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Radiotherapy of Ewing's sarcoma. Local control with and without intensive chemotherapy.

Primary tumor control rates were studied in two groups of patients with Ewing's tumor. They received high doses of radiation combined with a standard chemotherapy regimen incorporating multiple agents. Another 17 had either less chemotherapy or none at all. The data suggest that treatment dose and control are correlated and that intensive chemotherapy contributes to destruction of the primary tumor.

Adolescent

Proposal for a program in particle-beam radiation therapy in the the United States. A report from the Committee for Radiation Oncology Studies (CROS) and its Particle Subcommittee.

The Program for Particle Therapy proposes utilization of hospital-based particle generators in a nationwide program to evaluate, through meaningful clinical trials, particle radiation therapy and the impact its utilization can have in cancer care. The scientific rationale for use of particle therapy compared to conventional radiation in the effort to achieve uncomplicated local control of cancer, to heal, cure and palliate the patient, indicates the advantages of particle therapy consist of either or both a) enhanced biological effect and b) physical properties leading to improvement in dose distribution. It has been estimated that in tho control local-regional cancer. Any new modality enabling the therapist to increase dose to tumor, while sparing critical normal tissue, can enhance local control and benefit systemic therapy. Limited clinical trials to date warrant further definitive clinical study of particle beams. Physical and biologic considerations of fast-neutron beams have been essentially completed; equipment design, availability, and predicted reliability are good; and the medical community has indicated support of further study. A major clinical investigation can be implemented to provide the scientific basis for judging clinical merit of use of high LET radiations. Concurrently, the first phase of work can be started with protons, negative pions, and heavy ions. It is anticipated that clinical results will accrue much more rapidly with hospital-based units for clinical trials; this Program proposes this transfer of particle technology from the laboratory to such hospital-based facilities in two phases, over a 10-year period.

Clinical Trials as Topic

Surgical treatment of squamous cell carcinoma of the oral tongue: factors influencing survival.

One hundred fifty patients with squamous cell carcinoma of the oral tongue (anterior two thirds) treated initially by surgery alone were analyzed and factors influencing survival were evaluated. Thirteen patients who died without evidence of disease in less than five years were excluded, leaving 137 determinate cases for review. The overall survival was 67.9%. The presence or absence of cervical node metastases appeared to be the most important determining factor in this series. The size of the primary lesion in itself did not play a substantial role in local control. However, overall survival was affected because the larger the primary lesion the higher the incidence of cervical metastases, and therefore, the lower the survival. It is concluded that partial glossectomy is effective treatment for control of localized disease (92.7%). Since cervical node metastases lowered the survival figures to 31%, it appears that more aggressive prophylactic treatment in the form of neck dissection or radiotherapy is indicated for lesions larger than 2 cm.

Carcinoma, Squamous Cell

The role of irradiation in the management of head and neck cancer: analysis of results and causes of failure.

The records of patients with squamous cell carcinoma of the oral cavity, oropharynx, supraglottic and glottic larynx, whose primary lesion was treated with radiation therapy from 1964 through 1973, were reviewed. End points of the study are local control rate at the primary site, ultimate control with surgical salvage, and causes of failure. The local control rate at the primary site was 90% for T1 lesions, 80% for T2 lesions, and approximately 70% for selected T3 lesions. The control rates for the advanced T3 and T4 lesions are unsatisfactory; therefore, preoperative or postoperative irradiation is combined with appropriate surgical procedures to improve the local control rates and in some instances survival rates. Analysis of cervical node metastases treatment shows that the incidence of local recurrence in the radically dissected neck can be significantly reduced with either pre- or postoperative irradiation. Elective irradiation of initially clinically uninvolved areas of the neck (both ipsilateral and contralateral) has almost eliminated subsequent nodal metastases.

Carcinoma, Squamous Cell

Outcomes of stereotactic radiosurgery for spine multiple myeloma-a systematic review.

Spinal involvement in multiple myeloma (MM) commonly results in pain, vertebral instability, epidural spinal cord compression, and neurological deficits. Although conventional external beam radiation therapy (EBRT) remains the standard radiation modality because of the radiosensitive nature of MM, stereotactic radiosurgery (SRS) has emerged as a highly conformal treatment option capable of delivering focal high-dose radiation while sparing adjacent spinal cord structures and uninvolved bone marrow. This systematic review evaluated the clinical outcomes and safety profile of SRS for spinal MM. A systematic review of the literature was performed to identify studies evaluating SRS for spinal MM. Extracted variables included patient demographics, tumor characteristics, treatment parameters, radiographic outcomes, pain response, neurological outcomes, local control, overall survival, and adverse events. Three retrospective studies comprising 133 patients and 181 treated spinal lesions met the inclusion criteria. Median patient age ranged from 59 to 65 years, with a slight male predominance across studies. Thoracic spine lesions represented the most treated region (55.5-67.7%). Median prescribed SRS dose was 14-16 Gy, predominantly delivered in a single fraction. Median follow-up ranged from 11.2 to 27.8 months. Local control rates ranged from 89.4 to 100%, with 6- and 12-month local control rates of 94% and 91%, respectively, in one study. Pain improvement was reported in 41-88% of treated patients/sites, with a median time to pain relief of 1.6 months in one cohort. Neurological improvement occurred in 56-71.4% of patients with preexisting deficits. Reported adverse events included vertebral compression fractures, fracture progression, pain flare, and tracheoesophageal fistula. De novo vertebral fractures ranged from 3.6 to 7%, while fracture progression ranged from 14 to 18%. SRS appears to provide excellent local control and meaningful pain and neurological improvement in patients with spinal MM, with acceptable toxicity profiles. The highly conformal nature of SRS may preserve uninvolved bone marrow and facilitate continuation of systemic therapy. However, the current evidence is limited to small retrospective studies with heterogeneous reporting, and further prospective comparative studies are needed to better define the role of SRS relative to conventional EBRT in spinal MM.

