Submandibular gland transfer: a new method of preventing radiation-induced xerostomia

Current management of xerostomia in head and neck cancer patients

Radiotherapy (RT) continues to play a key role in the management of head and neck cancer (HNC). Xerostomia remains a principal detriment to the quality of life (QoL) for 80 % of surviving patients receiving head and neck radiation. Radiation-induced injury to the salivary glands is dose-dependent, and thus efforts have been focused on decreasing radiation to the salivary glands. Decreased saliva production reduces both short-term and long-term quality of life in head and neck survivors by impacting on taste and contributing to dysphagia. Several radioprotective agents to the salivary gland have been investigated. Although not widely practiced, surgical transfer of the submandibular gland prior to RT is the mainstay of surgical options in preventing xerostomia. This review focuses on the strategies to improve xerostomia following radiation therapy in head and neck cancers.

Submandibular gland transfer for the prevention of radiation-induced xerostomia in oropharyngeal cancer: Dosimetric impact in the intensity modulated radiotherapy era

BACKGROUND

Submandibular gland (SMG) transfer decreased radiation-associated xerostomia in the 2/3-dimensional radiotherapy era. We evaluated the dosimetric implications of SMG transfer on modern intensity modulated radiotherapy (IMRT) plans.

METHODS

Eighteen oropharynx cancer patients underwent SMG transfer followed by IMRT; reoptimized plans using the baseline SMG location were generated. Mean salivary gland, oral cavity, and larynx doses were compared between clinical plans and reoptimized plans.

RESULTS

No statistically significant difference in mean SMG dose (27.53 Gy vs. 29.61 Gy) or total salivary gland dose (26.12 Gy vs. 26.41 Gy) was observed with or without SMG transfer (all p > 0.05). Mean oral cavity and larynx doses were not statistically different. Neither tumor site, target volume crossing midline, stage, nor salivary gland volumes were associated with mean doses.

CONCLUSIONS

Salivary gland doses were similar with or without SMG transfer. IMRT likely decreases the benefit of SMG transfer on the risk of radiation-associated xerostomia.

Modelling Radiation-Induced Salivary Dysfunction during IMRT and Chemotherapy for Nasopharyngeal Cancer Patients

BACKGROUND

Radiation-induced xerostomia is one of the most prevalent adverse effects of head and neck cancer treatment, and it could seriously affect patients' qualities of life. It results primarily from damage to the salivary glands, but its onset and severity may also be influenced by other patient-, tumour-, and treatment-related factors. We aimed to build and validate a predictive model for acute salivary dysfunction (aSD) for locally advanced nasopharyngeal carcinoma (NPC) patients by combining clinical and dosimetric factors.

METHODS

A cohort of consecutive NPC patients treated curatively with IMRT and chemotherapy at 70 Gy (2-2.12 Gy/fraction) were utilised. Parotid glands (cPG, considered as a single organ) and the oral cavity (OC) were selected as organs-at-risk. The aSD was assessed at baseline and weekly during RT, grade ≥ 2 aSD chosen as the endpoint. Dose-volume histograms were reduced to the Equivalent Uniform Dose (EUD). Dosimetric and clinical/treatment features selected via LASSO were inserted into a multivariable logistic model. Model validation was performed on two cohorts of patients with prospective aSD, and scored using the same schedule/scale: a cohort (NPC_V) of NPC patients (as in model training), and a cohort of mixed non-NPC head and neck cancer patients (HNC_V).

RESULTS

The model training cohort included 132 patients. Grade ≥ 2 aSD was reported in 90 patients (68.2%). Analyses resulted in a 4-variables model, including doses of up to 98% of cPG (cPG_D98%, OR = 1.04), EUD to OC with n = 0.05 (OR = 1.11), age (OR = 1.08, 5-year interval) and smoking history (OR = 1.37, yes vs. no). Calibration was good. The NPC_V cohort included 38 patients, with aSD scored in 34 patients (89.5%); the HNC_V cohort included 93 patients, 77 with aSD (92.8%). As a general observation, the incidence of aSD was significantly different in the training and validation populations (p = 0.01), thus impairing calibration-in-the-large. At the same time, the effect size for the two dosimetric factors was confirmed. Discrimination was also satisfactory in both cohorts: AUC was 0.73, and 0.68 in NPC_V and HNC_V cohorts, respectively.

CONCLUSION

cPG D98% and the high doses received by small OC volumes were found to have the most impact on grade ≥ 2 acute xerostomia, with age and smoking history acting as a dose-modifying factor. Findings on the development population were confirmed in two prospectively collected validation populations.

Radiation therapy in head and neck cancer

This review summarizes the beginning of radiotherapy, techniques of modern radiation therapy with different types, toxicities induced by radiotherapy and their management. Head and neck radiation therapy is still improving for the better management and control of the cancer and induced radiotherapy toxicities.

Does Submandibular Gland Sacrificing Neck Dissection Decrease Salivary Output and Quality of Life?

PURPOSE

Our study aimed to quantify the impact of submandibular gland (SMG) resection during Level I neck dissection (ND) on stimulated salivary output (SSO) and xerostomia-related quality of life in patients with head and neck cancer (HNC).

METHODS

A retrospective cohort was formed from 32 patients that underwent unilateral or bilateral Level I ND and a control group of 23 patients that had level II-IV ND. SSO (Saxon test) and University of Washington Quality of Life survey results for both groups were compared.

