Patterns of Care Studies: Past, Present, and Future.

The Patterns of Care Study in Radiation Oncology (PCS) has existed for 25 years. This overview details the basic principles that have guided the study from its inception to the present and defines the future role for the PCS.

The Changing Structure of Radiation Oncology: Implications for the Era of Managed Care.

This report presents results from the facilities surveys that are useful for radiation oncology practices facing the challenges of managed care. Facilities surveys collect data from the entire census of facilities practicing megavoltage radiation therapy. Data include equipment, personnel, and patient load. The data presented show that most, but not all, facilities throughout the United States are adequately equipped in terms of highest energy treatment machine, type of treatment planning computer, simulation, and quality assurance programs. The data also present the variation in percentage of new cancer cases receiving radiation therapy and repeat patients as a percentage of new radiation therapy cases by census region. The data show trends in patient load per type of personnel for academic, hospital-based, and freestanding facilities in 1994 show that academic facilities are larger and treat more patients per treatment machine. Academic facilities used more therapists per machine than other facilities.

Quality Assessment in the USA: How the Patterns of Care Study Has Made a Difference.

Improving the quality and accessibility of radiation care in the United States has been the primary objective of the Patterns of Care Study (PCS) since its inception. While patient care has two components, technical and interpersonal, the PCS has only studied the quality of technical care. Such assessments of technical quality of radiation oncology, which are representative of the United States as a whole, virtually do not exist outside those of the PCS. The methodology used by the PCS to assess quality in radiation oncology is based on an examination of structure, process, and outcome. Structural elements identified by the PCS to be associated with inferior quality include the use of a Cobalt 60 unit with surface-to-skin distance (SSD)

Clinical Applications of Picture Archival and Communications Systems in Radiation Oncology.

Picture archival and communications systems (PACS) for radiation oncology present an entirely different set of constraints and requirements from systems developed for diagnostic imaging. PACS for radiation oncology aid in organizing the complex, interrelated functions of radiation oncology. Integration of PACS with clinical data management systems will provide the backbone for the comprehensive computer system that has long been sought in radiation oncology. Simulation, geometric and dosimetric treatment planning, field shaping, set-up, verification, and delivery are now all observable and/or controllable from computer systems that can be interfaced with the departmental PACS. Costs are substantially lower than with diagnostic PACS because the systems can be based on desktop computers and the image resolution requirements are not as stringent. Each PACS user will have more information more easily available than under current systems of organization. Vendor support of digital image communications (DICOM) protocols will enable full integration of equipment regardless of manufacturer. Potential increased in productivity will be realized if the systems for handling and evaluating images are fully automated and provide the users with analytic tools that enhance the utility of systems such as electronic portal imagers, multileaf collimators, and clinical data management systems. this report describes our efforts in producing such a system.

Chemoradiation: A Superior Alternative for the Primary Management of Esophageal Carcinoma.

There have been no randomized studies of esophagectomy versus chemoradiation as primary management of esophageal cancer. Review of the literature indicates esophagectomy alone has limited applicability, significant morbidity, higher mortality, and a lesser chance for cure than chemoradiation for patients with squamous cell cancer of the esophagus. The majority of patients with esophageal cancer have disease extending through the esophageal wall or nodal involvement and the prognosis for such patients treated by esophagectomy alone is quite poor, with 5-year survival rate of 10% or less. Recent studies indicate 5-year survival rates with chemoradiation is 20% to 25%. Local failure rates are similar with chemoradiation versus esophagectomy, but swallowing function is superior with chemoradiation. Salvage surgery is possible following chemoradiation for the small percentage of patients who have local-only failure. Chemoradiation is preferred to esophagectomy for patients with squamous cell cancer of the esophagus, and offers significant palliation and the chance for cure for patients with adenocarcinoma of the esophagus as well.

Palliative Treatment of Esophageal Cancer.

Palliative interventions for advanced esophageal cancer include surgery, radiation therapy, chemotherapy, chemoradiation, endoscopic procedures, and combinations of the above. Palliative esophagectomy or bypass procedures are difficult to justify in these patients because their life expectancy is so short. Palliative external beam radiation to doses of 50 to 60 Gy is successful in 50% to 70% of patients. The addition of brachytherapy may improve these results. One third to one half of patients treated with radiation develop benign or maglinant stricture. Although response rates to combination chemotherapy are only 50% at best, the majority of patients do have improvement of dysphagia. These regimens are commonly used as part of a multidisciplinary approach with radiation andøor surgery, rather than as a sole modality of treatment. Chemoradiation regimens results in better survival than treatment with radiation alone, and provide palliation of dysphagia in up to 90% of patients. Although acute toxicity of chemoradiation is more severe than radiation alone, this is of limited duration. Chemoradiation may be the treatment of choice for the majority of patients with locally advanced esophageal cancer. Endoscopic techniques are available that provide palliation of dysphagia. The most commonly used technique is esophageal dilatation, either alone or before performing other palliative procedures such as laser therapy or stent placement. The most significant limitation of dilatation alone is that palliation is short-lived and most patients require repeat dilatations. Esophageal stents offer a high degree of palliation, but procedure-related morbidity and mortality rates are not insignificant. Expandable metal stents are associated with few complications but tumor ingrowth through the metallic mesh is frequent. Conventional plastic stents are not affected by tumor ingrowth but can migrate. Endoscopic laser therapy also provides symptoms relief and complication rates are relatively low. It is possible that a combination of laser therapy and external beam or intraluminal radiation will provide more durable palliation than laser treatment alone. BICAP tumor probes, (Circon-ACMI, Stamford, CT), which provide direct application of electrical current, are limited to treatment of tumors that are circumferential. Photodynamic therapy (PDT), which applies laser light along with a photosensitizing agent, has resulted in a high rate of palliation. Limitations of PDT include skin photosensitization requiring patients to stay out of the sun for at least 1 month following treatment, high cost of required equipment, and limited efficacy because of the shallow depth of light penetration. A variety of treatment options exist for the management of tracheoesophageal fistulae (TEF), but only radiation therapy or bypass surgeyr appear to prolong survival. Radiation therapy does not appear to worsen the TEF as was commonly thought in the past, and it is likely applicable in more patients than is surgery. The challenge for the physician in palliating patients with esophageal cancer is to select therapy appropriate for a given patient, taking into account the patient's disease, coexisting medical problems, performance status, and the patient's desires.