Head and neck cancer. Reliability of American Joint Committee's staging system as prognostic indicator.

The present American Joint Committee (AJC) staging system for the head and neck cancer does not satisfy the criteria as a prognostic or therapeutic indicator when patients are treated initially with radiation therapy. There are certain groups of patients allocated to advanced AJC stages where the prognosis is more favorable and, thus, should not be grouped with the poor prognosis stages. Recognition of these groups is important for any treatment planning or reporting of the end results.

Stereotaxic radiotherapy technique for small intracranial lesions.

A stereotaxic radiotherapy technique that permits accurate delivery of highly localized dose to a small intracranial target has been developed. The technique facilitates precise integration of the diagnostic and therapeutic procedures including target localization, treatment planning, simulation, repetitive patient irradiation, and daily treatment verification. A conventional linear accelerator and computed tomography scanner as well as special diagnostic and therapeutic guides are used. A suitable dosimetric distribution is achieved using arc therapy with small radiation fields and 10-MV x rays.

Apical lung carcinoma.

During the period 1955 to 1975, 63 consecutive cases of apical lung carcinoma were treated in the Radiation Therapy Division of the University of Michigan Medical Center (UMMC). Supervoltage external radiation alone or combination of radiation and surgery were the main modalities of treatment used in these patients. Our results show 27.9% and 20.9% 3 and 5 years actuarial survival, respectively, in patients who received 5000 to 6000 cGy (rad) of radiation alone. Survival was better in T2 lesions (24.9%) as compared with T3 lesions (7.9%) and in those patients who had no regional adenopathy (30.2% in T2, N0 lesions and 11.6% in T3, N0 lesions). Local osseous and nervous extensions also carried poor prognosis. The results with preoperative irradiation were no better than radiation therapy alone.

High-dose radiation therapy in carcinoma of the pyriform sinus.

In a retrospective analysis of 61 patients with carcinoma of the pyriform sinus, treated primarily with high doses of radiation therapy with surgery reserved for persistent or recurrent tumor, survival rates of 56.5% and 12.4% were found in Stages III and IV, respectively. The two patients with Stage II disease were cured. There were no Stage I patients. The local control of T4 lesions and N2-3 lesions, as well as the survival of patients with Stage IV disease, is poor with radiation alone. This points out the necessity of combining irradiation with surgery and/or chemotherapy for Stage IV disease. The results in early stages with radiation alone are acceptable.

Role of radiation therapy in carcinoma of the hypopharynx.

In a series of 199 patients with hypopharyngeal carcinoma treated with irradiation, the primary tumor was controlled in 63 per cent, 54 per cent, 44 per cent and 14 per cent of T1-T4 lesions, respectively. The five-year actuarial survival for stages I, II, III and IV patients was 60 per cent, 66 per cent, 49 per cent and 18 per cent. It was significantly better in patients with tumors located at the upper hypopharynx (p = 0.024). Early lesions yielded satisfactory results with irradiation alone. Advanced tumors had poor prognosis and other treatment modalities along with irradiation should be tried.

Dosimetry of small radiation fields for 10-MV x rays.

Dosimetry for 10-MV x rays has been extended to radiation fields smaller than 4 X 4 cm which may be suitable for radiation therapy of small lesions, e.g., intracranial tumors, benign or malignant. Special consideration in this study was given to (i) the variation of dose with field size (collimator and phantom scatter), (ii) the central axis percentage depth doses, and (iii) the moving-beam therapy dose distribution. We conclude that simple dosimetric techniques can provide adequate physics background for stereotaxic radiosurgery with small radiation fields and high-energy x rays.

Radiation therapy of carcinoma of the tonsillar region.

From 1960 through 1976, 353 consecutive patients with carcinoma of the tonsillar region were primarily treated with radiation therapy. The mean age of patients was 58 years with males predominating (78%). Patients were classified according to a TNM and stage classification. Most of the tumors were large, and the specific site of origin could not be determined in 33% of the patients. The predominant identifiable sites were the soft palate and uvula, 18%, the anterior tonsillar pillar, 18%, and the tonsillar fossa, 13%. Patients were treated with radiation to doses of 6700 rad given in 48 days and 33 fractions using Cobalt 60 radiation. We found a 91.7% control rate for patients with T1 disease and 76.9%, 49.5%, and 25% for T2, T3, and T4 patients, respectively. The overall local control rate was 62.3%. Surgery was used most often in recurrences for Stage III patients. Salvage surgery was carried out in 93 patients. Surgery was more successful in controlling the disease in patients in whom the primary was controlled by irradiation. Overall, the tumors in 43% of the patients who had surgery were subsequently controlled as a result of this treatment. Metastasis occurred rapidly, with 75 of the patients exhibiting metastases by 18 months. Complications were not related to dose but were slightly higher in patients who had surgery (5%). We conclude that radiation therapy is the preferred treatment for Stage I and II squamous cell carcinoma of the tonsillar region. No satisfactory results were obtained in Stage IV; other approaches should be tried.

Computer controlled hyperthermia unit for cancer therapy.

A versatile hyperthermia control system, based on a microcomputer, provides automated temperature regulation (1 channel) and monitoring (3 channels) and control of microwave output (both on/off and power level), and displays temperature (degree C) and microwave output (watts) graphically in real time; all data are stored on floppy diskette.

