Xerostomia Scores Research Articles

Secondary doses to healthy tissues during proton therapy treatments: influence of irradiation parameters

Secondary doses to healthy tissues during proton therapy treatments: influence of irradiation parameters

Sublingual Buprenorphine and Dental Problems

Sublingual Buprenorphine and Dental Problems

Dose–response analysis of parotid gland function: What is the best measure of xerostomia?

PurposeTo describe the dose–response relationships for the different measures of salivary gland recovery following radical radiotherapy for locally advanced head and neck squamous cell cancers (LA-HNSCC). Methods and materialsDosimetric analysis of data from the PARSPORT trial, a Phase III study of conventional RT (RT) and intensity modulated radiotherapy (IMRT) for LA-HNSCC was undertaken to determine the relationship between parotid gland mean dose and toxicity endpoints: high-grade subjective and objective xerostomia and xerostomia-related quality of life scores. LKB-NTCP parameters (TD50, m and n) were generated and tolerance doses (D50) reported using non-linear logistic regression analysis. ResultsData were available on 63 patients from the PARSPORT trial. Parotid saliva flow rate provided the strongest association between mean dose and recovery, D50=23.4Gy (20.6–26.2) and k=3.2 (1.9–4.5), R2=0.85. Corresponding LKB parameters were TD50=26.3Gy (95% CI: 24.0–30.1), m=0.25 (0.18–1.0 and n=1). LENTSOMA subjective xerostomia also demonstrated a strong association D50=33.3Gy (26.7–39.8), k=2.8 (91.4–4.4), R2=0.77). ConclusionWe recommend using the LENT SOMA subjective xerostomia score to predict recovery of salivation due to its strong association with dosimetry and ease of recording.

Volume and dosimetric changes and initial clinical experience of a two-step adaptive intensity modulated radiation therapy (IMRT) scheme for head and neck cancer

PurposeThe aim of this study was to show the benefit of a two-step intensity modulated radiotherapy (IMRT) method by examining geometric and dosimetric changes. Material and MethodsTwenty patients with pharyngeal cancers treated with two-step IMRT combined with chemotherapy were included. Treatment-planning CT was done twice before IMRT (CT-1) and at the third or fourth week of IMRT for boost IMRT (CT-2). Transferred plans recalculated initial plan on CT-2 were compared with the initial plans on CT-1. Dose parameters were calculated for a total dose of 70Gy for each plan. ResultsThe volumes of primary tumors and parotid glands on CT-2 regressed significantly. Parotid glands shifted medially an average of 4.2mm on CT-2. The mean doses of the parotid glands in the initial and transferred plans were 25.2Gy and 30.5Gy, respectively. D2 (dose to 2% of the volume) doses of the spinal cord were 37.1Gy and 39.2Gy per 70Gy, respectively. Of 15 patients in whom xerostomia scores could be evaluated 1–2years after IMRT, no patient complained of grade 2 or more xerostomia. ConclusionsThis two-step IMRT method as an adaptive RT scheme could adapt to changes in body contour, target volumes and risk organs during IMRT.

Study on the Clinical Significance and Related Factors of Thirst and Xerostomia in Maintenance Hemodialysis Patients

Aims: To analyse the clinical significance and related factors of thirst and xerostomia and to find methods to alleviate thirst and xerostomia in maintenance hemodialysis (MHD) patients. Methods: Forty-two MHD patients were included for observational study and eleven patients were enrolled for crossover trial. Thirst was assessed by 100-mm visual analog scales (VAS) and dialysis thirst inventory (DTI). Meanwhile, xerostomia was assessed by VAS and xerostomia inventory (XI). Depression, kidney disease quality of life (KDQOL), salivary flow rates and inter dialytic weight gain (IDWG) were measured. Data were analyzed by ANOVA and correlation coefficient was used to assess the correlations between continuous variables. The results of crossover trial were investigated by two-sample T-tests. Results: Strong positive correlations among DTI, VAS thirst score, XI and VAS xerostomia score were found (P=0.000). Daily IDWG was positively correlated with VAS thirst score (r=0.315, P=0.042) and DTI(r=0.391, P=0.010). UWS (unstimulated whole saliva) was negatively correlated with VAS xerostomia score (r=-0.308, P=0.048). Residual urine output was negatively correlated with DTI (r=-0.402, P=0.008), VAS xerostomia score (r=-0.461, P=0.002) and XI (r=-0.403, P=0.008). In the crossover trial, DTI, XI, IDWG2d, IDWG3d, VAS thirst and xerostomia score were significantly reduced by the use of chewing gum (P=0.000, 0.001, 0.009, 0.017, 0.038, 0.001). The VAS thirst score, DTI and IDWG3d were significantly reduced by receiveing straw (P=0.016, 0.003, 0.049). Conclusion: Thirst and xerostomia might affect the quality of life in MHD patients. Both chewing gum and straw could decrease thirst and IDWG.

