Effect of radiotherapy on the levels of secretory immunoglobulin A against indigenous and virulent streptococci

Post-Irradiation Sinus Mucosa Disease in Nasopharyngeal Carcinoma Patients Treated with Intensity-Modulated Proton Therapy

Simple Summary

Chronic rhinosinusitis (CRS) is a common treatment complication in patients with nasopharyngeal carcinoma (NPC) after radiotherapy. In this study, we aimed to investigate the incidence and severity of CRS in NPC patients who underwent intensity-modulated proton therapy (IMPT) by evaluating the sinus mucosa change in imaging studies, and we compared these patients with those who underwent volume-modulated arc therapy (VMAT). This was a retrospective case–control study in which 53 and 54 patients were treated with IMPT and VMAT, respectively. We noted that patients in the IMPT group had a significantly lower incidence and decreased severity of sinus mucosa abnormality than those with VMAT. Better and faster recovery of sinonasal function after radiotherapy in the IMPT group was also observed. IMPT techniques deposit the bulk of their radiation doses in highly confined areas, allowing lower exposure of non-target organs during irradiation, which results in more sinonasal mucosa being retained.

Abstract

In the past decade, patients with nasopharyngeal cancer (NPC) have been deemed candidates for proton radiotherapy, due to the large and comprehensive target volumes and the necessity for the retention of the surrounding healthy tissues. In this study, we aimed to compare the incidence and severity of post-irradiation sinusitis by detecting sinus mucosa diseases (SMDs) via the magnetic resonance imaging (MRI) of patients with NPC after intensity-modulated proton therapy (IMPT) and volume-modulated arc therapy (VMAT). A total of 53 patients in the IMPT group and 54 patients in the VMAT group were enrolled in this study. There were significantly lower endoscopic scores and Lund–Mackay staging scores determined from MRI scans in the IMPT group during different follow-up periods. For the most vulnerable sinuses, the incidence and severity of SMD were the highest during the third post-radiotherapy month in both groups. These decreased steadily, and there was no significant increase in the incidence and severity of SMD during the second post-radiotherapy year in the IMPT group. Our data show that NPC patients with IMPT have a significantly lower incidence and decreased severity of SMD than those with VMAT. A better and faster recovery of sinonasal function after radiotherapy in the IMPT group was also observed.

Respiratory and pulmonary complications in head and neck cancer patients: Evidence-based review for the COVID-19 era

BACKGROUND

Pulmonary complications and infections frequently affect patients with head and neck squamous cell carcinoma (HNSCC). Common characteristics can predispose these patients to the development of severe respiratory illness, which may be particularly relevant during the 2019 coronavirus disease (COVID-19) pandemic.

METHODS

A scoping review was performed to assess the impact of pulmonary comorbidities and adverse respiratory outcomes in HNSCC patients.

RESULTS

Advanced age, history of tobacco and alcohol abuse, and cardiopulmonary comorbidities are significant risk factors for the development of adverse respiratory outcomes. Treatment toxicities from radiation or chemoradiation therapy significantly increase these risks.

CONCLUSION

Respiratory complications are a frequent cause of morbidity and mortality among HNSCC patients, and the COVID-19 pandemic may disproportionately affect this population. Interventions designed to decrease smoking and alcohol use, improve oral hygiene, and aggressively manage medical comorbidities are important to the long-term management and health of these patients.

Choanal fungus ball mimicking a tumour

We report the first case of an isolated choanal fungus ball in a 28-year-old man with a previous history of nasopharyngeal carcinoma, who was treated with radiotherapy 14 years ago. The initial diagnosis was a recurrent tumour or a secondary neoplasm. Histopathological examination confirmed a fungal infection. There are no previous reports of a fungus ball located at the posterior choanal region. Although it has been reported that bacteriology of sinonasal region would be different in irradiated patients, there is no study reporting fungal infections in irradiated patients in English literature. In this report, the clinical presentation, relevant radiologic findings and management of sinonasal fungus ball and its relationship with previous radiotherapy were discussed with the literature knowledge.

Postirradiation Sinus Mucosa Disease in Nasopharyngeal Carcinoma Patients

OBJECTIVES/HYPOTHESIS

We sought to determine the incidence, progression, and risk factors for postirradiation sinus mucosa diseases (SMD) incidentally found on follow-up magnetic resonance images MRIs) in nasopharyngeal carcinoma (NPC) patients.

STUDY DESIGN

RETROSPECTIVE.

METHODS

The medical records, pre- and postradiotherapy (RT) MRIs were reviewed in NPC patients. Lund-Mackay system for staging of rhinosinusitis (Lund score) was used as a tool for investigation.

