An Evidence-Based Review of Total Body Irradiation

The purpose of this literature review is to investigate clinical treatment methods of total body irradiation within the context of a clinical department adopting a paediatric cohort with no existing technique. An extensive review of the literature was conducted using PubMed, Science Direct, Google Scholar, and Clinicians Knowledge Network. Articles were limited to nonhelical tomotherapy, nonparticle therapies, and those using hyperfractionated regimes. Total marrow irradiation was excluded because of national treatment and trial limitations. Of the numerous patient positioning methods present within the literature, the most comfortable and reproducible positioning methods for total body irradiation include both supine and the supine and/or prone combination. These positions increased stability and patient comfort during treatment, while also facilitating computed tomography data acquisition at the simulation stage. Ideally, dose calculations should be performed using a three-dimensional treatment planning system and quality assurance procedures that include in vivo dosimetry measurements. The available literature also suggests inhomogeneity correction factors and intensity modulation are superior to conventional open field techniques and should be implemented within developing protocols. Dynamic machine dose modulation is suggested to reduce department impact, removing the need for tissue compensators and accessory shielding devices, while providing significant improvements to treatment time and dose accuracy. Further long-term survival and intensity modulation studies are warranted, including direct comparisons of both dose modulation and treatment efficiency.     

Family Caregivers' Subjective Caregiving Burden,Quality of Life,and Depressive Symptoms Are Associated With Terminally Ill Cancer Patients' Distinct Patterns of Conjoint Symptom Distress and Functional Impairment in Their Last Six Months of Life

Context

Family caregivers constitute a critical component of the end-of-life care system with considerable cost to themselves. However, the joint association of terminally ill cancer patients' symptom distress and functional impairment with caregivers' subjective caregiving burden, quality of life (QOL), and depressive symptoms remains unknown.

Management of pediatric pontine gliomas

We present 36 consecutive patients with intrinsic glioma of the pons. Tumors with exophytic expansion were excluded. There were 16 females and 20 males, ranging in age from 2 to 13 years, median 6 years. The most common presenting symptoms were cranial nerve dysfunction. unsteadiness of gait, and hemiparesis. Computed tomography (CT) showed a hypodense (17/21) or isodense (4/21) expansion of the pons. Five tumors had areas of contrast enhancement. Following information about prognosis and possible types of management, parents decided for or against radiation therapy: twentyfour children underwent irradiation and 12 did not. Median survival among children receiving a full course of irradiation was 280 days, compared to 140 days in an equivalent group of non-irradiated children. Hemiparesis presenting without cranial nerve symptoms and contrast enhancement on CT scan were poor prognostic factors, whereas sex, age, and duration of symptoms at diagnosis were unrelated to prognosis.     

Effects of neurosurgical titanium mesh on radiation dose

The purpose of this study was to determine the dosimetric impact of a neurosurgical titanium mesh in patients treated with 6- and 18-MV photon beams. The effects of a 0.4-mm-thick titanium mesh on the dose profile at 3 regions within a solid water phantom were measured using extended dose range-2 (EDR2) film for 6- and 18-MV photon beams. All measurements were performed with the titanium mesh placed at a depth of 1.5 cm in the phantom. Films were exposed immediately above the mesh, immediately below the mesh, and at a depth of 5 cm from the surface of the phantom. The films were scanned using a scanning densitometer. In the region directly above the titanium mesh, there was an increase in dose of 7.1% for 6-MV photons and 4.9% for 18-MV photons. Directly below the titanium mesh, there was an average decrease in dose of 1.5% for 6-MV photons and an increase of 1.0% for 18-MV photons. At 5-cm depth, for 6- and 18-MV photons, there was a decrease in dose of 2.2% and 0.6%, respectively. We concluded that for cranial irradiation with high-energy photons, the dosimetric impact of a 0.4-mm titanium mesh is small and does not require modification in treatment parameters.     

An analysis of paramagnetic centers in irradiated dentin using electron spin resonance

Summary The ESR spectra produced in irradiated dentin have been studied over a range of incident radiation energies from 50 kVp to 25 MVp. The behavior of the dentin ESR signal strength is similar to that of enamel as a function of the energy of the incident radiation. The magnitude of the dentin ESR signals are, however, up to 10 times smaller than the signals of dental enamel for a given radiation energy. The possible contributions of radiation interaction coefficients, chemical structure, and crystallite size to the differences in ESR spectra are discussed.     

