; therefore, additional treatment should be suggested. LEVEL OF EVIDENCE: 4. Laryngoscope, 126:2246-2251, 2016.

Phase II study of proton beam therapy as a nonsurgical approach for mucosal melanoma of the nasal cavity or para-nasal sinuses.

PURPOSE: The aim of this phase II study was to assess the clinical benefit of proton beam therapy for mucosal melanoma of the nasal cavity and para-nasal sinuses. MATERIALS AND METHODS: N0M0 mucosal melanoma of the nasal cavity and para-nasal sinuses were enrolled. Proton therapy was delivered three times per week with a planned total dose of 60 GyE in 15 fractions. Primary endpoint was local control rate at 1 year after treatment. Based on the results of a pilot study, the local control rate was estimated at 75%. RESULTS: Thirty-two patients were enrolled from June 2008 through October 2012. Patient characteristics were as follows: median age 73 years (range, 36-89 years); male/female ratio, 12/20; and T stage 3/4, 11/21. Local control rate at 1 year was 75.8% (95% CI: 63.8-92.4%). With a median follow-up period of 36.4 months, 3-year overall survival rate was 46.1%. The most frequent pattern of first failure was distant metastasis. The main cause of death was cancer death due to distant metastases (93.3%). CONCLUSIONS: Proton beam therapy showed sufficient local control benefits for mucosal melanoma as an alternative treatment of surgery.

Oncocytic Schneiderian Papilloma of the Sinonasal Tract Treated With Radiotherapy.

A 66-year-old man visited the ophthalmology department due to epiphora and was subsequently diagnosed with oncocytic schneiderian papilloma. Surgical removal was recommended to the patient; however, he refused this option. Therefore, a radiation of 64 gray (Gy) was administered in 32 daily doses (2 Gy daily) over 45 days using intensity-modulated radiotherapy. Four months after radiotherapy, the tumor had disappeared. Two years postradiotherapy, the patient was healthy, without tumor recurrence or the development of orbital complications. The authors suggest that radiotherapy could be an adjuvant or definite treatment modality for patients of oncocytic schneiderian papilloma unsuitable for complete surgical removal, or those associated with a high risk of surgery-related complications.

Histopathological effects of intranasal phototherapy and nasal corticosteroids in allergic rhinitis in a rabbit model.

Allergic rhinitis is one of the most common health problems and has a major effect on quality of life. Although new-generation antihistamines and nasal steroids are the main treatment options, complete resolution cannot be obtained in some patients. Besides common side effects such as nasal irritation and epistaxis, the use of these drugs is controversial in some patients, such as pregnant or breastfeeding women. These findings highlight the need for new treatment options. Although phototherapy has been successfully used in the treatment of atopic dermatitis, which is an IgE-mediated disease and shares several common pathogenic features with allergic rhinitis, there are limited studies about its role in the treatment of allergic rhinitis. In this study, we aimed to evaluate and compare the histopathological effects of intranasal phototherapy (Rhinolight) and nasal corticosteroid treatment on the nasal mucosa in allergic rhinitis in a rabbit model and we found that both treatment options significantly reduced inflammation in the nasal mucosa without increasing apoptosis of mucosal cells.

The effects of 2100-MHz radiofrequency radiation on nasal mucosa and mucociliary clearance in rats.

BACKGROUND: Nasal mucociliary clearance has an important role in voiding the airways from inhaled foreign substances. This activity could be disturbed by environmental factors such as radiofrequency radiation. The aim of the present study was to investigate short-term and relatively long-term effects of 2100-MHz radiofrequency radiation emitted by a generator, simulating a 3G-mobile phone, on the nasal septal mucosa and mucociliary clearance in rats. METHODS: Thirty Wistar albino rats were divided into 4 groups. There were 6 rats in Group A and Group B, which served as the control groups (10-day and 40-day groups, respectively). Groups C (10-day exposure) and D (40-day exposure) were both composed of 9 rats; they comprised the radiofrequency radiation exposure groups. The rats in groups C and D were exposed to 2100-MHz radiofrequency radiation emitted by a generator, simulating a 3G-mobile phone, 6 hours/day, for 10 or 40 days, respectively. After exposure, nasal mucociliary clearance was measured by rhinoscintigraphy. After euthanization, the nasal septa of the animals were removed, and tissue samples of the nasal mucosa were examined using a transmission electron microscope. RESULTS: The differences in mucociliary clearances between groups A and C, groups B and D, and groups C and D were found to be statistically significant (p = 0.005, p < 0.001, p < 0.001, respectively). Although there were no histopathological abnormalities in the control groups, the exposure groups showed a number of degenerated and apoptotic cells, ciliary disorganization and ciliary loss in the epithelial cells, epithelial metaplasia, alteration of normal chromatin distribution and karyolysis in nuclei, changes in the basal cells, and lymphocytic infiltration. The histopathological changes were more severe in group D. CONCLUSION: Radiofrequency radiation at 2100 MHz damaged the nasal septal mucosa, and disturbed the mucociliary clearance. Ciliary disorganization and ciliary loss in the epithelial cells resulted in deterioration of nasal mucociliary clearance.

