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Three dimensional visualization of tumor and normal tissues are often valuable in precision treatment planning for radiation therapy of cancer. This is often not possible in many remote treatment facilities because of the high cost of imaging and computer equipment. At the University of Southern California, School of Medicine we are developing and testing a high speed, wide area, computer communications network to provide access to such resources from remote locations. In this paper, we present our concept of a Virtual Academic Medical Center, our network design and report on initial evaluations of effectiveness and clinical acceptability of 3D, CT simulation and treatment planning from a distance.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Publisher Summary The hormones play an essential role, in all species, in the development and function of ovaries and testes, but in most species with Y-determined sexual differentiation, administration of androgens or estrogens does not cause sex reversal. This chapter explains the mechanism by which genetic sex is ultimately translated into phenotypic sex because the mechanisms are different in the two types of mammals. In the marsupial, chromosomal directly dictates major aspects of the sexual phenotype. There is some evidence that genetic factors may control directly at least one sexually dimorphic trait in the eutherian mammal: one or more Y-linked traits appear to influence height and tooth size independent of endocrine function. The human Y chromosome has been mapped by YAC cloning, but the specific gene(s) responsible for these growth phenomena has not been identified. The mechanisms by which the sexual phenotypes form in man and marsupial may not be totally dissimilar. In both, major components are controlled by testicular hormones and there is a direct genetic component, the difference being that the direct genetic sex contribution to the male phenotype is less important in the eutherian mammal.

The early promise that nuclear medicine offered to the cancer patient has been fully kept with respect to diagnosis. In the area of therapy, the results have been far less clear-cut. But a number of new and highly imaginative approaches—often involving interactions with other therapeutic modalities—may justify renewed although still cautious optimism about the future of cancer treatment.

The radiation therapy oncology group (RTOG) has conducted two studies testing the value of extended-versus limited-fields in carcinoma of the prostate. RTOG protocol 75-06 tests the value of paraaortic irradiation in patients with locally advanced tumors limited to the pelvis. RTOG protocol 77-06 tests the value of pelvic irradiation in patients with tumors limited to the prostate. Two hundred sixty-eight evaluable patients have been entered on RTOG 75-06, and 219 on RTOG 77-06 prior to 1981. This is a preliminary report on treatment-related morbidity in patients followed for a minimum of 1 year. Treatment-related morbidity has been classified according to a five-grade severity classification schema and correlated with the protocol option assignment in order to determine whether the use of extended fields had an effect on the incidence of side effects. Thirty-one percent of 268 patients on RTOG 75-06 and 34% of 219 patients on RTOG 77-06 had some form of treatment side effects. The majority (over 80%) of these were mild (grade 1 and 2) and by definition did not interfere with the patients' performance (life style). Only three patients on RTOG 75-06 and one on RTOG 77-06 had grade 4 complications (by definition requiring a surgical intervention). No fatal (grade 5) complications have been recorded so far. The use of paraaortic fields in RTOG 75-06 and pelvic fields in RTOG 77-06 have not resulted in a significant increase of GI or GU morbidity at this time. The only statistically significant trend was the incidence of postirradiation genital and lower extremity edema which strongly correlated with the extent of staging lymphadenectomy.

• Seventy-nine patients with head and neck malignancies were treated using afterloading interstitial iridium 192 techniques at Los Angeles County-University of Southern California Medical Center and Southern California Cancer Center from Feb 1, 1974, to Nov 30, 1975. Twelve of the 13 T 1 and T 2 lesions and 17 of 25 T 3 and T 4 lesions remain locally controlled to a minimum follow-up period of 24 months. Surgical salvage in case of treatment failure is possible with low morbidity because of relatively low external irradiation to the total volume. Twenty of 41 patients who were reirradiated for persistent or recurrent cancers still have local control to a minimum follow-up period of 24 months. We discuss sites of involvement, implantation techniques, reactions, and complications. ( Arch Otolaryngol 106:541-546, 1980)

The authors treated 83 patients with carcinoma of the breast using a combination of external and interstitial irradiation at Los Angeles County--University of Southern California Medical Center and Southern California Cancer Center between February 1, 1974, and May 31, 1977. All 30 patients who had T1 and T2 lesions, and who were followed for a minimum period of 24 months (24-50 months) are clinically still free of disease. Thirty-nine of 53 patients with T3 and T4 lesions, who were followed for a minimum of 30 months (30-56 months) are still alive with local control. Details of treatment techniques, dosimetry, results and complications are presented.