RESULTS

Mean SSO was 3.41 g in the SMG resection group and 3.86 g in the control group, with no significant statistical difference. There was no difference in mean SSO between patients with 2 SMGs, a single remaining SMG, or no glands. The mean SSO of SMG resection cases with a history of adjuvant RT was 2.61 g which was below the xerostomia threshold for the Saxon test (2.75 g) and control group patients with RT had a significantly higher mean SSO (4.07 g). The lowest UW-QoL saliva domain score average (53.8) was in the SMG-resected, RT-positive group.

CONCLUSION

Results indicate unilateral or bilateral resection of SMG does not reduce SSO to a significant extent. Adjuvant radiotherapy and SMG resection are additive risk factors for xerostomia and the related loss in quality of life. SMG sparing may be necessary in HNC patients with higher risk for the need of adjuvant radiation.

[Late toxicity following primary conservative treatment : Dysphagia and xerostomia]

Dysphagia and xerostomia are still among the most important acute and late side effects of radiotherapy. Technical developments over the past two decades have led to improved diagnostics and recognition as well as understanding of the causes of these side effects. Based on these findings and advances in both treatment planning and irradiation techniques, the incidence and severity of treatment-associated radiogenic late sequelae could be clearly reduced by the use of intensity-modulated radiotherapy (IMRT), which could contribute to marked long-term improvements in the quality of life in patients with head and neck cancer. Highly conformal techniques, such as proton therapy have the potential to further reduce treatment-associated side effects in head and neck oncology and are currently being prospectively tested within clinical trial protocols at several centers.

Coconut Oil as a Novel Approach to Managing Radiation-Induced Xerostomia: A Primary Feasibility Study

Background

Xerostomia is a common complication following radiation therapy for head and neck cancer (HNC), for which there is no single, universally accepted therapy. Coconut oil has been anecdotally suggested to provide relief for this complication. This study sought to examine the feasibility and effectiveness of coconut oil as a therapy for radiation-induced xerostomia.

Methods

A feasibility study was performed among 30 patients with xerostomia subsequent to radiation for HNC. Coconut oil samples were provided along with a protocol for use over a 2-week period and the option to continue if they found it beneficial. Patients were also instructed to keep diaries to document their patterns of use. The Xerostomia-related Quality of Life Scale (XeQOLS) was administered at baseline and 3-month follow-up. Descriptive methods were used to summarize patterns of coconut oil use and paired t-tests were used to assess changes in XeQOLS scores over time.

Results

The mean total duration of coconut oil use during the study period was 16 days (1-71). The average number of uses per day was 3 (1-5), with an average amount per use of 5 mL (1.2-8.5). Twelve patients (41.4%) continued coconut oil use beyond the advised period. There was no statistically significant difference in XeQOLS scores pre- and post-treatment. There were no adverse events during the study period.

Conclusions

The use of coconut oil as a treatment strategy for xerostomia post-HNC radiation is feasible, inexpensive, and safe. This study demonstrates that there may be a group of HNC patients that benefit from its use.

Modified technique of submandibular gland transfer followed by intensity modulated radiotherapy to reduce xerostomia in head and neck cancer patients

BACKGROUND

Xerostomia is one of the most common long-term adverse effects of radiotherapy for head and neck cancer patients. Contralateral submandibular gland transfer (SMG-T) before radiotherapy was shown to reduce xerostomia compared to pilocarpine. We sought to evaluate a modification of this surgery preserving the ipsilateral facial artery and vein to simplify the SMG-T.

METHODS

Eighteen patients planned for head and neck intensity modulated radiotherapy to both necks were reviewed. Surgical complications were recorded. The grade of xerostomia was assessed after treatment completion.

RESULTS

There were no minor or major complications resulting from the modified SMG-T. At 24.5-months follow up, the incidence of post-treatment moderate to severe xerostomia was 16.7%. No locoregional recurrence occurred. Only one patient had distant solitary lung metastasis.

CONCLUSION

The modified SMG-T technique is a practical and effective method to reduce the dose of radiation to the contralateral SMG and limit post-treatment xerostomia.

The Multidisciplinary Team (MDT) Approach and Quality of Care

The core function of a multidisciplinary team (MDT) is to bring together a group of healthcare professionals from different fields in order to determine patients' treatment plan. Most of head and neck cancer (HNC) units are currently led by MDTs that at least include ENT and maxillofacial surgeons, radiation and medical oncologists. HNC often compromise relevant structures of the upper aerodigestive tract involving functions such as speech, swallowing and breathing, among others. The impairment of these functions can significantly impact patients' quality of life and psychosocial status, and highlights the crucial role of specialized nurses, dietitians, psycho-oncologists, social workers, and onco-geriatricians, among others. Hence, these professionals should be integrated in HNC MDTs. In addition, involving translational research teams should also be considered, as it will help reducing the existing gap between basic research and the daily clinical practice. The aim of this comprehensive review is to assess the role of the different supportive disciplines integrated in an MDT and how they help providing a better care to HNC patients during diagnosis, treatment and follow up.

Five-year outcomes of sparing level IB in node-positive, human papillomavirus-associated oropharyngeal carcinoma: A safety and efficacy analysis

INTRODUCTION

The conformality of modern intensity modulated radiation therapy (IMRT) allows avoidance of the submandibular glands (SMG) in select patients, potentially improving late xerostomia. This study explores the safety and efficacy of this approach in select oropharyngeal carcinoma (OPC) patients.