Metabolic Imaging Biomarkers of Postradiotherapy Xerostomia

Xerostomia is a major complication of head and neck radiotherapy (RT). Available xerostomia measures remain flawed. [(18)F]fluorodeoxyglucose-labeled positron emission tomography-computed tomography (FDG-PET-CT) is routinely used for staging and response assessment of head and neck cancer. We investigated quantitative measurement of parotid gland FDG uptake as a potential biomarker for post-RT xerostomia. Ninety-eight locally advanced head and neck cancer patients receiving definitive RT underwent baseline and post-RT FDG-PET-CT on a prospective imaging trial. A separate validation cohort of 14 patients underwent identical imaging while prospectively enrolled in a second trial collecting sialometry and patient-reported outcomes. Radiation dose and pre- and post-RT standard uptake values (SUVs) for all voxels contained within parotid gland ROI were deformably registered. Average whole-gland or voxel-by-voxel models incorporating parotid D(Met) (defined as the pretreatment parotid SUV weighted by dose) accurately predicted posttreatment changes in parotid FDG uptake (e.g., fractional parotid SUV). Fractional loss of parotid FDG uptake closely paralleled early parotid toxicity defined by posttreatment salivary output (p < 0.01) and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer xerostomia scores (p < 0.01). In this pilot series, loss of parotid FDG uptake was strongly associated with acute clinical post-RT parotid toxicity. D(Met) may potentially be used to guide function-sparing treatment planning. Prospective validation of FDG-PET-CT as a convenient, quantifiable imaging biomarker of parotid function is warranted and ongoing.

Xerostomia after radiotherapy and its effect on quality of life in head and neck cancer patients.

Xerostomia is one of the one complications following radiotherapy that can affect quality of life (QoL). This study aims to assess the severity of xerostomia in patients with head and neck cancers after radiotherapy and its effect on QoL. In this longitudinal prospective study, the severity of xerostomia and related QoL were was assessed in 63 head and neck cancer patients who referred to the Radiotherapy Ward. Patients completed a xerostomia questionnaire (XQ) at the beginning, and 2, 4, and 6 weeks after treatment over a period of 6 months. Additionally, unstimulated saliva was collected using the spitting method at all 4 visits. QoL significantly worsened with increased time (P = 0.0001); meanwhile, the severity of xerostomia increased significantly (P = 0.0001). However, there was no significant change in the amount of saliva at these 4 time points (P = 0.23). Regression analysis showed that with each milliliter decrease in saliva secretion, the QoL score decreased 2.25%. With one score increase in xerostomia, from the QoL mean score there was a 1.65% decrease. The decrease in saliva and xerostomia that resulted from radiotherapy plays an important role in worsening QoL among patients who undergo radiotherapy for head and neck cancers. Although the amount of saliva has a significant association with QoL, the xerostomia score which shows subjects' general feeling also independently impacts QoL. In future studies, we recommend patient assessments for periods longer than 6 months.

Reducing Xerostomia After Chemo-IMRT for Head-and-Neck Cancer: Beyond Sparing the Parotid Glands