After-loading implantation techniques apparently offer an effective alternative in the management of persistent (or recurrent) oropharynx and oral cavity carcinoma postirradiation. A total of 29 patients with such lesions was treated from February 1974, to July 1975, in the LAC/USC Radiation Medicine Section, using after-loading 192Ir implantation techniques. These patients all had extensive persistent cancer after "full tolerance" irradiation (with or without previous surgery) and were referred for palliation or for possible salvage. Additional doses administered ranged from 5000 to 7000 rads in three to five days. Eighteen of the 29 patients (63%) have had complete local control for 18 to 36 months. These patients have maintained a relatively satisfactory palliative status. Ten of the 29 are dead. Follow-up periods are short, but early indications are that problem patients with persistent cancer after "full tolerance irradiation" can be salvaged, or at least satisfactorily palliated, with after-loading interstitial implant techniques. Clinical details, sites of involvement, implantation techniques, dosimetry methodology, reactions and complications will be described.

Retreatment of persistent (or “recurrent”) carcinoma of the head and neck by means of after-loading 192Ir techniques may prove quite satisfactory. A total of 64 patients were retreated by these techniques from February, 1974 to October, 1975 at the Los Angeles County—University of Southern California Medical Center and the Southern California Cancer Center. Follow-up periods, averaging only 24 months (18 to 36 months), are too short for statistically significant evaluation of survival, but the “response rate” has been gratifying. Only 11 of our 64 patients (17%) have shown no satisfactory response to re-irradiation by interstitial implant. Thirty-one of the 64 patients (49%) have had local control with “good palliation”. Twenty-two of the 64 (34%) had at least 50% regression of tumour with “fair” palliation. Thus 83% have had satisfactory response to retreatment. A considerable number of these have survived to the date of this report. Whereas 36 of the 64 (56%) are now dead, 28 of the 64 otherwis...

During 1920 to 1954 there were 1,165 patients judged to have had recurrent cancers within a 10 year period following radiologic treatment of 4,308 cases of squamous cell carcinoma of the uterine cervix.Forty-seven per cent of recurrences was detected by ¾ year, 60 per cent by 1 year, 73 per cent by 2, and 100 per cent by 9 years of follow-up for recurrences after radiotherapy. Thirty-seven per cent were pure cervical recurrences, 10.3 per cent pure vaginal, 2.4 per cent pure cervical and vaginal, 24.7 per cent parametrial with or without central disease, 10.8 per cent distant with or without pelvic disease. In 14.3 per cent of cases the exact sites of recurrences were not determined.Retreatment was administered by individualized methods of roentgen irradiation and/or radium application. Only 11 cases were subjected to radical surgery. The over-all 5 year survival was 15 per cent. However, the results varied from 0 to 88 per cent when the sites of recurrences, initial stages, previous radiation factors, an...

Total brain irradiation of primary malignant brain tumors can be an acceptable solution to the problem of accurately localizing the anatomic limits of these tumors. Careful attention to the inferior border of the treatment field is necessary to avoid excluding the anterior-inferior temporal lobe. Exclusion of this region can result in therapeutic failure. A treatment field that employs easily palpable landmarks and includes the entire brain is suggested.

