Fast neutron irradiation for locally advanced pancreatic cancer

Locally advanced pancreatic cancer: a review

It is anticipated that there will be 37,170 new cases of pancreatic cancer diagnosed in the United States this year, resulting in approximately 33,370 deaths from the disease. Approximately 40% of these patients will present with locally advanced, non-metastatic disease. Treatment regimens that incorporate conventional radiation therapy for local tumor control, and chemotherapy to prevent distant failure in this metastasis-prone malignancy, are the current standard of care. A number of clinical studies have been undertaken to establish the optimal definitive chemoradiation treatment in this setting. Other potential treatment strategies include chemoradiation incorporating novel chemotherapeutic agents, intraoperative radiation therapy, brachytherapy, and the integration of combined therapies that utilize targeted molecular agents. This review summarizes the current status, controversies, and future prospects for the treatment of locally advanced pancreatic cancer.

Le traitement par neutrons : hadronthérapie partie II : bases physiques et expérience clinique

Neutrons have radiobiological characteristics, which differ from those of conventional radiotherapy beams (photons) and which offer a theoretical advantage over photons to fight radioresistance by the differential relative biological effect of them between normal and tumour tissues. Neutron therapy beneficed of great interest between 1975 and 1985. Many of phase III trials were conducted and indications have been definitively deducted of them. After briefly describing the properties of neutron beams, this review discusses the indication of neutron therapy on the basis of the clinical results. Salivary, prostate tumours and sarcomas are the main indications of neutron therapy. In concern to the prostate cancers, other alternative treatments reduce the neutron therapy field. For sarcomas, the lack of randomised trials limits the impact of the interest of neutrons. For other tumours, the ratio benefice/risk of neutron therapy is inferior to these obtained with photons and they could not be considered like classical indications.

A multispecialty approach to the diagnosis and management of pancreatic cancer

This article reviews recent developments in pancreatic cancer research and offers a multispecialty perspective on the diagnosis and management of this challenging disease. Current findings in the molecular biology of the disease and their implications for management are examined, as well as development in diagnostic techniques, including helical computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangio-pancreatography (MRCP), and, particularly, endoscopic ultrasound-guided fine-needle aspiration. Surgical management, the role of adjuvant/neoadjuvant chemoradiation therapy, and the critical importance of accurate preoperative imaging are also addressed in this review. Palliative techniques, including endoscopic stenting for malignant obstructive jaundice and chemotherapy for locally advanced and metastatic disease, are discussed, and results of recent clinical trials in pancreatic cancer are summarized. Finally, future directions for research are identified.

Radiation therapy combined with Adriamycin or 5-fluorouracil for the treatment of locally unresectable pancreatic carcinoma. Gastrointestinal Tumor Study Group

One hundred fifty-seven patients with locally unresectable pancreatic carcinoma were randomly allocated to therapy with radiation and 5-fluorouracil or radiation and Adriamycin (doxorubicin). A total of 138 of 143 analyzable patients have died, and no differences in the relative survival impact of the treatments have been observed (P greater than 0.8). Toxicity on the Adriamycin arm was more substantial (P less than 0.05) and primarily attributable to Adriamycin chemotherapy after the completion of radiotherapy.

Response of pancreatic cancer to local irradiation with high-energy neutrons

Seventy-seven patients with locally advanced, nonresectable, biopsy-proven adenocarcinoma of the pancreas were treated by palliative bypass surgery followed by intensive neutron beam irradiation of the primary tumor site. Three dose levels, under 20, 21 to 23, and 24 to 25 Gy, were studied with the use of a treatment plan that included all known disease within a limited target volume, generally under 2 l. Symptomatic palliation was achieved in the majority of patients. The median survival time was 6 months. One patient remained alive and well without evidence of tumor 5 years after irradiation. Two were free of tumor at autopsy (one had died of intercurrent disease and one of radiation-related complications). A common cause of death was metastatic dissemination. Complication rates were dose-dependent; life-threatening complications did not exceed 12% with doses of less than 23 Gy. Autopsies from 19 patients were reviewed. In all, the pancreatic tumor site showed extensive reactive fibrosis. Local control was achieved in two patients, but most had both residual tumor in the pancreas and metastases. Six patients had centrolobular veno-occlusive liver disease. These patients had all received the higher (22-24 Gy) neutron doses. Six patients had hemorrhagic radiation gastroenteritis. Mild skin atrophy and bone marrow hypoplasia were seen in the irradiated volumes. The kidneys and spinal cord showed no radiation effects. The authors conclude that neutron irradiation can provide a good local response with marked regression and fibrosis of the tumor. This response, coupled with many deaths due to metastases, suggests that combined treatment with neutrons and chemotherapy would be worth exploring.

Therapy of gastrointestinal cancer

Cancer of the gastrointestinal tract represents a major international health problem. At the present time surgical resection for limited stages of disease represents the only treatment which can consistently provide long-term disease-free survival. Unfortunately, the majority of patients present with either microscopic metastatic disease in distant sites or advanced tumour growth which exceeds the limits of surgical resection. Relatively little progress has been made in the development of effective forms of non-surgical therapy. Gastric cancer, however, has been demonstrated to have greater sensitivity to forms of chemotherapy and radiation therapy than was previously appreciated. During the past decade, more effective forms of palliative therapy have been developed for patients with advanced disease, and approximately 15% of the cases with locally unresectable gastric cancer can now achieve long-term disease-free survival with combined forms of treatment. Unfortunately, similar progress has not been made in the management of pancreatic cancer or advanced colon cancer. The recent experience of the Gastrointestinal Tumor Study Group with the use of combined radiotherapy and chemotherapy for rectal cancer has demonstrated that improved disease-free survival can be achieved for patients with Dukes B and C disease. Overall, the current limited efficacy and considerable toxicity of conventional therapies strongly support the development of new approaches to the management of gastrointestinal cancer; this includes the exploitation of the recent progress that has been made in our understanding of cell proliferation and cell cycle control, and the importance of oncogenes and growth factors for regulation of these processes. Ultimately, our understanding of the molecular genetics of gastrointestinal cancer might allow for development of more effective means for both prevention and treatment at the molecular level.