To assess whether, in addition to sparing the parotid glands (PGs), xerostomia after chemotherapy plus intensity-modulated radiotherapy (chemo-IMRT) for head-and-neck cancer is affected by reducing the dose to the other salivary glands. In a prospective study, 78 patients with Stage III-IV oropharynx/nasopharynx cancer underwent chemo-IMRT, with the aim of sparing the parts of the bilateral PGs, oral cavity (OC) containing the minor salivary glands, and contralateral submandibular gland (SMG) outside the target (when contralateral level I was not a target). Before therapy and periodically for 24 months, validated patient-reported xerostomia questionnaire (XQ) scores and observer-graded xerostomia scores were recorded. Also, the stimulated and unstimulated saliva was measured selectively from each of the PGs and SMGs. The mean OC doses served as surrogates of minor salivary gland dysfunction. Regression models assessed the XQ and observer-graded xerostomia predictors. Statistically significant predictors of the XQ score on univariate analysis included the OC, PG, and SMG mean doses and the baseline XQ score, time since RT, and both stimulated and unstimulated PG saliva flow rates. Similar factors were statistically significant predictors of observer-graded xerostomia. The OC, PG, and SMG mean doses were moderately intercorrelated (r = 0.47-0.55). On multivariate analyses, after adjusting for the PG and SMG doses, the OC mean dose (p < .0001), interval from RT (p < .0001), and stimulated PG saliva (p < .0025) were significant predictors of the XQ scores and the OC mean dose and time for observer-graded xerostomia. Although scatter plots showed no thresholds, an OC mean dose of <40 Gy and contralateral SMG mean dose of <50 Gy were each associated with low patient-reported and observer-rated xerostomia at almost all post-therapy points. The PG, SMG, and OC mean doses were significant predictors of both patient-reported and observer-rated xerostomia after chemo-IMRT, with OC doses remaining significant after adjusting for the PG and SMG doses. These results support efforts to spare all the salivary glands by IMRT, beyond the PGs alone.

A Two-step Intensity-modulated Radiation Therapy Method for Nasopharyngeal Cancer: The Kinki University Experience

The aim of this study was to analyze the clinical results of our adaptive radiation therapy scheme of a two-step intensity-modulated radiotherapy (IMRT) method for nasopharyngeal cancer (NPC) at Kinki University Hospital. Between 2000 and 2007, 35 patients with Stage I-IVB NPC treated by IMRT were included. For all patients, treatment-planning computed tomography was done twice before and during IMRT to a total dose of 60-70 Gy/28-35 fractions (median 68 Gy). Chemotherapy (cisplatin 80 mg/m(2)/3 weeks x 1-3 courses) was given concurrently with IMRT for 31 patients. The 3- and 5-year overall survival rates for the 31 patients treated with concurrent chemotherapy were 88% and 83%, respectively. The 3- and 5-year loco-regional control rates for the 31 patients were 93% and 87%, respectively. Planning target volume delineation for the primary site or involved nodes was insufficient for three early cases, resulting in marginal recurrence in the three patients (9%). Except for one patient with early death, xerostomia scores at 1-2 years were: Grade 0, 11; Grade 1, 17; Grade 2, 5; Grade 3, 1. Excellent overall survival and loco-regional control rates were obtained by a two-step IMRT method with concurrent chemotherapy for NPC, although marginal recurrence was noted in some early cases.

Bilateral Superficial Parotid Gland Sparing IMRT Produces Similar Long-term Xerostomia Scores when Compared to Unilateral Parotid Sparing IMRT in Midline Head and Neck Squamous Cell Cancers (HNSCC)

Bilateral Superficial Parotid Gland Sparing IMRT Produces Similar Long-term Xerostomia Scores when Compared to Unilateral Parotid Sparing IMRT in Midline Head and Neck Squamous Cell Cancers (HNSCC)

First results of a phase III multicenter randomized controlled trial of intensity modulated (IMRT) versus conventional radiotherapy (RT) in head and neck cancer (PARSPORT: ISRCTN48243537; CRUK/03/005)