The purpose of this report is to call attention to the excellent response of two lymphosarcoma patients following total-abdomen irradiation, with emphasis on the remarkable complete regression of chylothorax in spite of the fact that no radiation was directed to the thorax. These cases are considered particularly noteworthy since, in reviewing the available literature, only a few cases of lymphosarcoma complicated by chylothorax with ascites and treated by abdominal irradiation could be readily found. Specifically, of these cases only brief mention was made in passing as to any favorable radiotherapeutic response related to the ascites. Of even greater significance was the paucity of information pertaining to either a favorable or an unfavorable response with respect to the associated chylothorax (6, 9, 11). Case Reports Case I: W. S., a 28-year-old Caucasian male, was transferred from an outlying military hospital to the U. S. Naval Hospital, San Diego, Calif., on April 15, 1965, with the diagnosis of ly...

A total of 219 patients with proved lung cancer were studied to determine whether post-resection irradiation improves survival. The results showed that postresection irradiation improved survival among patients with hilar and mediastinal lymph-node metastases of all histological types but did not improve survival among patients without node metastases. The authors recommend that patients with resectable lung cancer involving the hilar and mediastinal lymph nodes be treated by a combination of surgery and radiotherapy.

The incidence, severity, time of onset, and clinical course of complications of treatment have been reviewed in the RTOG studies of extended field irradiation in carcinoma of the prostate. A total of 526 patients, entered between 1976 and 1980 and followed for a minimum of 18 months, comprised the study population. In most instances of treatment-related morbidity, the symptoms were recorded during the first several months to 1 year following completion of treatment. Late occurrences, however, were not uncommon in certain types of radiation-produced injuries, such as proctitis, hematuria, and urethral strictures. Resolution of symptoms has been observed in a large proportion of patients including those with late occurrences of treatment-related morbidity, although the probability and the pattern of resolution differed considerably from one type of morbidity to another. Symptoms of cystitis are more likely to abate than those of proctitis. In patients who develop symptoms of proctitis the probability of persistence of symptoms beyond the second year following occurrence has been estimated at 20%–30%. Hematuria and symptoms secondary to urethral strictures seem to he even more likely to recur or persist, while genital and leg edema remain chronic in the majority of patients.

Results were evaluated for 651 consecutive patients with invasive cancer of the intact uterine cervix. From 1963 through 1967 319 patients were treated primarily with the older Los Angeles County Hospital system of orthovoltage radiation and intracavitary radium therapy. Thereafter, 1968--1974, 332 patients were treated primarily with a newer modified M. D. Anderson Tumor Institute system of megavoltage radiation and afterloading intracavitary radium therapy. Age distribution and histology were similar for both groups, but clinical stage was slightly more advanced for patients treated earlier. Crude and net 5 year survival rates were 36% and 49% for the early group and 54% and 67% for the later group. Net 5 year survival rates for the earlier group by stage were: stage I, 74%; II, 62%; III, 23%; and IV, 6%. Survival rates for the later group were: I, 81%; II 76%; III, 50%; and IV, 15%. We believe this improvement can be attributed to more effective intracavitary radium therapy for handling local cancer and to delivery of cancericidal doses of radiation to regional nodes with the megavoltage radiation apparatus, as well as to the greater cooperative efforts put forth in the management of County Hospital patients.

T he most effective cytoreductive agent known for treating cancer, short of the surgeon’s knife, is radiotherapy; however, all too often, surgery or radiotherapy or both can markedly reduce or completely eliminate a local tumor but still not save the patient with lung cancer. An analysis of 617 patients with lung cancer who were treated with radiotherapy and surgery has provided us some explanations for the dismal results with these methods, to which Morton et al (see page 640) and Holmes (see page 643) have alluded elsewhere in this symposium. Too often the radiotherapist may fail to appreciate the extent of the primary lesion and its likely nodal metastases and may be intimidated by the grim prognosis, so that he treats the patient with portals that are far too small and doses that are far too low to reasonably achieve more than limited palliation. For treatment with curative intent, it is important to administer the radiotherapy with adequate portals, which must include the nodal draining areas. Ordinarily, this means the mediastino-supraclavicular and cervical areas are to be included, along with radiation to the site of the primary neoplasm. Overlooked almost invariably in the past has been involvement in the upper abdomen and the epigastric area. Observations at surgery and at postmortem examination show a high percentage of involvement of the upper abdominal lymph nodes in patients with lung cancer, a percentage equal to or exceeding that in the cervical and supraclavicular areas. Lymphangiograms, arteriograms, and scanning with radioactive gallium help to tell us when to treat the upper abdomen. On the other hand, great care must be exercised when giving high doses to large portals, so that we do not exceed the patient’s tolerance to radiation. The problem centers on devising an optimum therapeutic regimen which produces a pattern of doses of radiation adequate to control the primary lesion and the disease in the nodes and yet does not exceed the tolerance of normal tissue. Hopefully, the treatment will not be worse than the disease and ideally should produce little, if any, adverse reactions and discomfort. One method of achieving ade

