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H Castro-Vita

Publications and source records attributed to H Castro-Vita.

4 recordsLinked to original sources
PubMed1995

Carcinoma of the uterine cervix. I. Impact of prolongation of overall treatment time and timing of brachytherapy on outcome of radiation therapy.

PURPOSE: Some studies have described decreased pelvic tumor control and survival rates in invasive carcinoma of uterine cervix when the overall time in a course of definitive irradiation is prolonged. We attempt to confirm or deny these observations and evaluate the impact of timing of brachytherapy on outcome. We also explore the hypothesis that more extensive tumors technically require prolongation of the course of irradiation; thus, decreased tumor control and survival in these patients may not necessarily be the result of time/dose factor. METHODS AND MATERIALS: Records of 1,224 patients (Stage IB to III) treated with definitive irradiation (combination of external beam and two intracavitary insertions to deliver doses of 70 to 90 Gy to point A) were reviewed. Follow-up was obtained in 97% of the patients (median, 12 years; minimum, 3 years; maximum, 28 years). The relationship between outcome and overall treatment time and time of intracavitary insertions was analyzed in each stage and according to tumor size/extent. RESULTS: There was strong correlation between overall treatment time (OTT) and tumor stage (< or = 7 weeks: 81% for Stage IB; 74% for Stage IIA; 52% for Stage IIB; and 47% for Stage III). Interruptions of therapy accounting for prolongation of treatment time occurred in 25-30% of patients, most frequently because of holidays and weekends and side effects of therapy. Overall treatment time had a major impact on pelvic tumor control in Stages IB, IIA, and IIB; in Stage IB 10-year actuarial pelvic failure rates were 7% with OTT < or = 7 weeks, 22% with 7.1 to 9 weeks, and 36% with > 9 weeks (p < or = 0.01). For Stage IIA the corresponding values were 14%, 27%, and 36% (p = 0.08), and in Stage IIB pelvic failure rates were 20%, 28%, and 34%, respectively (p = 0.09). In Stage III, pelvic failure was 30%, 40%, and 50%, respectively (p = 0.08). There was also a strong correlation between OTT and 10-year cause-specific survival (CSS); in Stage IB rates were 86% with OTT of < or = 7 weeks, 78% for 7.1 to 9 weeks, and 55% for > or = 9 weeks (p < 0.01). The corresponding rates in Stage IIA were 73%, 41%, and 48% (p < or = 0.01). For patients with Stage IIB, CSS rates were 72% for OTT < or = 7 weeks, 60% for 7.1 to 9 weeks, and 70% for > 9 weeks (p = 0.01). Patients with Stage III disease had 45% 10-year CSS when treatment was delivered in 9 weeks or less and 36% for longer overall times (p = 0.16). In multivariate analysis of patients with Stage IB and IIA, OTT and clinical stage were the most important prognostic factors for pelvic tumor control, disease-free survival, and CSS. Tumor size was a prognostic factor for CSS. In Stages IIB and III, OTT, clinical stage, unilateral or bilateral parametrial invasion, and dose to point A were significant prognostic factors for pelvic tumor control, disease-free survival, and CSS. Prolongation of time had a significant impact on pelvic tumor control and CSS regardless of tumor size, except in Stage IB tumors < or = 3 cm. Regression analysis confirms previous reports that prolongation of OTT results in decreased pelvic tumor control rate of 0.85% per day for all patients, 0.37% per day in Stages IB and IIA, 0.68% per day in Stage IIB, and 0.54% for Stage III patients treated with > or = 85 Gy to point A. Performance of all intracavitary insertions within 4.5 weeks from initiation of irradiation yielded decreased pelvic failure rates in some groups of patients (8.8 vs. 18% in Stage IB and IIA tumors < or = 4 cm and 12.3 vs. 35% in Stage IIB) (p < or = 0.01). CONCLUSIONS: Prolongation of treatment time in patients with Stage IB, IIA, IIB, and III carcinoma of the uterine cervix has a significant impact on pelvic tumor control and CSS. The effect of OTT was present regardless of tumor size except in Stage IB tumors < or = 3 cm.

Actuarial Analysis↗
PubMed1983

Improved survival in cases of intracranial ependymoma after radiation therapy. Late report and recommendations.

A publication from the University of Rochester Cancer Center in 1975 suggested an improvement in the survival time of patients with intracranial ependymomas in whom an aggressive postoperative radiation therapy approach had been adopted. The regimen was tailored to the aggressiveness and spread patterns of these tumors and therefore considered the patient's age, tumor histopathology and location, and status of the subarachnoid space and cerebrospinal fluid (CSF). The authors proposed using whole brain (WB) fields for all patients with low-grade supratentorial tumors, and WB with cervical cord field extensions for low-grade infratentorial tumors if either group had no CSF or subarachnoid evidence of spinal metastases. They also proposed using craniospinal irradiation for all patients with high-grade ependymomas (regardless of location) or with low-grade infratentorial tumors with positive CSF or subarachnoid findings of spinal metastases. Recommended doses were as follows: 4500 rads to the whole brain, 5500 rads to the primary tumor volume, and 3000 to 4000 rads to the spine, depending on its subarachnoid status. Children aged 3 years or under were to receive 80% of these doses and more protracted daily treatments. Analysis of the updated experience indicates that in 51 patients treated with this approach these criteria have yielded a beneficial and consistent increase in the survival time. A 69% 10-year survival rate has been observed (75% for low-grade and 67% for high-grade ependymomas). A multifactorial analysis of survival by prognostic factors and by grouping of prognostic factors, analysis of failures, autopsy findings, and quality of survival is presented and discussed.

Adolescent↗
PubMed1980

Medulloblastomas.

"Analysis of 29 cases evaluated at SMG, Rochester, N.Y." This study analyzed 29 patients with the diagnosis of medulloblastoma evaluated at Strong Memorial Hospital, Rochester, New York. Twenty-three patients received combined (surgery and radiotherapy) treatment. Six had surgery alone. Chemotherapy was never employed as a primary treatment, however, two cases were treated with drugs at the time of relapse. The patients having craniospinal irradiation had a better survival rate when compared with the group receiving cranial irradiation or surgery alone. The five year survival rate for the first group was 50% versus 20% for the second group and 0% for the third group. The main cause of failure was recurrence in the posterior fossa. Fifteen patients failed in this area representing 88% of the total failures. Seeding to the spinal cord was determined in 5 patients, four of whom did not have spinal cord irradiation. One patient failed outside the field of treatment in the conus medullaris six months after radiation.

Adolescent↗