Nasal cytological changes as late effects of radiotherapy for nasopharyngeal cancer.

BACKGROUND: Radiation therapy is a cornerstone in nasopharyngeal cancer treatment. However, it can induce acute and long-term adverse effects, such as acute mucositis and late submucosal fibrosis. Late toxicities could not only affect submucosa but also mucosal cells, determining long-term cytological changes. OBJECTIVE: Evaluation of delayed nasal cytological alterations in patients who underwent radiation therapy for nasopharyngeal carcinoma (NPC). METHODS: In this case-control study, we analyzed 30 healthy subjects and 30 patients treated with chemotherapy and radiotherapy for NPC between 2003 and 2011, with a median follow-up of 59 months. All subjects underwent symptoms anamnestic evaluation (rhinorrea, nasal obstruction), endoscopic fiber optic nasal examination, skin-prick tests, and nasal scraping for cytological exam. RESULTS: A higher percentage of rhinorrhea, nasal obstruction, mucosal hyperemia, and presence of nasopharyngeal secretions at fiber optic endoscopic exam was found in radiated subjects (p < 0.05). Nasal cytology analysis demonstrated a higher percentage of neutrophilic inflammation and squamous cell metaplasia and mucous cell metaplasia in treated patients (p < 0.05). No cytological atypia was seen. No statistically significant correlation between nasal cytological changes and objective findings, patients' age, tobacco smoking, and gastroesophageal reflux has been found in the radiotherapy group (p > 0.05). CONCLUSION: Radiation therapy induces late nasal mucosal changes, which may be related to clinical consequences, such as abundant mucus production and its consequent endonasal stagnation. In the future, detailed knowledge of cytological changes in patients' nasal mucosa could represent a key prerequisite for the choice of effective interventions for late radiation-induced rhinitis.

The effects of a 1.8 GHz continuous electromagnetic fields on mucociliary transport of human nasal mucosa.

OBJECTIVES/HYPOTHESIS: The aim of this study was to investigate the effects of a 1.8 GHz continuous electromagnetic fields (EMF) on human nasal mucociliary transport, and to determine the pathophysiology of ciliary beat frequency (CBF) during an EMF-induced change. METHODS: Human nasal mucosa cells were exposed to a 1.8 GHz EMF (SAR=1.0 W/kg), and CBF was analyzed using an optical flow technique with the peak detection method. RESULTS: The 1.8 GHz-exposed group showed a decreased CBF when compared to the control group. In the cytotoxicity assay, difference in survival rates was not found between the two groups. In the EMF-exposed group, protein kinase C (PKC) activity was increased during a PKC activity assay. The broad PKC inhibitor, Calphostin C abolished the EMF-induced decrease of CBF. The EMF-induced decrease of CBF was abolished by GF 109203X, a novel PKC (nPKC) isoform inhibitor, whereas the decrease was not attenuated by Gö-6976, a specific inhibitor of conventional PKC (cPKC) isoform. CONCLUSIONS: EMF may inhibit CBF via an nPKC-dependent mechanism. Therefore, we have confirmed that EMF could decrease CBF by increasing PKC activity.

Laser phototherapy as a treatment for radiotherapy-induced oral mucositis.

Oral mucositis is a harmful side effect of radiotherapy (RT) on the head and neck region. There are encouraging reports on the beneficial aspects of the use of laser light on the treatment of oral mucositis. This paper reports the efficacy of laser phototherapy (LPT) on the treatment of oral mucositis in a patient undergoing RT after surgical removal of a squamous cell carcinoma with osseous invasion of the maxilla. Palatal and commissural lesions were treated with λ660 nm, 40 mW, ∅=4 mm(2), in contact mode, 5 x 2.4 J/cm(2) per point, 14.4 J/cm(2) per session. For treating the lesion on the patient's nasal mucosa, LPT (∅=4 mm(2), λ780 nm, 70 mW, 3 x 2.1 J/cm(2) per point, 6.3 J/cm(2) per session, contact mode) was used on the external area of the nose. A single dose (2.4 J/cm(2)) with the λ660 nm laser, as described before, was applied on the entrance of each nostril. LPT was used 3 times/week during 4 weeks. Treatment results indicate that the use of LPT on oral mucositis was effective and allowed the patient to carry on the RT without interruption. However, long-term and controlled clinical trials are necessary to establish both preventive and curative protocols using LPT.

Proton beam therapy as a nonsurgical approach to mucosal melanoma of the head and neck: a pilot study.