LBA6006 Background: Xerostomia is the most common late toxicity of RT to the head and neck. IMRT dose distributions reduce the dose delivered to parotid gland. PARSPORT investigated the role of IMRT in reducing xerostomia in patients with head and neck cancer. Methods: The PARSPORT trial compared two radiotherapy delivery methods in the treatment of patients with pharyngeal tumors (T1–4, N0–3, M0). Patients received 65Gy in 30 fractions over 6 weeks delivered using either CT planned parallel opposed lateral fields or parotid-sparing IMRT. Stratification was by site of tumor and center. The primary endpoint was incidence of LENT-SOMA ≥G2 xerostomia one year after treatment. Secondary endpoints included acute toxicities (CTCAE v3) and other late RTOG and LENT-SOMA radiation toxicities. Proportions of patients with ≥G2 toxicity were compared using exact tests. For secondary endpoints a significance level of 1% was used. Results: 94 patients (47 RT; 47 IMRT) were randomized between 2003 and 2007 from six UK centers. 80 patients had oropharyngeal tumors and 14 hypopharyngeal. Radiotherapy was given as primary treatment in 71 patients and post-operatively in 23. 22 patients had AJCC stage I/II disease. Median follow-up was 31.9 months (IQR: 26.6 –38.8). Twelve month LENT-SOMA ≥G2 xerostomia scores were observed in 74% (25/34) of RT and 40% (15/38) of IMRT patients (p=0.005). Corresponding values at 18 months were 71% (15/21) and 29% (9/31) (p=0.004). On the RTOG scale, 12 month ≥G2 xerostomia was reported in 64% (21/33) RT vs 41% (15/37) IMRT patients (p=0.06). The 18 month incidence was 81% 17/21 RT vs 20% (6/30) IMRT (p&lt;0.001). Acute radiotherapy related ≥G2 fatigue was more prevalent in the IMRT group (76% vs 41% p=0.001). No differences in acute mucositis or pain scores were seen. At 12 months, no statistically significant differences were seen in other late toxicities. No differences were observed between overall survival and locoregional control rates. Conclusions: Sparing the salivary glands through use of IMRT significantly reduces the incidence of xerostomia in patients with pharyngeal tumors. [Table: see text]

First results of a phase III multicenter randomized controlled trial of intensity modulated (IMRT) versus conventional radiotherapy (RT) in head and neck cancer (PARSPORT: ISRCTN48243537; CRUK/03/005)

LBA6006 Background: Xerostomia is the most common late toxicity of RT to the head and neck. IMRT dose distributions reduce the dose delivered to parotid gland. PARSPORT investigated the role of IMRT in reducing xerostomia in patients with head and neck cancer. Methods: The PARSPORT trial compared two radiotherapy delivery methods in the treatment of patients with pharyngeal tumors (T1–4, N0–3, M0). Patients received 65Gy in 30 fractions over 6 weeks delivered using either CT planned parallel opposed lateral fields or parotid-sparing IMRT. Stratification was by site of tumor and center. The primary endpoint was incidence of LENT-SOMA ≥G2 xerostomia one year after treatment. Secondary endpoints included acute toxicities (CTCAE v3) and other late RTOG and LENT-SOMA radiation toxicities. Proportions of patients with ≥G2 toxicity were compared using exact tests. For secondary endpoints a significance level of 1% was used. Results: 94 patients (47 RT; 47 IMRT) were randomized between 2003 and 2007 from six UK centers. 80 patients had oropharyngeal tumors and 14 hypopharyngeal. Radiotherapy was given as primary treatment in 71 patients and post-operatively in 23. 22 patients had AJCC stage I/II disease. Median follow-up was 31.9 months (IQR: 26.6 –38.8). Twelve month LENT-SOMA ≥G2 xerostomia scores were observed in 74% (25/34) of RT and 40% (15/38) of IMRT patients (p=0.005). Corresponding values at 18 months were 71% (15/21) and 29% (9/31) (p=0.004). On the RTOG scale, 12 month ≥G2 xerostomia was reported in 64% (21/33) RT vs 41% (15/37) IMRT patients (p=0.06). The 18 month incidence was 81% 17/21 RT vs 20% (6/30) IMRT (p<0.001). Acute radiotherapy related ≥G2 fatigue was more prevalent in the IMRT group (76% vs 41% p=0.001). No differences in acute mucositis or pain scores were seen. At 12 months, no statistically significant differences were seen in other late toxicities. No differences were observed between overall survival and locoregional control rates. Conclusions: Sparing the salivary glands through use of IMRT significantly reduces the incidence of xerostomia in patients with pharyngeal tumors. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Elekta, Varian Medical Systems

Parotid gland sparing IMRT for head and neck cancer improves xerostomia related quality of life