RESULTS

One hundred twelve NPC patients (77 males and 35 females) were recruited in this study. The distribution of tumor staging in these patients were 39 (34.8%) patients in T1,23(20.5%) in T2, 31(27.7%) in T3, and 19 (17.0%) in T4 by MRI staging before RT. In these 62 patients with normal sinus ventilation before RT, 42 (67.7%) patients returned to having SMDs 3 months after RT. The maxillary,anterior ethmoid, and posterior ethmoid sinuses were most readily affected. In patients with SMDs at 3 months postRT, advanced tumor stage (P = .013) and smoking habit (P =.047) were the two factors that significantly influence Lund score. When comparing Lund score with different times after radiation therapy, a trend of decrease in Lund score could be noted from 3 months to 3 years after irradiation.

CONCLUSIONS

The incidence and severity of SMD was found to be highest at 3 months postRT and decreased gradually with time. Conservative management with clinical symptom correlation should be attempted first in these patients. In these NPC patients,advanced tumor stage and smoking habit would predispose them to SMD development.

Expression of members of the phospholipase A2 family of enzymes in human nasal mucosa

Phospholipase A2 (PLA2) is a family of enzymes thought to play a key role in inflammation by releasing arachidonic acid for the synthesis of eicosanoids and lysophospholipid for the synthesis of platelet-activating factor. However, the precise contribution of different PLA2 types to the formation of inflammatory lipid mediators in the upper airways is not known and the expression of different PLA2 genes in the human nasal mucosa has not been examined. This study therefore investigated the occurrence of messenger ribonucleic acids (mRNAs) for different PLA2 forms (IB, IIA, IID, IIE, III, IVA, IVB, IVC, V, VI, VII, X, acid calcium-independent (aiPLA2), and calcium-independent membrane bound PLA2, (iPLA2-2)) in the nasal mucosa of five healthy human subjects. Using reversed transcription-polymerase chain reaction (RT-PCR) techniques it was found that all these PLA2 types except PLA2 V were expressed in all subjects, whereas PLA2 V was detected in only one individual on one single occasion. The relative abundance of the different PLA2 transcripts were aiPLA2 > X approximately = IVA > IIA approximately = IIE approximately = IVB approximately = VI > IB approximately = IID approximately = III approximately = IVC approximately = VII approximately = iPLA2-2. To further quantify the mRNA-expression of PLA2 X, IVA and IIA, the samples were reanalysed with a quantitative PCR-technique utilizing competitive deoxyribonucleic acid (DNA) mimics as references. The amounts of PLA2 X, IVA and IIA mRNA were then estimated to 0.9 +/- 0.2, 1.1 +/- 0.7, and 0.0025 +/- 0.0021 amol (mean +/- SE), respectively, confirming the relative abundance of these PLA2 transcripts and indicating that the recently described PLA2 X form is relatively strongly expressed. These findings demonstrate that a large number of PLA2 types are expressed in the normal human nasal mucosa. Moreover, this investigation demonstrates, for the first time, the presence of the newly discovered phospholipase A2 forms IID, IIE, III, IVB, IVC, X and calcium-independent membrane bound phospholipase A2 in the human nasal mucosa and raises the possibility that one or several of these may be involved in inflammatory reactions in the nose.

Pneumococcal virulence factors: structure and function

The overall goal for this review is to summarize the current body of knowledge about the structure and function of major known antigens of Streptococcus pneumoniae, a major gram-positive bacterial pathogen of humans. This information is then related to the role of these proteins in pneumococcal pathogenesis and in the development of new vaccines and/or other antimicrobial agents. S. pneumoniae is the most common cause of fatal community-acquired pneumonia in the elderly and is also one of the most common causes of middle ear infections and meningitis in children. The present vaccine for the pneumococcus consists of a mixture of 23 different capsular polysaccharides. While this vaccine is very effective in young adults, who are normally at low risk of serious disease, it is only about 60% effective in the elderly. In children younger than 2 years the vaccine is ineffective and is not recommended due to the inability of this age group to mount an antibody response to the pneumococcal polysaccharides. Antimicrobial drugs such as penicillin have diminished the risk from pneumococcal disease. Several pneumococcal proteins including pneumococcal surface proteins A and C, hyaluronate lyase, pneumolysin, autolysin, pneumococcal surface antigen A, choline binding protein A, and two neuraminidase enzymes are being investigated as potential vaccine or drug targets. Essentially all of these antigens have been or are being investigated on a structural level in addition to being characterized biochemically. Recently, three-dimensional structures for hyaluronate lyase and pneumococcal surface antigen A became available from X-ray crystallography determinations. Also, modeling studies based on biophysical measurements provided more information about the structures of pneumolysin and pneumococcal surface protein A. Structural and biochemical studies of these pneumococcal virulence factors have facilitated the development of novel antibiotics or protein antigen-based vaccines as an alternative to polysaccharide-based vaccines for the treatment of pneumococcal disease.