To determine the effect of low hemoglobin levels on the five-year survival rate, 700 patients with Stage I or II carcinoma of the cervix were studied. In 398 cases, primary radiotherapy was used; 181 had surgery alone, and 121 had surgery plus some irradiation. Initial hemoglobin levels were classed as ≤ 10, 10–13, and 13 g∕100 ml. A definite correlation exists between low initial hemoglobin levels and survival rate. Also, the larger the lesion, the lower the survival rate. Since correction of low initial hemoglobin levels did not significantly improve prognosis, tissue-induced anoxia as the ultimate single or major cause of poorer results is questioned.

A series of 790 patients with Stage I carcinoma of the corpus uteri, collected from 1940 to 1963, was divided into sets of prognostically distinct groups. The groups were arranged according to the patients age and histologic grade of their tumor. The uterine depth of the patients was used as well, where applicable. Within each group there was minimal variation in survival rates. The only major variable according to our data was therapy. Therefore, the relative merits of surgery and irradiation were readily comparable.Our study suggests that hysterectomy combined with irradiation (preoperative) appears to be the treatment of choice in Stage I cancer of the endometrium, except in the young patients with low grade tumors where surgery alone may suffice. In patients unable to withstand surgery, irradiation alone appears to be the treatment of choice.

The efficacy of radiotherapy in the management of pain caused by pancreatic carcinoma was assessed.Radiotherapy was infrequently employed to alleviate pain. However, when employed, radiotherapy almost uniformly alleviated pain at low dose levels that were well tolerated.The presence of liver metastasis did not interdict a favorable response.

Tumor response was assessed in 532 patients with epidermoid carcinoma of the uterine cervix. Tumor regression was estimated during weekly intervals up to eight weeks after the start of radiotherapy. Four response groups with distinct prognoses were identified: (a) excellent (75–100% tumor regression by the eighth week, 77-mo. median survival time); (b) good (50–75% tumor regression, 57-mo. median survival time); (c) fair (25–50% tumor regression, 29-mo. median survival time); and (d) poor (0–25% tumor regression, 17-mo. median survival time). Clinical staging and treatment factors contributed little that would explain this behavior. The significance of tumor response during radiotherapy is explained analytically. When tumor response is assessed during radiotherapy, a prognosis can be made.

The commonly used liver function tests are insensitive parameters of hepatic radiation response in the intact patient, particularly to treatment portals which include 50 per cent or less of the liver. This is due in part to their dependence, to a great degree, on the functional state of this organ as a whole. Symptoms due to liver irradiation are seldom encountered in practice, although the liver is included, in entirety or in part, in the treatment field during a course of radiotherapy for many abdominal, thoracic, or testicular malignant tumors. The apparent refractoriness of this organ to ionizing radiation in the usual clinical situation may be explained as follows: (a) the liver manifests nonsynchronous cyclic alterations of its cells in the mitotic phases, and the cells in the various stages of mitosis vary in radiosensitivity, (b) historically, the liver has been reputed to have enormous repair capacity following radiation injury (1), as well as after other forms of injury, and (c) the usual radiot...