METHODS

Patients with T1-2N+ human papillomavirus (HPV)-associated OPC treated with definitive IMRT at one institution from 2009 to 2014 were identified. Patients were divided into 3 groups: bilateral level IB targeted (A, n = 16), a single level IB targeted (B, n = 61), and bilateral IB spared (C, n = 9). Outcomes were reviewed to identify the rate of level IB regional recurrence. Odds ratios were calculated for xerostomia between groups.

RESULTS

Level Ib was targeted in 93 instances (54.1%) and avoided in 79 instances (45.9%). Mean SMG doses were significantly lower when level IB was spared compared to when targeted (37.5 Gy vs 67.5 Gy; P < 0.0001). Median doses to oral cavity decreased with increasing level Ib sparing (40.7 Gy [A] vs 35.4 Gy [B] vs 30.7 [C]; P = 0.002). The rate of late grade ≥2 xerostomia was significantly lower in patients with bilateral 1b sparing (53% in A vs 0% in C; P = 0.007). Sparing 1b unilaterally resulted in a non-significant decrease in late grade ≥2 xerostomia (P = 0.181). No regional failures were identified in levels IB (median follow up = 59.3 months).

CONCLUSION

Sparing level IB is safe in T1-2N+ HPV+ OPC. Avoiding level Ib translates into significantly lower SMG and oral cavity doses. Larger studies are needed to validate these findings and the impact of this technique.

Determinants of level Ib involvement in oral squamous cell carcinoma and implications for submandibular gland-sparing neck dissection

Traditional neck dissection for oral squamous cell carcinoma (OSCC) involves removal of the submandibular salivary gland. Several studies have cited the low incidence of direct gland invasion by tumours and have recommended gland-sparing neck dissection. In this study, a detailed audit of level Ib involvement in OSCC was performed in order to assess the feasibility of submandibular gland-sparing in neck dissection; the rate of direct involvement by the primary tumours, the involvement of periglandular level Ib nodes, and their determinants were investigated. A total of 586 neck dissection specimens obtained between 2005 and 2014 from patients operated on at the study institution for floor of mouth, tongue, and buccal primaries, were evaluated for direct invasion of the gland and periglandular lymphadenopathy. Of 226 node-positive patients, 21 (9.3%) had direct gland invasion by tumour. Risk factors were tumour diameter >4cm (P=0.002) and depth of invasion >10mm (P=0.003). Determinants of periglandular lymphadenopathy were depth of invasion >10mm (P<0.001), perineural invasion (P=0.02), lymphovascular invasion (P=0.014), and moderate/poor differentiation (P<0.0001). Gland-sparing neck dissection is safe in early tumours (pT1pN0-1), with a good chance of minimizing xerostomia without radiotherapy. Larger tumours without clear evidence of submandibular gland invasion or suspicious level Ib lymphadenopathy may be considered for gland preservation, however the oncological safety is unclear.

Submandibular Gland Transfer: A Potential Imaging Pitfall

BACKGROUND AND PURPOSE

The Seikaly and Jha submandibular gland transfer surgery is performed to facilitate gland shielding during radiation therapy for head and neck tumors to circumvent radiation-induced xerostomia. It results in an asymmetric postsurgical appearance of the submandibular and submental spaces. Our purpose was to characterize the morphologic and enhancement characteristics of the transferred submandibular gland and identify potential pitfalls in postoperative radiologic interpretation.

MATERIALS AND METHODS

This retrospective study identified patients with head and neck cancer who had undergone the submandibular gland transfer procedure at our institution. Chart reviews were performed to identify relevant oncologic histories and therapies. CT and MR neck imaging was reviewed to characterize morphologic and enhancement characteristics of the pre- and postoperative submandibular glands, as well as interpretive accuracy.

RESULTS

Eleven patients with oropharyngeal and nasopharyngeal squamous cell carcinomas who underwent submandibular gland transfer were identified. The transferred glands were significantly lengthened in the anteroposterior dimension compared with contralateral glands (P < .001) and displaced anteriorly and inferiorly within the submandibular and submental spaces. Enhancement patterns of the transferred submandibular glands varied, depending on the time of imaging relative to the operation and radiation therapy. Submandibular gland transfer was acknowledged in the postoperative report in 7/11 cases. Errors in interpretation were present in 2/11 reports.

CONCLUSIONS

After the submandibular gland transfer procedure, the submandibular and submental spaces lose their symmetric appearances as the transferred submandibular glands become lengthened and located more anteriorly and inferiorly, with variable enhancement characteristics. Familiarity with the postsurgical appearance of the transferred submandibular glands is key to accurate imaging interpretation.

Free thyroid transfer: Short-term results of a novel procedure to prevent post-radiation hypothyroidism

Background

The incidence of radiation‐induced hypothyroidism (RIH) in patients with head and neck cancer is >50%. The purpose of this study was to assess the long‐term efficacy of free thyroid transfer (FTT) for prevention of RIH in patients with head and neck cancer.

Methods

Hemithyroid dissection was completed in 10 patients with advanced head and neck cancer undergoing ablation, radial forearm free flap (RFFF) reconstruction, and postoperative radiotherapy (RT). The hemithyroid was anastomosed to the donor site vessels in the forearm. Thyroid laboratory testing and technetium (Tc) scans were performed 6 weeks and 12 months postoperatively to establish functional integrity.

