Surgery and proton radiation therapy for pediatric base of skull chordomas: Long-term clinical outcomes for 204 patients.

Background: Data on clinical outcomes for base of skull (BOS) chordomas in the pediatric population is limited. We report patient outcomes after surgery and proton radiotherapy (PRT).

Methods: Pediatric patients with BOS chordomas were treated with PRT or combined proton/photon approach (proton-based; for most, 80% proton/20% photon) at the Massachusetts General Hospital from 1981 to 2021.

Early breast development in overweight girls: does estrogen made by adipose tissue play a role?

Background: Girls who are overweight/obese (OB) develop breast tissue but do not undergo menarche (the first menstrual period) significantly earlier than girls of normal weight (NW). It has been proposed that estrogen synthesized by adipose tissue may be contributory, yet OB do not have higher serum estrogen levels than NW matched on breast stage. We hypothesized that estrogen synthesized locally, in mammary fat, may contribute to breast development.

Impact of aeration change and beam arrangement on the robustness of proton plans.

This study determines the impact of change in aeration in sinonasal cavities on the robustness of passive-scattering proton therapy plans in patients with sinonasal and nasopharyngeal malignancies. Fourteen patients, each with one planning CT and one CT acquired during radiotherapy were studied. Repeat and planning CTs were rigidly aligned and contours were transferred using deformable registration.

American Association of Physicists in Medicine Task Group 263: Standardizing Nomenclatures in Radiation Oncology.

A substantial barrier to the single- and multi-institutional aggregation of data to supporting clinical trials, practice quality improvement efforts, and development of big data analytics resource systems is the lack of standardized nomenclatures for expressing dosimetric data. To address this issue, the American Association of Physicists in Medicine (AAPM) Task Group 263 was charged with providing nomenclature guidelines and values in radiation oncology for use in clinical trials, data-pooling initiatives, population-based studies, and routine clinical care by standardizing: (1) structure names across image processing and treatment planning system platforms; (2) nomenclature for dosimetric data (eg, dose-volume histogram [DVH]-based metrics); (3) templates for clinical trial groups and users of an initial subset of software platforms to facilitate adoption of the standards; (4) formalism for nomenclature schema, which can accommodate the addition of other structures defined in the future. A multisociety, multidisciplinary, multinational group of 57 members representing stake holders ranging from large academic centers to community clinics and vendors was assembled, including physicists, physicians, dosimetrists, and vendors.

Effect of body mass index and albumin on mortality rates for adult African-American hemodialysis patients.

Purpose: The purpose of this retrospective descriptive study was to investigate if body mass index (BMI) and serum albumin (SA) impacted mortality rates in adult African-American patients on hemodialysis (HD).

Data Sources: Records of 204 patients on HD (N = 204) from a clinic in the metropolitan Detroit area were examined for the period January 1, 2007-December 31, 2012 to determine the relationship of BMI and SA on mortality rates in this population. Logistics regression was utilized to analyze the association of several risk factors (BMI and SA) on survival (mortality rates).

Vitamin E tocotrienol supplementation improves lipid profiles in chronic hemodialysis patients.

Purpose: Chronic hemodialysis patients experience accelerated atherosclerosis contributed to by dyslipidemia, inflammation, and an impaired antioxidant system. Vitamin E tocotrienols possess anti-inflammatory and antioxidant properties. However, the impact of dietary intervention with Vitamin E tocotrienols is unknown in this population.

Effects of protein and omega-3 supplementation, provided during regular dialysis sessions, on nutritional and inflammatory indices in hemodialysis patients.

Purpose: Malnutrition and chronic inflammation in dialysis patients negatively impacts prognosis. However, intervening to correct this problem (through nutritional supplementation) is often hampered by poor compliance due to both medical and socioeconomic barriers. We have therefore performed a pilot study to investigate the technical feasibility of "directly observed treatment" of nutritional supplementation (protein and omega-3 fatty acids), administered during regular dialysis sessions.

A case study in proton pencil-beam scanning delivery.

Purpose: We completed an implementation of pencil-beam scanning (PBS), a technology whereby a focused beam of protons, of variable intensity and energy, is scanned over a plane perpendicular to the beam axis and in depth. The aim of radiotherapy is to improve the target to healthy tissue dose differential. We illustrate how PBS achieves this aim in a patient with a bulky tumor.

