Subject(s)
Personality Disorders/psychology , Phobic Disorders/psychology , Adult , Female , Humans , Male , Middle Aged , Psychopathology , Social EnvironmentABSTRACT
From 1955 to 1976, 111 patients were treated with definitive radiotherapy for epidermoid carcinoma of the nasopharynx. There was a definite correlation between recurrence at the primary site and T-stage; 9.5% of T1-2 patients, 38.1% of T3 patients and 54.1% of T4 patients had local recurrences. Similarly, failure in the neck correlated with N-stage, being negligible for N0 and N1 but 28.6% for N2 and 36.1% for N3. The incidence of distant metastases had no correlation with T-stage but correlated very closely with N-stage. The patients were grouped into four T and N categories, T1-2 N0-1, T1-2 N2-3, T3-4 N0-1, and T3-4 2-3. The five year relapse-free survival for the T1-2 N0-1 category was 69% but was only about 20% for each of the other three categories. The major cause of poor survival for the T3-4 N0-1 category was recurrence at the primary site, whereas for the T1-2 N2-3 and T3-4 N2-3 categories, it was the high incidence of distant metastases, approximately 50%. Recommendations are to increase dose at the primary site for T3-4 N0-1 patients and to institute clinical trials testing adjuvant chemotherapy for patients with neck stages N2 and N3.
Subject(s)
Carcinoma, Squamous Cell/radiotherapy , Nasopharyngeal Neoplasms/radiotherapy , Actuarial Analysis , Carcinoma, Squamous Cell/pathology , Dose-Response Relationship, Radiation , Humans , Lymphatic Metastasis , Nasopharyngeal Neoplasms/pathology , Neoplasm Metastasis , Neoplasm Recurrence, Local , Neoplasm Staging , Radiotherapy/adverse effects , Radiotherapy/methods , Retrospective StudiesABSTRACT
The design and construction of a thin-walled parallel plate ionization chamber is described. The chamber makes use of a sputtered collecting electrode. The characteristics of this chamber include low leakage (less than 10(-13) A), no stem effect, and reproducibility within 1%. No polarization effects have been seen for electron beams over an energy range 7-25 MeV while for cobalt 60-25 MV photon beams, it is only 10%-15%.
Subject(s)
Radiometry/instrumentation , Radiotherapy Dosage , Radiotherapy, High-EnergyABSTRACT
A Lucite sandwich mold containing Iridium-192 wire for use in the treatment of soft palate carcinoma is described. This mold is very simple to use, produces a homogeneous (+/- 10%) radiation field across the midplane of the tumor, and requires minimal machinist time.