Results

FTT was successfully performed in 9 of 10 recruited patients. Postoperative Tc scans demonstrated strong Tc uptake in the forearm donor site at 6 weeks and 12 months in all patients who underwent transplantations.

Conclusion

FTT is feasible with maintenance of function, and may represent a novel strategy for prevention of RIH. © 2016 Elsevier Head & Neck Published by Wiley Periodicals, Inc. Head Neck39: 1234–1238, 2017

Electromyography and Mechanomyography Signals During Swallowing in Healthy Adults and Head and Neck Cancer Survivors

Surface electromyography (sEMG) is used as an adjuvant to dysphagia therapy to demonstrate the activity of submental muscles during swallowing exercises. Mechanomyography (MMG) has been suggested as a potential superior alternative to sEMG; however, this advantage is not confirmed for signal acquired from submental muscles. This study compared the signal-to-noise ratio (SNR) obtained from sEMG and MMG sensors during swallowing tasks, in healthy participants and those with a history of head and neck cancer (HNC), a population with altered anatomy and a high incidence of dysphagia. Twenty-two healthy adults and 10 adults with a history of HNC participated in this study. sEMG and MMG signals were acquired during dry, thin liquid, effortful, and Mendelsohn maneuver swallows. SNR was compared between the two sensors using repeated measures ANOVAs and subsequent planned pairwise comparisons. Test-retest measures were collected on 20 % of participants. In healthy participants, MMG SNR was higher than that of sEMG for dry [t(21) = -3.02, p = 0.007] and thin liquid swallows [t(21) = -4.24, p < 0.001]. Although a significant difference for sensor was found in HNC participants F(1,9) = 5.54, p = 0.043, planned pairwise comparisons by task revealed no statistically significant difference between the two sensors. sEMG also showed much better test-retest reliability than MMG. Biofeedback provided as an adjuvant to dysphagia therapy in patients with HNC should employ sEMG technology, as this sensor type yielded better SNR and overall test-retest reliability. Poor MMG test-retest reliability was noted in both healthy and HNC participants and may have been related to differences in sensor application.

Radiation-induced dental caries, prevention and treatment - A systematic review

Treatment of head and neck cancers (HNCs) involves radiotherapy. Patients undergoing radiotherapy for HNCs are prone to dental complications. Radiotherapy to the head and neck region causes xerostomia and salivary gland dysfunction which dramatically increases the risk of dental caries and its sequelae. Radiation therapy (RT) also affects the dental hard tissues increasing their susceptibility to demineralization following RT. Postradiation caries is a rapidly progressing and highly destructive type of dental caries. Radiation-related caries and other dental hard tissue changes can appear within the first 3 months following RT. Hence, every effort should be focused on prevention to manage patients with severe caries. This can be accomplished through good preoperative dental treatment, frequent dental evaluation and treatment after RT (with the exception of extractions), and consistent home care that includes self-applied fluoride. Restorative management of radiation caries can be challenging. The restorative dentist must consider the altered dental substrate and a hostile oral environment when selecting restorative materials. Radiation-induced changes in enamel and dentine may compromise bonding of adhesive materials. Consequently, glass ionomer cements have proved to be a better alternative to composite resins in irradiated patients. Counseling of patients before and after radiotherapy can be done to make them aware of the complications of radiotherapy and thus can help in preventing them.

Survival and quality of life in oropharyngeal cancer patients treated with primary chemoradiation after salivary gland transfer

Objectives:

Salivary gland transfer surgery can reduce xerostomia in oropharyngeal squamous cell carcinoma patients undergoing primary chemoradiation. A potential drawback of salivary gland transfer is the treatment delay associated with the surgery, and its complications. This study aimed to determine whether the treatment delay affects patient survival and to evaluate patient quality of life after salivary gland transfer.

Methods:

A retrospective analysis of 138 patients (salivary gland transfer group, n = 58; non-salivary gland transfer group, n = 80) was performed. Patient survival was compared between these groups using multivariate analysis. Salivary gland transfer patients were further evaluated for surgical complications and for quality of life using the head and neck module of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire.

Results:

Salivary gland transfer and non-salivary gland transfer patients had comparable baseline clinical characteristics. Salivary gland transfer patients experienced a median treatment delay of 16.5 days before chemoradiation (p = 0.035). Multivariate analysis showed that this did not, however, correspond to a survival disadvantage (p = 0.24 and p = 0.97 for disease-free and disease-specific survival, respectively). A very low complication rate was reported for the salivary gland transfer group (1.7 per cent). Questionnaire scores for the item ‘xerostomia’ were very low in salivary gland transfer patients.

Conclusion:

The treatment delay associated with salivary gland transfer surgery does not negatively affect patient survival. Oropharyngeal squamous cell patients have an excellent quality of life after salivary gland transfer.

JOURNAL CLUB: Scatter Radiation Dose From Digital Screening Mammography Measured in a Representative Patient Population

OBJECTIVE

The purpose of this study was to quantify the amount of scatter radiation received at the skin surface overlying the thyroid gland, salivary gland, lens of the eye, sternum, and uterus during a routine screening digital mammographic examination measured in a representative patient population.