Radiation tolerance of the cervical spinal cord.

A total of 109 patients were studied after receiving radiation therapy that included a dose to the spinal cord. In addition to irradiation of the primary site, 59 patients received radiation to the lower neck. Transverse myelopathy developed in three patients; all three had been treated with fields to the lower neck. The dose to the spinal cord at the site of junctional fields was thought to be considerably higher because of the beam divergence from multiple fields employed. The authors stress that prolonged fractionation of treatment, fixation of the head during treatment, precise dosimetry, and close surveillance of the patient are important factors in avoiding radiation myelitis. The authors also stress the importance of controlling divergence of multiple beams by employing appropriate shields.

Irradiation in the treatment of Hodgkin disease: a follow-up report.

From 1971 through 1976, 167 patients with Hodgkin disease received radiation therapy. In 132, staging was determined upon laparotomy; the others had clinical staging. Most patients with stage I or II disease received either mantle or para-aortic-iliac irradiation, while the others received more extensive irradiation with or without chemotherapy. Overall five-year actuarial survival rate was 87%; Stage I, 97%; Stage II, 85%; and Stage III, 82%. Fifty-nine of the 167 patients had relapse of disease, and most relapses were seen in Stage II, located in the nodal sites on the opposite side of the diaphragm. Overall five-year relapse-free survival was 58%; Stage I, 94%; Stage II, 43%; and Stage III, 59%. Survival after the first relapse was 69%. Based on their results, the authors feel that Stage I disease of supradiaphragmatic presentation can be treated effectively with mantle field irradiation alone. In treating Stage II disease, mantle field irradiation alone was not optimal, and the authors recommend subtotal nodal irradiation.

Carcinoma of the oropharynx.

179 consecutive cases of carcinoma of the oropharynx (excluding the tonsillar region) were treated by irradiation from 1960 through 1976. All patients with Stage I tumor survived five years, compared with 56% for Stage II, 62% for Stage III, and 37% for Stage IV. 58% of the primary lesions were controlled by irradiation; the rate ranged from 93.8% for T1 to 37.1% for T4, with a similar decrease by T category regardless of the site of origin. Surgery contributed to salvage of recurrences, but there were slightly more complications after surgery than among patients given irradiation alone (through still fewer than in other studies). It is concluded that high-dose radiotherapy can be curative in early stages while preserving function in the head and neck (particularly the voice). Low-dose irradiation followed by surgery appears to offer no advantage.

Squamous cell carcinoma of the maxillary sinus.

A retrospective analysis of 59 cases of squamous cell carcinoma of the maxillary sinus, which were treated either with radiation alone or combined surgery and radiation, was performed. Fifty-six cases (95%) had T3 and T4 lesions. Our results show that six (66.6%) of nine of T3 and T4 lesions were controlled by combined therapy, while radiation alone controlled 15 (34%) of 44 of T3 and T4 lesions. Five-year actuarial survival of T3 and T4 patients treated with combined therapy was 75% and 33.3%, respectively, while survival of T3 and T4 patients treated with radiation alone was 38.4% and 33.2%, respectively. The five-year actuarial survival for the whole series was 39.3%. It is our opinion that better results could be obtained with surgery followed by radiation therapy in selected cases.

Computer controlled hyperthermia unit for cancer therapy.

Hyperthermia is the artificial elevation of tissue temperature above 41 degrees C with therapeutic intent. Most of the currently used hyperthermia units lack feedback temperature control mechanisms, and, therefore, are not optimal for clinical trials. To solve this problem, we have developed a control system based on a microcomputer. The computer measures the tumor and normal tissue temperature using fine thermocouple sensors and regulates the output of the microwave generator to achieve and maintain the prescribed tumor temperature under specified conditions. Safety procedures are incorporated to avoid heating the tumor or normal tissue beyond predetermined limits.

Evaluation of irradiated mandibles using emission tomography, bone scans, and radiography.

This study compared radiographs, bone scans, and computed emission tomograms with histologic findings in irradiated mandibles of adult Rhesus monkeys. Although osteocytes were lost in the path of the beam, many vessels were partially or totally occluded, the periosteum degenerated, the marrow became fibrotic, and cancellous bone proliferated abundantly, no changes were noted with radiography, conventional bone scanning, or computed emission tomograms. These clinical methods of examination may misrepresent the true condition of irradiated bone because of inadequate sensitivity or balance among factors that control radioactive tracer uptake in bone.

Management of malignant salivary gland tumors.

A total of 54 patients with major salivary gland tumor were treated with radiation therapy at the University of Michigan from 1955 to 1975, inclusive. Fifteen had total resection and radiation, 16 had subtotal resection and radiation, and 23 were inoperable and received radiation only. Local control rate was different between these groups, 86.7%, 75%, 21.7% respectively, as was survival rate at 5 years, 78.4%, 59.8%, 29.9%. In patients with facial nerve palsy, with combined surgery and radiation, 65.3% local control and 49.7% 5-year survival was obtained. Regional neck node metastasis was noted in 25.5% and distant metastasis in 24.1%. Local tumor control was found to be a very important factor in survival: 70.2% survival in patients with local control and 28.7% without. The authors conclude that a combined radical surgery and postoperative radiation would improve the prognosis of these patients with major salivary gland tumors.