UNASSIGNED: Chordomas have a high risk of recurrence. Radiotherapy (RT) is required as adjuvant therapy after resection. Sufficient radiation doses for local control (LC) can be achieved using either particle therapy, if this technology is available and feasible, or intensity-modulated radiotherapy.
UNASSIGNED: 57 patients (age, 11.8-81.6 years) with chordomas of the skull base, spine and pelvis who received photon radiotherapy between 1995 and 2017 were enrolled in the study. Patients were treated at the time of initial diagnosis (68.4%) or during recurrence (31.6%). 44 patients received adjuvant radiotherapy and 13 received definitive radiotherapy. The median total dose to the physical target volume was 70 Gy equivalent dose in 2 Gy fractions (EQD2) (range: 54.7-82.5) in 22-36 fractions.
UNASSIGNED: LC was 76.4%, 58.4%, 46.7% and 39.9% and overall survival (OS) was 98.3%, 89%, 76.9% and 47.9% after 1, 3, 5 and 10 years, respectively, with a median follow-up period of 6.5 years (range, 0.5-24.3 years). Age, dose and treatment concept (post-operative or definitive) were significant prognostic factors for OS. Primary treatment, macroscopic tumour at RT and size of the irradiated volume were statistically significant prognostic factors for LC.
UNASSIGNED: Photon treatment is a safe and effective treatment for chordomas if no particle therapy is available. The best results can be achieved against primary tumours if the application of curative doses is possible due to organs at risk in direct proximity. We recommend high-dose radiotherapy, regardless of the resection status, as part of the initial treatment of chordoma, using the high conformal radiation technique if particle therapy is not feasible.

Patients sometimes report phosphene and phantosmia during radiation therapy (RT). However, the detail features and related factors are not well understood. Our prospective study aimed to investigate the characteristics of phantosmias and phosphenes, to identify factors that influence the occurrence, intensity and hedonic (pleasantness/unpleasantness) ratings of such sensations during RT.
We included a total of 106 patients (37 women), who underwent RT in regions of the brain, ear, nose, throat (ENT), and other areas of the body for a duration of 43 ± 5 days. Medical history and treatment parameters were collected in a structured medical interview. Olfactory function was measured using the Sniffin\' Stick Odor Identification Test at baseline. Phantosmia and phosphene were recorded weekly based on a self-report questionnaire.
There were 37% of the patients experiencing phantosmias, 51% experiencing phosphenes, and 29% simultaneously experiencing both sensations. Phosphenes were typically perceived as a flashily blue, white and/or purple light, phantosmias were typically perceived as a chemical-like, metallic or burnt smell. Younger age (F = 7.81, p < 0.01), radiation in the brain region (χ2 = 14.05, p = 0.02), absence of taste problems (χ2 = 10.28, p = 0.01), and proton RT (χ2 = 10.57, p = 0.01) were related to these abnormal sensations. History of chemical/dust exposure predicted lower intensity (B = -1.52, p = 0.02) and lower unpleasantness (B = 0.49, p = 0.03) of phantosmia. In contrast, disease (tumor) duration (B = 0.11, p < 0.01), food allergy (B = 2.77, p < 0.01), and epilepsy (B = -1.50, p = 0.02) influence phosphenes intensity. Analgesics intake predicted a higher pleasantness of the phosphenes (B = 0.47, p < 0.01).
Phantosmias and phosphenes are common during RT. The treatment settings and individual arousal level influence the occurrence, intensity and hedonic of such abnormal sensations. Phantosmias and phosphenes may involve more central neural than peripheral mechanism, and they could be elicited with activation of areas that are not regarded to be part of the olfactory or visual network.