SUBJECTS AND METHODS

The subjects were 207 women without symptoms with varied body mass indexes who underwent annual screening mammography while wearing six optically stimulated luminescence dosimeters placed at the bridge of the nose, right submandibular gland, right and left thyroid lobes, mid sternum, and 2 cm caudal to the umbilicus to assess scatter radiation dose to the skin.

RESULTS

The average scatter radiation doses at the skin surface during digital screening mammography in the representative population of women were as follows: overlying the right lobe of the thyroid, 0.24 mGy; left lobe of the thyroid, 0.25 mGy; salivary gland, 0.2 mGy; bridge of the nose, 0.025 mGy; sternum, 0.87 mGy; and umbilicus, 0.011 mGy. The scatter radiation doses at the umbilicus and the bridge of the nose were too low to measure with statistical confidence. Scatter radiation dose increased with increasing body mass index and increasing breast compression thickness.

CONCLUSION

Scatter radiation dose at the skin overlying organs of interest is a small fraction of the entrance skin dose to the breast. The low levels of scatter radiation measured do not support delaying clinically indicated mammography during early pregnancy.

Salivary Secretory Disorders, Inducing Drugs, and Clinical Management

BACKGROUND

Salivary secretory disorders can be the result of a wide range of factors. Their prevalence and negative effects on the patient's quality of life oblige the clinician to confront the issue.

AIM

To review the salivary secretory disorders, inducing drugs and their clinical management.

METHODS

In this article, a literature search of these dysfunctions was conducted with the assistance of a research librarian in the MEDLINE/PubMed Database.

RESULTS

Xerostomia, or dry mouth syndrome, can be caused by medication, systemic diseases such as Sjögren's Syndrome, glandular pathologies, and radiotherapy of the head and neck. Treatment of dry mouth is aimed at both minimizing its symptoms and preventing oral complications with the employment of sialogogues and topical acting substances. Sialorrhea and drooling, are mainly due to medication or neurological systemic disease. There are various therapeutic, pharmacologic, and surgical alternatives for its management. The pharmacology of most of the substances employed for the treatment of salivary disorders is well-known. Nevertheless, in some cases a significant improvement in salivary function has not been observed after their administration.

CONCLUSION

At present, there are numerous frequently prescribed drugs whose unwanted effects include some kind of salivary disorder. In addition, the differing pathologic mechanisms, and the great variety of existing treatments hinder the clinical management of these patients. The authors have designed an algorithm to facilitate the decision making process when physicians, oral surgeons, or dentists face these salivary dysfunctions.

Submandibular Gland Transfer for the Prevention of Postradiation Xerostomia in Patients with Head and Neck Cancer: A Systematic Review and Meta-Analysis

<b><i>Background:</i></b> Submandibular gland transfer has been widely used to prevent postradiation xerostomia in head-and-neck cancers. However, there are still some controversies. <b><i>Methods:</i></b> Six databases were searched, data extraction was performed and the risk of bias was assessed by 2 reviewers independently. The meta-analysis was performed using Review Manager, version 5.2. <b><i>Results:</i></b> A total of 7 trials (12 articles) and 369 participants were included. <b><i>Conclusions:</i></b> The present clinical evidence suggests that submandibular gland transfer might be highly effective to prevent postradiation xerostomia in head-and-neck cancers without serious adverse events. However, more randomized controlled trials are still needed to confirm this conclusion.

Clinical observation of submandibular gland transfer for the prevention of xerostomia after radiotherapy for nasopharyngeal carcinoma: a prospective randomized controlled study of 32 cases

BACKGROUND

The aim of this study was to evaluate the clinical efficacy of submandibular gland transfer for the prevention of xerostomia after radiotherapy for nasopharyngeal carcinoma.

METHODS

Using the randomized controlled clinical research method, 65 patients with nasopharyngeal carcinoma were randomly divided into an experimental group consisting of 32 patients and a control group consisting of 33 patients. The submandibular glands were averted to the submental region in 32 patients with nasopharyngeal carcinoma before they received conventional radiotherapy; a lead block was used to shield the submental region during therapy. Prior to radiotherapy, the function of the submandibular glands was assessed using imaging. Submandibular gland function was measured using 99mTc radionuclide scanning at 60 months after radiotherapy. The data in the questionnaire regarding the degree of xerostomia were investigated and saliva secretion was measured at 3, 6, 12, and 60 months after radiotherapy. In addition, the 5-year survival rate was calculated.

RESULTS

After follow-up for 3, 6, and 12 months, the incidence of moderate to severe xerostomia was significantly lower in the experimental group than in the control group. The average amount of saliva produced by the experimental and control groups was 1.60 g and 0.68 g, respectively (P<0.001). After follow-up for 60 months, the uptake and secretion functions of the submandibular glands in the experimental group were found to be significantly higher than in the control group (P<0.001 and P<0.001, respectively). The incidence of moderate or severe xerostomia was significantly lower than in the control group (15.4% and 76.9%, respectively; P<0.001). The 5-year survival rates of the experimental group and the control group were 81.3% and 78.8%, respectively, and there was no significant difference between the two groups (P=0.806).

CONCLUSIONS

After a 5 year follow-up period involving 32 patients who had their submandibular glands transferred for the prevention of xerostomia after radiotherapy for nasopharyngeal carcinoma, we found that clinical efficacy was good. This approach could improve the quality of life of nasopharyngeal carcinoma patients after radiotherapy and would not affect long-term treatment efficacy.