PURPOSE: The aim of this pilot study was to assess the clinical benefit of proton beam therapy for mucosal melanoma of the head and neck. METHODS AND MATERIALS: Patients with mucosal melanoma of the head and neck with histologically confirmed malignant melanoma and N0 and M0 disease were enrolled. Proton therapy was delivered three times per week with a planned total dose of 60 Gy equivalents (GyE) in 15 fractions. RESULTS: Fourteen consecutive patients were enrolled from January 2004 through February 2008. Patient characteristics were as follows: median age 73 years old (range, 56 to 79 years); male/female ratio, 7/7; and T stage 1/2/3/4, 3/2/0/9. All patients were able to receive the full dose of proton therapy. The most common acute toxicities were mucositis (grade 3, 21%) and mild dermatitis (grade 3, 0%). As for late toxicity, 2 patients had a unilateral decrease in visual acuity, although blindness did not occur. No treatment-related deaths occurred throughout the study. Initial local control rate was 85.7%, and, with a median follow-up period of 36.7 months, median progression-free survival was 25.1 months, and 3-year overall survival rates were 58.0%. The most frequent site of first failure was cervical lymph nodes (6 patients), followed by local failure in 1 patient and lung metastases in 1 patient. On follow-up, 5 patients died of disease, 4 died due to cachexia caused by distant metastases, and 1 patient by carotid artery perforation cause by lymph nodes metastases. CONCLUSIONS: Proton beam radiotherapy showed promising local control benefits and would benefit from ongoing clinical study.

Laser phototherapy as a treatment for radiotherapy-induced oral mucositis

Oral mucositis is a harmful side effect of radiotherapy (RT) on the head and neck region. There are encouraging reports on the beneficial aspects of the use of laser light on the treatment of oral mucositis. This paper reports the efficacy of laser phototherapy (LPT) on the treatment of oral mucositis in a patient undergoing RT after surgical removal of a squamous cell carcinoma with osseous invasion of the maxilla. Palatal and commissural lesions were treated with λ660 nm, 40 mW, ∅=4 mm², in contact mode, 5 x 2.4 J/cm² per point, 14.4 J/cm² per session. For treating the lesion on the patient's nasal mucosa, LPT (∅=4 mm², λ780 nm, 70 mW, 3 x 2.1 J/cm² per point, 6.3 J/cm² per session, contact mode) was used on the external area of the nose. A single dose (2.4 J/cm²) with the λ660 nm laser, as described before, was applied on the entrance of each nostril. LPT was used 3 times/week during 4 weeks. Treatment results indicate that the use of LPT on oral mucositis was effective and allowed the patient to carry on the RT without interruption. However, long-term and controlled clinical trials are necessary to establish both preventive and curative protocols using LPT.

A mucosite oral é um efeito colateral prejudicial da radioterapia na região de cabeça e pescoço. Existem estudos que evidenciam o efeito benéfico do uso da luz laser no tratamento da mucosite oral. O objetivo deste caso clínico foi o de avaliar a eficácia da fototerapia laser no tratamento da mucosite oral em um paciente sendo submetido a radioterapia, após a remoção cirúrgica de um carcinoma escamocelular, com invasão óssea da maxila. As lesões do palato e das comissuras labiais foram tratadas com λ660 nm, 40 mW, ∅=4 mm², em contato, 5 x 2.4 J/cm² por ponto, 14.4 J/cm² por sessão. Na lesão existente na mucosa nasal a fototerapia laser (∅=4 mm², λ780 nm, 70 mW, 3 x 2.1 J/cm² por ponto, 6.3 J/cm² por sessão, em contato) foi utilizada na área externa do nariz. Uma dose única (2.4 J/cm²) com o laser λ660 nm e os parâmetros descritos anteriormente foi aplicado na entrada de cada narina. A fototerapia laser foi utilizada 3 vezes por semana, durante 4 semanas. Os resultados do tratamento são indicativos de que o uso da fototerapia laser em mucosite oral foi efetiva e permitiu ao paciente continuar o tratamento radioterápico sem interrupções. Entretanto, estudos clínicos controlados são necessários para se estabelecer os protocolos, para tratamento e prevenção da mucosite oral, utilizando fototerapia laser.

Molecular response of nasal mucosa to therapeutic exposure to broad-band ultraviolet radiation.

Ultraviolet radiation (UVR) phototherapy is a promising new treatment for inflammatory airway diseases. However, the potential carcinogenic risks associated with this treatment are not well understood. UV-specific DNA photoproducts were used as biomarkers to address this issue. Radioimmunoassay was used to quantify cyclobutane pyrimidine dimers (CPDs) and (6-4) photoproducts in DNA purified from two milieus: nasal mucosa samples from subjects exposed to intranasal phototherapy and human airway (EpiAirway) and human skin (EpiDerm) tissue models. Immunohistochemistry was used to detect CPD formation and persistence in human nasal biopsies and human tissue models. In subjects exposed to broadband ultraviolet radiation, DNA damage frequencies were determined prior to as well as immediately after treatment and at increasing times post-treatment. We observed significant levels of DNA damage immediately after treatment and efficient removal of the damage within a few days. No residual damage was observed in human subjects exposed to multiple UVB treatments several weeks after the last treatment. To better understand the molecular response of the nasal epithelium to DNA damage, parallel experiments were conducted in EpiAirway and EpiDerm model systems. Repair rates in these two tissues were very similar and comparable to that observed in human skin. The data suggest that the UV-induced DNA damage response of respiratory epithelia is very similar to that of the human epidermis and that nasal mucosa is able to efficiently repair UVB induced DNA damage.