Humans

Enhancement of local tumour control by misonidazole and hyperthermia.

Combination treatment of a C3H mammary carcinoma with misonidazole, hyperthermia and radiation resulted in greater local tumour control than with any of these agents singly or in pairs. Dose modification factors for the 3-fold combinations were 3.28 when tumours were immersed in a 42.5 degree C waterbath for 1h after irradiation, and 5.03 at 43.0 degrees C. Cytotoxicity of misonidazole alone was slight, as reflected histologically and in tumour growth. Hyperthermia had a marked effect on these two parameters. Foot damage by hyperthermia was greatest when feet were taped.

Animals

Application of the mathematics of coupled oscillator systems to the analysis of the neural control of locomotion.

In many animals, the activities of limb motor neurons are rhythmic during locomotion. In some animals it is known that each limb is innervated by a local control center that resides in a discrete portion of the central nervous system. Each local control center is a biological oscillator. Since each limb moves with the same frequency as each other limb and with regulated phase delay with respect to each other limb, then it follows that the local control centers are coupled to one another. The locomotory pattern generator within the central nervous system is therefore a coupled oscillator system. The mathematics of coupled oscillator systems can assist in the construction of a model of the neural pattern generator. This model can be utilized to formulate testable predictions concerning the neural control of locomotion. Experimental data gathered from organisms in several phylums are consistent with the predictions of the model.

Action Potentials

Evaluation of fast neutron teletherapy for advanced carcinomas of the major salivary glands.

This review analyzes the local control rate of fast neutron beam teletherapy for malignant salivary gland carcinomas compared to conventional photon irradiation at the same institution. Thirty patients with malignant parotid or submaxillary gland tumors were treated with either cobalt-60 (19 patients) or neutrons +/- photons (11 patients). The 19 photon-treated patients were historical controls. No advantage is found for neutrons in patients with tumors less than 3 cm where 100% local control was achieved with either modality. In patients with tumor masses 3-6 cm in size, neutrons demonstrated a possible advantage with a local control rate of 100% (followup, 7-18 months) compared to a control rate of 33% with conventional photon irradiation. Acute treatment-related morbidity was slightly greater in neutron-treated patients, but no long-term complications have been observed to date.

Evaluation Studies as Topic

Carcinoma of the oral tongue and floor of mouth: fifteen years' experience with linear acceleration therapy.

One hundred fourteen patients with carcinoma of the oral tongue and floor of mouth were treated with high-dose megavoltage radiation at Stanford University from 1956 to1970. Actuarial 5-year survival for 56 patients with oral tongue lesions was: T', 73; T', 37%; and T', 19%. Similarly, for 58 patients with lesions of the floor mouth, 5-year survival was: T', 73%; T', 37%; and T', 25%. Local control of the primary was obtained in oral tongue T' lesions 10 of 11 times; T', 5 of 8; and T', 13 of 36 times. For floor of mouth, local control was: T', 22 of 26;T', 7 of 14; andT', 3 of 15. There was an indication that better control was obtained if interstitialtherapy was a planned part of the treatment. Dose for local control when external radiation alone was utilized was usually over 1900 rets. Patients with initially clinicallynegative nodes (TXNO) who had a low radiation dose to primary echelon lymph nodes developed later cervical lymph node metastases 38% of the time. In no case did late metastatic disease appear in patients whose necks were treated prophylactically.

Aged

Combined therapeutic approach to malignant lacrimal gland tumors.

The medical records of 13 patients with primary malignant lesions of the lacrimal gland revealed adenoid cystic carcinoma as the most common malignant tumor. The histologic cell type, neural invasion, and bony destruction were correlated with localized control and ultimate survival. Surgical removal of the lacrimal gland was adequate treatment for low-grade mucoepidermoid carcinoma confined to the gland itself. Combining a radical surgical removal of the area in planned sequence with high voltage radiation therapy offered the only reasonable hope for localized control in the more aggressive cell types or in tumors with neural invasion or bony involvement. A 40%-localized control and survival rate was achieved in the adenoid cystic carcinoma group of patients. Radiation therapy administered for cancer that obviously recurs after surgical resection was generally unsuccessful.

Adenocarcinoma

Randomized study of control of the primary tumor and survival using preoperative radiation, radiation alone, or surgery alone in head and neck carcinomas.

Fifty-five selected patients with previously untreated squamous cell carcinoma of the head and neck regions were studied in a randomized, prospective manner. The three treatment categories were primary radiation (Gp R), primary surgery (Gp S), and preoperative radiation of 4000 rads in four weeks (Gp R/S). The local control rates for the 44 evaluable patients with a two-year minimum followup were 24%, 39%, and 43% respectively. Further treatment attempts in patients failing initial therapy yielded local control rates of 35%, 39%, and 43% for Gp R, Gp S, and Gp R/S, respectively. None of the local control rates nor the corresponding survival curves were significantly different at P less than 0.10. However, the group sizes were sufficiently small that true differences might not have been detected. Postoperative complications were higher in the primary radiation failures subsequently operated upon compared to the primary surgery group (P = 0.07).

Carcinoma, Squamous Cell