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1.  Analysis of Factors Influencing the Development of Xerostomia during Intensity-Modulated Radiotherapy 
Factors influencing xerostomia during intensity-modulated radiation therapy (IMRT) were assessed.
A 6-week study of 32 head and neck cancer (HNC) patients was performed. Subjects completed the Xerostomia Inventory (XI) and provided stimulated saliva (SS) at baseline, week two and at end of IMRT. Influence of SS flow rate (SSFR), calcium and mucin 5b (MUC5b) concentrations and radiation dose on xerostomia was determined.
HNC subjects experienced mean SSFR decline of 36% by visit two (N=27; p=0.012) and 57% by visit three (N=20; p=0.0004), Concentrations of calcium and MUC5b increased, but not significantly during IMRT (p>0.05). Xerostomia correlated most with decreasing salivary flow rate as determined by Spearman correlations (p<0.04) and linear mixed models (p<0.0001).
Although IMRT is sparing to the parotid glands, it has an early effect on SSFR and the constituents in saliva in a manner that is associated with the perception of xerostomia.
PMCID: PMC3665637  PMID: 23523462
burning mouth; burning tongue; calcium; gland sparing; head and neck cancer; hyposalivation; intensity modulated radiation therapy; IMRT; irradiation; mucin; MUC5B; saliva; xerostomia
2.  Accuracy of Self-Reported Tobacco Assessments in a Head and Neck Cancer Treatment Population 
Radiotherapy and Oncology  2011;103(1):45-48.
Prospective analysis was performed of self-reported and biochemically confirmed tobacco use in 50 head and neck cancer patients during treatment. With 93.5% compliance to complete weekly self-report and biochemical confirmatory tests, 29.4% of smokers required biochemical assessment for identification. Accuracy increased by 14.9% with weekly vs. baseline self-reported assessments. Data confirm that head and neck cancer patients misrepresent true tobacco use during treatment.
PMCID: PMC3327779  PMID: 22119370
tobacco; smoking; head/neck; radiotherapy; cotinine
3.  Noninvasive diffuse optical monitoring of head and neck tumor blood flow and oxygenation during radiation delivery 
Biomedical Optics Express  2012;3(2):259-272.
This study explored using a novel diffuse correlation spectroscopy (DCS) flow-oximeter to noninvasively monitor blood flow and oxygenation changes in head and neck tumors during radiation delivery. A fiber-optic probe connected to the DCS flow-oximeter was placed on the surface of the radiologically/clinically involved cervical lymph node. The DCS flow-oximeter in the treatment room was remotely operated by a computer in the control room. From the early measurements, abnormal signals were observed when the optical device was placed in close proximity to the radiation beams. Through phantom tests, the artifacts were shown to be caused by scattered x rays and consequentially avoided by moving the optical device away from the x-ray beams. Eleven patients with head and neck tumors were continually measured once a week over a treatment period of seven weeks, although there were some missing data due to the patient related events. Large inter-patient variations in tumor hemodynamic responses were observed during radiation delivery. A significant increase in tumor blood flow was observed at the first week of treatment, which may be a physiologic response to hypoxia created by radiation oxygen consumption. Only small and insignificant changes were found in tumor blood oxygenation, suggesting that oxygen utilizations in tumors during the short period of fractional radiation deliveries were either minimal or balanced by other effects such as blood flow regulation. Further investigations in a large patient population are needed to correlate the individual hemodynamic responses with the clinical outcomes for determining the prognostic value of optical measurements.
PMCID: PMC3269843  PMID: 22312579
(170.0170) Medical optics and biotechnology; (170.3660) Light propagation in tissues; (170.3880) Medical and biological imaging; (170.6480) Spectroscopy, speckle
4.  Influences of tissue absorption and scattering on diffuse correlation spectroscopy blood flow measurements 
Biomedical Optics Express  2011;2(7):1969-1985.
In this study we evaluate the influences of optical property assumptions on near-infrared diffuse correlation spectroscopy (DCS) flow index measurements. The optical properties, absorption coefficient (µa) and reduced scattering coefficient (µs′), are independently varied using liquid phantoms and measured concurrently with the flow index using a hybrid optical system combining a dual-wavelength DCS flow device with a commercial frequency-domain tissue-oximeter. DCS flow indices are calculated at two wavelengths (785 and 830 nm) using measured µa and µs′ or assumed constant µa and µs′. Inaccurate µs′ assumptions resulted in much greater flow index errors than inaccurate µa. Underestimated/overestimated µs′ from −35%/+175% lead to flow index errors of +110%/−80%, whereas underestimated/overestimated µa from −40%/+150% lead to −20%/+40%, regardless of the wavelengths used. Examination of a clinical study involving human head and neck tumors indicates up to +280% flow index errors resulted from inter-patient optical property variations. These findings suggest that studies involving significant µa and µs′ changes should concurrently measure flow index and optical properties for accurate extraction of blood flow information.
PMCID: PMC3130582  PMID: 21750773
(170.0170) Medical optics and biotechnology; (170.3660) Light propagation in tissues; (170.3880) Medical and biological imaging; (170.6480) Spectroscopy, speckle
5.  A Randomized Phase II Trial of High Dose Melatonin and Radiation Therapy for RPA Class 2 Patients with Brain Metastases (RTOG 0119) 
RTOG 0119 was a Phase II randomized trial for RTOG RPA Class 2 patients with brain metastases to determine if high-dose melatonin improves survival over historical controls, and to determine if the time of day melatonin was given affects its toxicity or efficacy.
RTOG RPA class 2 patients with brain metastases were randomized to 20 mg of melatonin given either in the morning (8-9 am) or evening (8-9 pm). All patients received radiation therapy (30 Gy in 10 fractions) in the afternoon. Melatonin was continued until neurological deterioration or death. The primary endpoint was overall survival time. Neurological deterioration as reflected by the Mini-Mental Status Exam was also measured.
Neither of the randomized groups had survival distributions that differed significantly from the historic control of patients treated with whole brain radiotherapy The median survivals of the morning and evening melatonin treatments were 3.4 and 2.8 months while the RTOG historical control is 4.1 months.
High dose melatonin did not show any beneficial effect in this group of patients.
PMCID: PMC2709786  PMID: 17418968
melatonin; brain metastases; chronobiology; randomized trial; survival

Results 1-5 (5)