Background and purposeTo assess the impact of intensity modulated radiotherapy (IMRT) versus conventional radiation on late xerostomia and Quality of Life aspects in head and neck cancer patients.Patients and nethodsQuestionnaires on xerostomia in rest and during meals were sent to all patients treated between January 1999 and December 2003 with a T1-4, N0-2 M0 head and neck cancer, with parotid gland sparing IMRT or conventional bilateral neck irradiation to a dose of at least 60 Gy, who were progression free and had no disseminated disease (n = 192). Overall response was 85% (n = 163); 97% in the IMRT group (n = 75) and 77% in the control group (n = 88) the median follow-up was 2.6 years. The prevalence of complaints was compared between the two groups, correcting for all relevant factors at multivariate ordinal regression analysis.ResultsPatients treated with IMRT reported significantly less difficulty transporting and swallowing their food and needed less water for a dry mouth during day, night and meals. They also experienced fewer problems with speech and eating in public. Laryngeal cancer patients in general had fewer complaints than oropharynx cancer patients but both groups benefited from IMRT. Within the IMRT group the xerostomia scores were better for those patients with a mean parotid dose to the "spared" parotid below 26 Gy.ConclusionParotid gland sparing IMRT for head and neck cancer patients improves xerostomia related quality of life compared to conventional radiation both in rest and during meals. Laryngeal cancer patients had fewer complaints but benefited equally compared to oropharyngeal cancer patients from IMRT.

Assessment of Xerostomia and Its Impact on Quality of Life in Head and Neck Cancer Patients Undergoing Radiotherapy, and Validation of the Taiwanese Version of the Xerostomia Questionnaire

The purposes of this study were to (a) explore the impact of xerostomia and saliva flow on quality of life and (b) validate the Taiwanese version of the Xerostomia Questionnaire (XQ) for patients undergoing radiotherapy (RT) for head and neck cancer in Taiwan. This was a prospective longitudinal study. Instruments consisted of the Xerostomia Questionnaire-Taiwan version (XQ-T) and the Medical Outcomes Study Short Form-36 Taiwan Version. Salivary output was measured by collecting unstimulated whole saliva. The questionnaires and measurements of salivary output were completed before RT was initiated and at two, four, six, and eight weeks after RT had started. Changes in xerostomia scores, quality of life, saliva flow, and predictors of quality of life over time were examined by using general estimating equations. The XQ-T is the first xerostomia measurement instrument developed for use with Taiwanese cancer patients and demonstrated excellent reliability and validity. Saliva flow was significantly correlated with XQ-T scores at two, four, six, and eight weeks after RT had started, but not before RT had begun. Saliva flow and quality-of-life scores significantly diminished and xerostomia scores significantly increased over the eight-week period. Saliva flow and XQ-T scores significantly predicted quality of life, after adjusting for the maturation effect. The results of this study show that the XQ-T is the first xerostomia measurement instrument to be developed for Taiwanese cancer patients and demonstrates excellent reliability and validity.

Increased thirst and drinking in Huntington's disease and the R6/2 mouse

While Huntington's disease (HD) is a condition that primarily involves the basal ganglia, there is evidence to suggest that the hypothalamus is also affected. Because the osmoreceptors regulating thirst are situated in the circumventricular region of the hypothalamus, we were interested in whether altered thirst is a part of the HD phenotype. We used the LABORAS behavioural monitoring system and water consumption to show that drinking behaviour was abnormal in R6/2 mice. By 10 weeks of age, R6/2 mice spent significantly more time drinking and drank a greater volume than their wild-type (WT) littermates. The numbers of immunoreactive vasopressin neurons in the paraventricular nucleus (PVN) of the hypothalamus in R6/2 mice were significantly decreased from 8 weeks of age, suggesting that the change in drinking behaviour may be the result of hypothalamic dysfunction. We gave a xerostomia (dry mouth) questionnaire to HD patients and control subjects, and also measured their urine osmolality and serum vasopressin. The mean total xerostomia score was significantly higher in HD patients than in controls, indicating greater thirst in HD patients. Urine osmolality was unaffected in HD patients up to clinical stage III, and none of the patients had diabetes. However, serum vasopressin was increased, suggesting a dysregulation in the control of hypothalamic vasopressin release. A dry mouth can affect taste, mastication and swallowing, all of which may contribute to the significant weight loss seen in both HD patients and R6/2 mice, as can dehydration. We suggest that increased thirst may be an important and clinically relevant biomarker for the study of disease progression in HD.