Management of radiotherapy-induced salivary hypofunction and consequent xerostomia in patients with oral or head and neck cancer: meta-analysis and literature review

OBJECTIVE

To analyze the efficacy of various treatment options for radiation-induced hyposalivation in patients with head and neck cancer.

STUDY DESIGN

A literature review and meta-analysis was performed on all appropriate literature identified via MEDLINE/PubMed.

RESULTS

Fourteen articles were identified that met inclusion criteria for review, and 8 articles qualified for inclusion in the meta-analysis. The available literature addressed both objective and subjective responses of hyposalivation, xerostomia, or both to cholinergic agonists (such as pilocarpine and cevimeline), salivary substitutes, hyperbaric oxygen, and acupuncture.

CONCLUSIONS

This analysis indicated that cholinergic agonists were more effective in treating radiation-induced hyposalivation compared with salivary substitutes, hyperbaric oxygen, and acupuncture. However, other treatment modalities, such as salivary substitutes and hyperbaric oxygen, were also found to subjectively improve patients' perception of xerostomia.

Cost-effectiveness landscape analysis of treatments addressing xerostomia in patients receiving head and neck radiation therapy

Head and neck (H&N) radiation therapy (RT) can induce irreversible damage to the salivary glands thereby causing long-term xerostomia or dry mouth in 68%-85% of the patients. Not only does xerostomia significantly impair patients' quality-of-life (QOL) but it also has important medical sequelae, incurring high medical and dental costs. In this article, we review various measures to assess xerostomia and evaluate current and emerging solutions to address this condition in H&N cancer patients. These solutions typically seek to accomplish 1 of the 4 objectives: (1) to protect the salivary glands during RT, (2) to stimulate the remaining gland function, (3) to treat the symptoms of xerostomia, or (4) to regenerate the salivary glands. For each treatment, we assess its mechanisms of action, efficacy, safety, clinical utilization, and cost. We conclude that intensity-modulated radiation therapy is both the most widely used prevention approach and the most cost-effective existing solution and we highlight novel and promising techniques on the cost-effectiveness landscape.

Neck metastases in oropharyngeal cancer: Necessity and extent of bilateral treatment

BACKGROUND

Bilateral neck treatment in oropharyngeal squamous cell carcinoma (OPSCC) is controversial. This study determined the rate of bilateral neck metastases in OPSCC and formulated a neck treatment algorithrm for OPSCC.

METHODS

In all, 212 consecutive patients with OPSCC underwent ipsilateral level I-V and contralateral I-III or I-V neck dissections. Pathology results were used to identify factors predicting bilateral neck metastases.

RESULTS

A total of 171 patients (81%) had ipsilateral and 41 patients (24%) bilateral neck metastases. Multivariate logistic regression found cT4 and ≥cN2a significantly associated with contralateral neck metastases (p < .05). However, tumor site was not predictive (p > .05). High-risk pathology features predicted contralateral neck disease (p < .05). cN0 and cN1 necks were unlikely to harbor disease in level V (<5%). Both 2- and 5-year contralateral neck recurrence rates were 1% and 2%.

CONCLUSIONS

Bilateral neck disease in OPSCC is more common than once thought. Patients with OPSCC with cT4 or cN2a+ would benefit from bilateral neck treatment. Posttreatment high-risk features should guide treatment escalation.

A phase II study of submandibular gland transfer prior to radiation for prevention of radiation-induced xerostomia in head-and-neck cancer (RTOG 0244)

PURPOSE

We report the results of a phase II study to determine the reproducibility of a submandibular salivary gland transfer (SGT) surgical technique for prevention of radiation (XRT)-induced xerostomia in a multi-institutional setting and to assess severity of xerostomia.

METHODS AND MATERIALS

Eligible patients had surgery for primary, neck dissection, and SGT, followed by XRT, during which the transferred salivary gland was shielded. Intensity modulated radiation therapy, amifostine, and pilocarpine were not allowed, but postoperative chemotherapy was allowed. Each operation was reviewed by 2 reviewers and radiation by 1 reviewer. If 13 or more (of 43) were "not per protocol," then the technique would be considered not reproducible as per study design. The secondary endpoint was the rate of acute xerostomia, grade 2 or higher, and a rate of ≤ 51% was acceptable.

RESULTS

Forty-four of the total 49 patients were analyzable: male (81.8%), oropharynx (63.6%), stage IV (61.4%), median age 56.5 years. SGT was "per protocol" or within acceptable variation in 34 patients (77.3%) and XRT in 79.5%. Nine patients (20.9%) developed grade 2 acute xerostomia; 2 had grade 0-1 xerostomia (4.7%) but started on amifostine/pilocarpine. Treatment for these 11 patients (25.6%) was considered a failure for the xerostomia endpoint. Thirteen patients died; median follow-up for 31 surviving patients was 2.9 years. Two-year overall and disease-free survival rates were 76.4% and 71.7%, respectively.

CONCLUSIONS

The technique of submandibular SGT is reproducible in a multicenter setting. Seventy-four percent of patients were prevented from XRT-induced acute xerostomia.

Caries and periodontal disease in cancer survivors

DATA SOURCES

PubMed and EMBASE were searched for articles published between 1 January 1990 and 31 December 2008.

