Biomedical subjects

P J Cavanaugh

Publications and source records attributed to P J Cavanaugh.

15 recordsLinked to original sources

PubMed1976

Short-course radiation therapy in the treatment of head and neck tumors.

A pilot study undertaken to evaluate short-course, high-increment radiation therapy. This type of treatment was tolerated well by the patients, with a surprisingly low level of acute reaction to the regimen and few late complications. Tumor regression seemed to be earlier than might be expected and involved more than 50% of the tumor in over 75% of the patients following the fourth course of treatment. Preliminary results show that long-range survival rates are at least equivalent to those obtained with the conventional longer treatment regimen. In general, this seems to be a more economical and efficient method of treatment which entails less patient discomfort than the conventional method.

Body Weight↗

PubMed1975

Fractionated dose of 35-MEV fast neutrons and hypoxic tumor cell survival curve.

The determination of the RBE for the MANTA fast neutrons produced by NRL is inprogress, with the model system using tumor cell population kinetic response patterns assayed in vitro after irradiation in vivo. Ascites tumor cells BW-5147 were irradiated with a clinically usable fast neutron beam from the NRL cyclotron, which is produced by accelrating deuterons to 35 MeV and using htem to bombard a thick berylliumtarget. The comparison of dose-effect relationships was made for doses ranging from30 to 1000 rads. The doses required for an isoeffect on BW-5147 hypoxic tumor cell survival and impairment of its reproductive capacity from fast neutron exposure were not different wheither it was given a single dose or the same dose given in three fractions separated by long recovery periods in situ. No intracellular repair of sublethal injury when the dose was given in three fractions, although the hypoxic BWp5147 tumor cells haveno effective reoxygenation or repopulation in this time interval. The RBE for the fast neutron beam is 4 relative to x rays for fractionated doses at the surviving fractionlevel of 0.6-0.7, while the RBE IS 2.5 FOR SINGLE DOSES. However, at a surviving fraction of 0.1, the RBE is 1.9 for single and 2.8 for fractionated doses. Analysis of thedaily cell population rate or mitotic delay between the two types of radiations at a similiar level of survival.

Animals↗

PubMed1975

Considerations appropriate to a clinical trial of definitive radiation therapy in adenocarcinoma of the pancreas.

The Author describes criteria for selection of patients who might be eligible for entry into a clinical trial of definitive Radiation Therapy for adenocarcinoma of the pancreas. Most emphasis is placed on careful surgical staging, target volume and location, and the use of bypass procedures when appropriate.

Adenocarcinoma↗

PubMed1975

Clinical trial of atmospheric oxygen breathing during radiotherapy for cancer of the oropharynx.

A randomized clinical trial of atmospheric oxygen breathing during radiotherapy of advanced cancer of the tonsillar region has been conducted. In order to achieve a high level of inspired oxygen, a closed system with a "head tent" was used. Over 2 years after treatment, 30 percent of the oxygen patients survived without evidence of disease compared to 17 percent in the control group.

Carcinoma, Squamous Cell↗

PubMed1974