Protection of Salivary Function by Concomitant Pilocarpine During Radiotherapy: A Double-Blind, Randomized, Placebo-Controlled Study

To investigate the effect of concomitant administration of pilocarpine during radiotherapy for head-and-neck squamous cell carcinoma (HNSCC) on postradiotherapy xerostomia. A prospective, double blind, placebo-controlled randomized trial including 170 patients with HNSCC was executed to study the protective effect of pilocarpine on radiotherapy-induced parotid gland dysfunction. The primary objective endpoint was parotid flow rate complication probability (PFCP) scored 6 weeks, 6 months, and 12 months after radiotherapy. Secondary endpoints included Late Effects of Normal Tissue/Somatic Objective Management Analytic scale (LENT SOMA) and patient-rated xerostomia scores. For all parotid glands, dose-volume histograms were assessed because the dose distribution in the parotid glands is considered the most important prognostic factor with regard to radiation-induced salivary dysfunction. Although no significant differences in PFCP were found for the two treatments arms, a significant (p = 0.03) reduced loss of parotid flow 1 year after radiotherapy was observed in those patients who received pilocarpine and a mean parotid dose above 40 Gy. The LENT SOMA and patient-rated xerostomia scores showed similar trends toward less dryness-related complaints for the pilocarpine group. Concomitant administration of pilocarpine during radiotherapy did not improve the PFCP or LENT SOMA and patient-rated xerostomia scores. In a subgroup of patients with a mean dose above 40 Gy, pilocarpine administration resulted in sparing of parotid gland function. Therefore, pilocarpine could be provided to patients in whom sufficient sparing of the parotid is not achievable.

The influence of xerostomia after radiotherapy on quality of life

Xerostomia is a common complication of radiotherapy for head and neck cancer because irreparable damage is caused to the salivary glands if they are included in the radiation fields. The aim of the study was to evaluate the degree of xerostomia in survivors of head and neck cancer and to determine its impact on quality of life. A xerostomia questionnaire consisting of three parts (xerostomia score, quality of life survey, and visual analogue scale) was completed by 75 head and neck cancer patients, more than 6 months after radiotherapy and without evidence of disease. The majority of patients (93%) suffered from a dry mouth, and 65% had moderate to severe xerostomia (grade 2 to 3). Both dysphagia (65%) and taste loss (63%) were common, although oral pain was less frequent (33%). The emotional impact of xerostomia was significant, causing worry (64%), tension (61%), or feelings of depression (44%). Furthermore, patients reported problems with talking to (60%) or eating with (54%) other people and to feel restricted in amount and type of food (65%). Quality of life was influenced by T classification, clinical stage, a higher radiation dose or the use of concomitant chemotherapy, but was independent of the interval since the end of radiotherapy. Xerostomia after radiotherapy for head and neck cancer is extremely common and significantly affects quality of life. No recuperation is seen over time, and the use of concomitant chemotherapy significantly increases the oral complications of radiation. These results warrant the continuing efforts put into the development of salivary gland-sparing radiotherapy techniques and effective treatments of radiation-induced xerostomia.

Adjuvant chemotherapy in breast cancer patients induces temporary salivary gland hypofunction

It is an open question if chemotherapy (CT) per se imposes adverse effects on salivary gland function. The aim of the present study was to investigate effects of CT on salivary function in breast cancer patients during and after adjuvant CT. Forty-five breast cancer patients, eligible for adjuvant CT with CEF or CMF (cyclophosphamide, epirubicin or methotrexate, 5-fluorouracil) were followed before, during, six months and one year after CT. Findings were compared to those in a control group of 31 breast cancer patients not receiving CT. Flow rates and compositions of unstimulated and stimulated whole saliva as well as stimulated parotid saliva (UWS, SWS and SPS) were measured. Feeling of oral dryness and saliva-related complaints were registered. UWS and SWS flow rates decreased during CT (p<0.001 and p<0.01). UWS remained lower six months after, but reached baseline level within one year. SPS flow rate was not significantly affected, suggesting that the decrease in whole saliva production is accounted for by decreased acinar saliva formation by the submandibular glands. Twenty patients (44%) suffered from hyposalivation (UWS < or = 0.1 ml/min and/or SWS < or = 0.5 ml/min) during CT. Xerostomia scores rose during CT and stayed elevated one year after treatment. CT also induced compositional changes by slightly increasing salivary sodium and chloride concentrations as well as decreasing inorganic phosphate concentrations in spite of lower or unchanged flow rates, implying that ductal modification mechanisms are affected. UWS and SWS total protein output and UWS secretory IgA output decreased in response to CT. Thus, the results suggest that acinar and ductal cell functions are affected by adjuvant CT. These adverse drug reactions are temporary, as salivary findings generally returned to baseline values within one year following treatment.