STUDY SELECTION

Eligible studies were those that included dental caries and periodontal disease and pre-cancer dental clearance protocols in cancer patients undergoing head and neck radiotherapy, chemotherapy or combined treatment modalities. Rather than any study inclusion criteria this review had a number of exclusion criteria instead: systematic and non-systematic reviews; microbiology studies; growth and development studies; organ transplant studies; studies eliciting dental complications through questionnaires, studies reporting data from previous publications; phase I and II studies; opinion papers and case reports; articles published before 1990. All reports also had to be in English.

DATA EXTRACTION AND SYNTHESIS

Each article was reviewed by two authors independently with pilot-tested data collection forms. No quality assessment was pre-specified.

RESULTS

Sixty-four articles were included. Forty-six of these were observational (24 cohort, eight case control, 14 cross-sectional), and 18 were interventional studies. It is unclear how many participants this included. A weighted prevalence of caries was reported but it is unclear how the weighting was calculated. Overall the weighted prevalence was 28.1%. The overall DMFT for patients who were post-antineoplastic therapy was 9.19 (SD, 7.98; n=457). The overall plaque index for patients who were post-antineoplastic therapy was 1.38 (SD, 0.25; n=189).

CONCLUSIONS

Patients who were post-radiotherapy had the highest DMFT compared to those who were post-chemotherapy and healthy controls.

Submandibular salivary gland transfer for the prevention of radiation-induced xerostomia in patients with nasopharyngeal carcinoma: 5-Year outcomes

BACKGROUND

Our aim in this study was to investigate the value of the submandibular salivary gland transfer procedure in prevention of radiation-induced xerostomia in patients with nasopharyngeal carcinoma (NPC).

METHODS

In all, there were 70 patients, consisting of a test group (36 patients) and a control group (34 patients) in a nonrandomized fashion. In the test group, the submandibular salivary gland was transferred to submental space before radiotherapy (XRT) and shielded. Salivary gland functions were evaluated by the amount of saliva and a quality of life questionnaire before and after XRT and 3 and 60 months after XRT.

RESULTS

At 5 years, the trapping and excretion functions of salivary gland were significantly better in the test group (p = .000 and p = .000). The mean weight of saliva after XRT was heavier (1.65 g vs 0.73 g, p = .000), and the incidence of xerostomia was lower in the test group, with no difference in 5-year survival and neck nodal recurrence between the 2 groups.

CONCLUSIONS

Salivary gland transfer procedure prevents XRT-induced xerostomia and improves quality of life of patients with NPC.

Submandibular salivary gland transfer: a pitfall in head and neck imaging with F-18 FDG PET/CT

Xerostomia is a significant morbidity of radiation treatment in the management of head and neck cancers. To preserve salivary function, a surgical technique has been developed that involves the transfer of one submandibular gland to the ipsilateral submental space, where it can be shielded during radiation therapy. F-18 FDG PET/CT imaging characteristics of recently or remotely transferred submandibular glands have not been previously described in the literature. We report 2 cases of patients with surgically transferred submandibular glands, which highlight a potential pitfall in the interpretation of PET/CT of the head and neck region in oncologic patients.

Treatment planning constraints to avoid xerostomia in head-and-neck radiotherapy: an independent test of QUANTEC criteria using a prospectively collected dataset

PURPOSE

The severe reduction of salivary function (xerostomia) is a common complication after radiation therapy for head-and-neck cancer. Consequently, guidelines to ensure adequate function based on parotid gland tolerance dose-volume parameters have been suggested by the QUANTEC group and by Ortholan et al. We perform a validation test of these guidelines against a prospectively collected dataset and compared with a previously published dataset.

METHODS AND MATERIALS

Whole-mouth stimulated salivary flow data from 66 head-and-neck cancer patients treated with radiotherapy at the British Columbia Cancer Agency (BCCA) were measured, and treatment planning data were abstracted. Flow measurements were collected from 50 patients at 3 months, and 60 patients at 12-month follow-up. Previously published data from a second institution, Washington University in St. Louis (WUSTL), were used for comparison. A logistic model was used to describe the incidence of Grade 4 xerostomia as a function of the mean dose of the spared parotid gland. The rate of correctly predicting the lack of xerostomia (negative predictive value [NPV]) was computed for both the QUANTEC constraints and Ortholan et al. recommendation to constrain the total volume of both glands receiving more than 40 Gy to less than 33%.

RESULTS

Both datasets showed a rate of xerostomia of less than 20% when the mean dose to the least-irradiated parotid gland is kept to less than 20 Gy. Logistic model parameters for the incidence of xerostomia at 12 months after therapy, based on the least-irradiated gland, were D(50) = 32.4 Gy and and γ = 0.97. NPVs for QUANTEC guideline were 94% (BCCA data), and 90% (WUSTL data). For Ortholan et al. guideline NPVs were 85% (BCCA) and 86% (WUSTL).

CONCLUSION

These data confirm that the QUANTEC guideline effectively avoids xerostomia, and this is somewhat more effective than constraints on the volume receiving more than 40 Gy.

Functional outcomes related to the prevention of radiation-induced xerostomia: oral pilocarpine versus submandibular salivary gland transfer

BACKGROUND

Xerostomia has a devastating impact on oral function and quality of life in patients who receive radiation treatment for head and neck cancer. The purpose of this study was to examine functional outcomes related to 2 saliva-sparing treatments: (1) oral pilocarpine during radiotherapy; or (2) the submandibular salivary gland transfer (SGT) before radiotherapy.