Approaches for end-of-life care in the field of gynecologic oncology: an exploratory study

We sought to explore the Society of Gynecologic Oncologists (SGO) members' opinions and decisions about end-of-life issues and incurable conditions. A survey was mailed to members of the SGO. Their responses were recorded on a Likert scale and entered into a database. The survey explored opinions, experiences, and decisions in managing terminally ill gynecologic oncology patients. Of 900 surveys, 327 were returned (response rate, 36%). Seventy-three percent were men, 89% were white, and 72% were of Christian denomination. Respondents believed that 97% of patients who are dying realize that they are dying but stated only 40% of these patients initiate conversations about end-of-life issues. In contrast, 92% of respondents stated that they initiate end-of-life discussions with patients. Ninety-two percent of respondents thought that the patients should be allowed to make end-of-life choices independently after the facts are given to them. However, 44% thought that it is important to influence the way information is presented, and 54% believe that the gynecologic oncologist (GO) controls the outcome of end-of-life discussions. Although the physicians' sex, race, religion, and age did not correlate with their treatment decisions, religion did correlate with less fear of death (P = 0.011) and less discomfort when talking with patients about death (P = 0.005). Fifty-four percent of respondents believed that the GO controls the outcome of end-of-life discussions, and 40% believe that their actions prolong the process of dying. Expanding our understanding of what motivates GOs to recommend continued treatment over palliation is important for preserving informed patient-motivated end-of-life decisions.     

肺结核线索调查中X线胸透的代价和效益试评

用热释光剂量计测试了受检者胸透体表照射量，结果表明受检者体表照射量符合对数正态分布，几何均值为０．１９ｍＣ·ｋｇ－１，高于一般体检胸透照射量水平。根据危险度系数，估算出由此造成的辐射诱发恶性肿瘤危险度，男女分别为３．５５×１０－６和４．０５×１０－６，后裔遗传疾患的危险度均为４．０×１０－８，由此估计该次实践造成的人均寿命缩短时间为０．５２ｈ·人－１。利用江苏省结核病的患病率、死亡率、化疗治愈率估算出由此次实践带来的人均寿命延长时间为４５．８ｈ·人－１。     

History of Pediatric Oncology

Pediatric oncology emerged as a subspecialty in the United States of America following the observations in 1948 of Farber and his associates of the benefits of chemotherapy for acute leukemia. The establishment of national cooperative chemotherapy groups furthered its development. More recently, the subspecialty has been recognized by the American Board of Pediatrics. Even more recently, training programs for the subspecialty have been given accreditation. Parallel to development of the specialty in the United States has been a similar evolution of pediatric oncology in Europe.     

Rate of PSA rise predicts metastatic versus local recurrence after definitive radiotherapy

: A rising prostate specific antigen (PSA) following treatment for adenocarcinoma of the prostate indicates eventual clinical failure, but the rate of rise can be quite different from patient to patient, as can the pattern of clinical failure. We sought to determine whether the rate of PSA rise could differentiate future local versus metastatistic failure.

: Two thousand six hundred sixty-seven PSA values from 400 patients treated with radiotherapy for localized adenocarcinoma of the prostate were analyzed with respect to PSA patterns and clinical outcome. Patients had received no hormonal therapy or prostate surgey and had ?4 PSA values post-treatment PSA rate of rise, determined by the slope of the natural log, was classified as gradual (< 0.69 log (ng/ml)/year, or doubling time (DT) > 1 year), moderate (0.69-1.4 log (ng/ml)/year, or DT 6 months-1 year), or rapid [>1.4 log (ng/ml)/year, or DT < 6 months].

: SIxty-one percent of patients had non-rising PSA following treatment; 25% of patients with rising PSA developed clinical failure, and 93% of patients with clinical failure had rising PSA. The rate of rise discerned different clinical failure patterns. Local failure occurred in 23% of patients with moderate rate of rise versus 7% with gradual rise (p = 0.0001). Metastatic disease developed in 46% of those with rapid versus 8% with moderate rise (p < 0.0001). By multivariate analysis, in addition to rate of rise, PSA nadir and rate of decline predicted local failure; those with post-treatment nadir of 1–4 ng/ml were five times more likely to experience local failure than nadir < 1 ng/ml (p = 0.0002). Rapid rate of rise was the most significant independent predictor of metastastic failure.

: The rate of PSA rise following definitive radiotherapy can predict clinical failure patterns, with a rapidly rising PSA indicating metastatic recurrence and moderately rising PSA local recurrence. This information could potentially dirent therapy; if the rise predicts metastatic failure hormonal therapy could be cosidereed, while aggressive salvage therapy may benefit subclinical local recurrence identified by a moderate rate of PSA rise.