Assessment of Salivary Function Change in Nasopharyngeal Carcinoma Treated by Parotid-Sparing Radiotherapy

The purpose of this study was to evaluate function of major salivary glands, subjective xerostomia, and correlation between subjective and objective xerostomia scoring after precision-oriented radiotherapy for nasopharyngeal carcinoma. From 2000 to 2002, 34 patients with histologically proven non-metastatic nasopharyngeal carcinoma received definitive therapy by parotid-sparing radiotherapy, which included intensity-modulated radiotherapy (33 patients>60 Gy), 3D-conformal radiotherapy, and brachytherapy boost. Salivary function was assessed by sialoscintigraphy pre-irradiation and post-irradiation at 1, 6, 12, and 18 months. The salivary stimulated secretion ratio (SSR) was used to evaluate function of submandibular and parotid glands. Subjective and objective xerostomia was monitored by the LENT/SOMA system. The median dose to parotid gland was 34.6 Gy (interquartile range, 32.9-36.5 Gy). The median dose to submandibular gland was 60.5 Gy (interquartile range, 58.1-61.5 Gy). Parotid-gland post-irradiation median SSR at 1 (0.01, P=0.000) and 6 (0.08, P=0.002) months showed significant reduction compared with pre-irradiation data (0.30). After 12 months, parotid-gland median SSR (12 months, 0.22, P = 0.734; 18 months, 0.16, P=0.885) lost significance compared with pre-irradiation data. Submandibular-gland post-irradiation median SSR at 1 (P=0.000), 6 (P=0.000), 12 (P=0.000), and 18 (P=0.000) months all showed significant reduction compared with pre-irradiation data. There were significant correlations between LENT/SOMA subjective and objective xerostomia scores at 6 months (r=0.657, P=0.000), 12 months (r=0.480, P=0.013), and 18 months (r=0.591, P=0.002). With parotid-sparing radiotherapy for nasopharyngeal carcinoma, gland function can recover significantly 12 months after radiotherapy. There were significant rank-order correlations between LENT/SOMA subjective and objective (analytic) grading scores at 6 to 18 months' follow-up.

Three-dimensional conformal radiotherapy for locally advanced (Stage II and worse) head-and-neck cancer: Dosimetric and clinical evaluation

To evaluate the dosimetric parameters of three-dimensional conformal radiotherapy (3D-CRT) in locally advanced head-and-neck tumors (Stage II and above) and the effects on xerostomia. A total of 49 patients with histologically proven squamous cell cancer of the head and neck were consecutively treated with 3D-CRT using a one-point setup technique; 17 had larynx cancer, 12 oropharynx, 12 oral cavity, and 6 nasopharynx cancer; 2 had other sites of cancer. Of the 49 patients, 41 received postoperative RT and 8 definitive treatment. Also, 13 were treated with cisplatin-based chemotherapy before and during RT; in 6 cases, 5-fluorouracil was added. The follow-up time was 484-567 days (median, 530 days). One-point setup can deliver 96% of the prescribed dose to the isocenter, to the whole planning target volume, including all node levels of the neck and without overdosages. The mean dose to the primary planning target volume was 49.54 +/- 4.82 Gy (51.53 +/- 5.47 Gy for larynx cases). The average dose to the contralateral parotid gland was approximately 38 Gy (30 Gy for larynx cases). The maximal dose to the spinal cord was 46 Gy. A Grade 0 Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer xerostomia score corresponded to a mean dose of 30 Gy to one parotid gland. A lower xerostomia score with a lower mean parotid dose and longer follow-up seemed to give rise to a sort of functional recovery phenomenon. Three dimensional-CRT in head-and-neck cancers permits good coverage of the planning target volume with about 10-11 segments and one isocenter. With a mean dose of approximately 30 Gy to the contralateral parotid, we observed no or mild xerostomia.