Depending on wavelength and pigmentation, human skin can reflect up to 70% of incident laser light.
We tested the hypothesis that returning (\"recycling\") this diffusely reflected light to the site of laser exposure would increase cutaneous response.
Thirteen adult volunteers with Fitzpatrick skin types I-IV participated in this IRB-approved study. Matched contralateral test sites on the volar forearms were exposed to a pulsed dye laser operated at 585 nm, 450 microseconds pulse duration in a uniform 5 mm circular exposure spot without skin cooling. On one arm, the laser handpiece was fitted with an aluminized hemispherical mirror with a reflectance of 67%. The minimum fluence causing skin purpura, and the purpura lesion diameter were measured.
The mean purpura threshold fluence with the reflector was 3.1 J/cm2 (0.5 SD), and 3.7 J/cm2 without the reflector (0.36 SD) (p < 0.001). The mean laser-induced purpura lesion diameter was approximately 5.3 mm with the reflector and 5.0 mm without the reflector.
Consistent with a theoretical model and in vitro measurements, this human study confirms that \"recycling\" reflected laser light can increase skin response. Potentially, the therapeutic response can also be improved with \"photon recycling.\"

To compare some biological materials in respect to the water and tissue equivalence properties for photon, electron, proton and alpha particle interactions as means of the effective atomic number (Zeff) and electron density (Ne).
A Z-wise interpolation procedure has been adopted for calculation of Zeff using the mass attenuation coefficients for photons and the mass stopping powers for charged particles.
At relatively low energies (100 keV-3 MeV), Zeff and Ne for photons and electrons were found to be constant while they vary much more for protons and alpha particles. In contrast, Zeff and Ne for protons and alpha particles were found to be constant after 3 MeV whereas for photons and electrons they were found to increase with the increasing energy. Also, muscle eq. liquid (with sucrose) have Zeff and Ne values close to the Muscle Skeletal (ICRP) and Muscle Striated (ICRU) within low relative differences below 9%. Muscle eq. liquid (without sucrose) have Zeff and Ne values close to the Muscle Skeletal (ICRP) and Muscle Striated (ICRU) with difference below 10%.
The reported data should be useful in determining best water as well as tissue equivalent materials for photon, electron, proton and alpha particle interactions.

OBJECTIVE: We prospectively evaluated the amino acid analogue positron emission tomography radiotracer anti-3-[(18)F]FACBC compared to ProstaScint® ((111)In-capromab pendetide) single photon emission computerized tomography-computerized tomography to detect recurrent prostate carcinoma.
METHODS: A total of 93 patients met study inclusion criteria who underwent anti-3-[(18)F]FACBC positron emission tomography-computerized tomography plus (111)In-capromab pendetide single photon emission computerized tomography-computerized tomography for suspected recurrent prostate carcinoma within 90 days. Reference standards were applied by a multidisciplinary board. We calculated diagnostic performance for detecting disease.
RESULTS: In the 91 of 93 patients with sufficient data for a consensus on the presence or absence of prostate/bed disease anti-3-[(18)F]FACBC had 90.2% sensitivity, 40.0% specificity, 73.6% accuracy, 75.3% positive predictive value and 66.7% negative predictive value compared to (111)In-capromab pendetide with 67.2%, 56.7%, 63.7%, 75.9% and 45.9%, respectively. In the 70 of 93 patients with a consensus on the presence or absence of extraprostatic disease anti-3-[(18)F]FACBC had 55.0% sensitivity, 96.7% specificity, 72.9% accuracy, 95.7% positive predictive value and 61.7% negative predictive value compared to (111)In-capromab pendetide with 10.0%, 86.7%, 42.9%, 50.0% and 41.9%, respectively. Of 77 index lesions used to prove positivity histological proof was obtained in 74 (96.1%). Anti-3-[(18)F]FACBC identified 14 more positive prostate bed recurrences (55 vs 41) and 18 more patients with extraprostatic involvement (22 vs 4). Anti-3-[(18)F]FACBC positron emission tomography-computerized tomography correctly up-staged 18 of 70 cases (25.7%) in which there was a consensus on the presence or absence of extraprostatic involvement.
CONCLUSIONS: Better diagnostic performance was noted for anti-3-[(18)F]FACBC positron emission tomography-computerized tomography than for (111)In-capromab pendetide single photon emission computerized tomography-computerized tomography for prostate carcinoma recurrence. The former method detected significantly more prostatic and extraprostatic disease.