Proton beam radiation therapy for skull base adenoid cystic carcinoma.

Objective: To determine the treatment outcome and prognostic factors in patients with adenoid cystic carcinoma of the skull base treated with proton beam radiation therapy.

Design: Retrospective analysis.

Setting: Massachusetts General Hospital, Massachusetts Eye and Ear Infirmary, and Harvard Medical School, Boston.

Proton beam irradiation for neovascular age-related macular degeneration.

Objective: To evaluate safety and visual outcomes after proton therapy for subfoveal neovascular age-related macular degeneration (AMD).

Design: Randomized dose-ranging clinical trial.

Participants: One hundred sixty-six patients with angiographic evidence of classic choroidal neovascularization resulting from AMD and best-corrected visual acuity of 20/320 or better.

Combined proton and photon irradiation for craniopharyngioma: long-term results of the early cohort of patients treated at Harvard Cyclotron Laboratory and Massachusetts General Hospital.

Purpose: We report the results of the early cohort of patients treated for craniopharyngioma with combined proton-photon irradiation at the Massachusetts General Hospital and the Harvard Cyclotron Laboratory.

Methods And Materials: Between 1981 and 1988, 15 patients with craniopharyngioma were treated in part or entirely with fractionated 160 MeV proton beam therapy. The group consisted of 5 children (median age, 15.

Conservation treatment of the eye: Conformal proton reirradiation for recurrent uveal melanoma.

Purpose: To evaluate the outcomes of a second course of proton beam radiation therapy (PBRT) in patients with recurrent uveal melanoma.

Methods And Materials: Thirty-one patients received a second course of PBRT. The mean interval between the first and the second PBRT course was 50.

The maximin principle of pi-radical packings.

A two-term model is proposed for hydrocarbon and N-containing pi-radicals which are in close contact with one another. The first term is attractive (due to partially occupied frontier pi-orbitals), and the second, repulsive (due to hard-core repulsion between close-lying atoms). This model is applied to dimers where intermolecular contacts are closer than <0.

Proton radiation therapy for retinoblastoma: comparison of various intraocular tumor locations and beam arrangements.

Purpose: To study the optimization of proton beam arrangements for various intraocular tumor locations; and to correlate isodose distributions with various target and nontarget structures.

Methods And Materials: We considered posterior-central, nasal, and temporal tumor locations, with straight, intrarotated, or extrarotated eye positions. Doses of 46 cobalt grey equivalent (CGE) to gross tumor volume (GTV) and 40 CGE to clinical target volume (CTV) (2 CGE per fraction) were assumed.

Intensity modulation in radiotherapy: photons versus protons in the paranasal sinus.

Purpose: The purpose of this study is to investigate whether successive tightening of normal tissue constraints on an intensity modulated X-ray therapy plan might be able to improve it to the point of clinical comparability with the corresponding intensity modulated proton therapy plan.

Materials And Methods: Photon and proton intensity modulated plans were calculated for a paranasal sinus case using nominal dose constraints. Additional photon plans were then calculated in an effort to match the dose-volume histograms of the critical structures to those of the proton plan.

Neuroendocrine tumors of the sinonasal tract. Results of a prospective study incorporating chemotherapy, surgery, and combined proton-photon radiotherapy.

Background: The authors report the results of a prospective study of patients with malignant neuroendocrine tumors of the sinonasal tract who received multimodality treatment incorporating high-dose proton-photon radiotherapy.

Methods: Nineteen patients with olfactory neuroblastoma (ONB) or neuroendocrine carcinoma (NEC) were treated between 1992 and 1998 on a prospective study. Four patients had Kadish Stage B disease, and 15 patients had Kadish Stage C disease.

3-D-conformal radiation therapy for pediatric giant cell tumors of the skull base.

Background: Giant cell tumors (GCT) of the base of skull are rare neoplasms. This report reviews the treatment of four pediatric patients presenting with aggressive giant cell tumor, using fractionated and combined, conformal proton and photon radiation therapy at Massachusetts General Hospital and Harvard Cyclotron Laboratory.

Patients And Methods: Three female patients and one adolescent male, ages 10-15 years, had undergone prior, extensive surgical resection(s) and were treated for either primary (two patients) or recurrent (two patients) disease.