METHODS

Sixty-nine patients were recruited (SGT = 36; pilocarpine = 33). Speech intelligibility, swallowing outcomes, and quality of life were assessed at 4 points in time (pretreatment, and 1 month, 6 months, and 12 months after the pretreatment assessment).

RESULTS

There were no differences between groups in speech outcomes; however, significant between-group differences existed in swallowing and quality of life outcomes. In all cases, patients who received the SGT procedure had better swallowing outcomes and quality of life scores than the patients who received oral pilocarpine.

CONCLUSION

The SGT should be the treatment of choice between the 2 treatments offered to prevent xerostomia in the present study.

Radiation-induced xerostomia: objective evaluation of salivary gland injury using MR sialography

BACKGROUND AND PURPOSE

Xerostomia (dry mouth) is one of the serious complications of head and neck irradiation and has a strong influence on a patient's activities of daily living. MR sialography with salivary secretion stimulation provides additional functional information (salivary secretion reserve) and may contribute to the evaluation of the severity of xerostomia and predict the risk of developing a radiation-induced xerostomia. This aim of the study was to analyze MR sialography as an objective tool to evaluate radiation-induced salivary injury.

MATERIALS AND METHODS

MR sialography with salivary secretion stimulation was performed in 16 patients with head and neck malignancy before and after irradiation therapy. Multivariate (stepwise multiple regression) analysis was performed to analyze the nonstimulated and stimulated MR sialography findings and the clinical severity of xerostomia.

RESULTS

Multivariate analysis of the preirradiation study revealed no significant independent variables that could predict the clinical severity of xerostomia. In the postirradiation study, following regression with 2 independent variables (secretion response of the submandibular gland [rSG] and parotid gland visualization on stimulated MR sialography [sPG]) could explain 70% of the cases: xerostomia severity grade = 0.681 + 0.871 x rSG - 0.471 x sPG.

CONCLUSIONS

MR sialography is a useful method for visualization of salivary gland radiation injury and estimation of the severity of radiation-induced xerostomia. Insufficiency of secretion reserve at the irradiated submandibular gland has the strongest influence on xerostomia severity. Our investigation suggests that careful submandibular gland protection may lead to prevention and avoidance of radiation-induced xerostomia.

Management of patients who have undergone head and neck cancer therapy

Patients who undergo treatment for head and neck cancers often suffer from acute or late reactions to therapy. Severity of these oral complications may be based on the location and extent of tumor, as well as the type and extent of treatment. Some complications are transient, whereas others require a lifetime of management secondary to damage that results in permanent dysfunction. Patients who have a history of head and neck cancers are also at an increased risk for recurrences or second malignancies, and therefore require close follow-up. Dental professionals should provide preventive and supportive care, including education and symptom management, for patients experiencing oral complications related to cancer therapy, and should closely monitor patients' level of distress, ability to cope, and treatment response.

Evaluation, prevention and management of radiotherapy-induced xerostomia in head and neck cancer patients

PURPOSE OF REVIEW

As part of the multidisciplinary approach to head and neck cancer patients, radiation therapy plays an essential role, improving locoregional control. Radiation therapy-induced xerostomia is a late side-effect that increases the risk for developing dental caries and compromises oral mucosal integrity, resulting in oral pain, loss of taste, difficulties with swallowing and chewing, sleep disorders and worse quality of life. This review focuses on evaluation, prevention and management of radiation therapy-induced xerostomia.

RECENT FINDINGS

In terms of xerostomia prevention, some clinical trials evaluating amifostine and intensity-modulated radiation therapy have shown positive results. Pilocarpine is a useful agent as a treatment of radiation-induced xerostomia in head and neck cancer patients.

SUMMARY

Despite some advances in radiation therapy-induced xerostomia prevention, its treatment is an area in which advances are urgently needed.

Sparing the parotid glands and surgically transferred submandibular gland with helical tomotherapy in post-operative radiation of head and neck cancer: a planning study

BACKGROUND AND PURPOSE

To evaluate the feasibility of sparing the parotid glands and surgically transferred submandibular gland (SMG) by intensity modulated radiotherapy (IMRT) in post-operative cases of head and neck cancer (HNC).

MATERIALS AND METHODS

Ten patients (larynx-2, base of tongue-4, tonsil-3, and unknown primary-1; pathologic stages III-IV) who underwent SMG transfers on the side of N0 neck along with definitive surgery were selected for this study. IMRT planning was done retrospectively using helical tomotherapy approach. Planning objective was to deliver 60 Gy to PTV1 and 54 Gy to PTV2 while maintaining the mean dose to the total parotid volume (TPV) and SMG less than 26 Gy.

RESULTS

The mean dose (+/-SD) to the TPV and SMG were 25+/-0.6 Gy and 23+/-1.9 Gy, respectively. The D(95) for PTV1 and PTV2 were 59.9+/-0.1 Gy and 54.9+/-0.3 Gy, respectively, satisfying our planning goal for PTV coverage. The D(99) for PTV1 and PTV2 were 58.2+/-0.7 Gy and 49.5+/-2.2 Gy, respectively, showing that sparing the salivary glands did not result in underdosing of the PTVs.

CONCLUSIONS

By combining the gland transfer and IMRT, the mean dose to TPV and transferred SMG could be reduced to less than 26 Gy in post-operative patients of HNC.