An Initial Report of a Radiation Dose-Escalation Trial in Patients with One to Five Sites of Metastatic Disease

Abstract

Purpose: Previous investigations have suggested that a subset of patients with metastatic cancer in a limited number of organs may benefit from local treatment. We investigated whether cancer patients with limited sites of metastatic disease (oligometastasis) who failed standard therapies could be identified and safely treated at one to five known sites of low-volume disease with radiotherapy. Experimental Design: Patients with one to five sites of metastatic cancer with a life expectancy of >3 months and good performance status received escalating doses of radiation to all known sites of cancer with hypofractionated radiation therapy. Patients were followed radiographically with computed tomography scans of the chest, abdomen, and pelvis and metabolically with [ 18

Prognostic impact of M descriptors of the 8th edition of TNM classification of lung cancer

“…The European Society for Medical Oncology states that oligometastases are defined as at maximum five metastatic lesions in the body (8). However, some studies found that patients with 1 or 2 lesions had significantly better survival than those with 3 to 5 metastatic lesions (9). In our study, the OS of patients with two lesions in a single organ was not statistically inferior to OS of patients with a single lesion in a single organ (P=0.180).…”

“…One of the possible explanations for this result is that in our study 70% of patients with multiple metastases in a single organ had 5 or less metastases. According to some authors, this could be considered oligometastases and could be associated to a better prognosis (8,9). This finding of our study raises the question whether patients with few metastases in a single organ should be included in M1c category.…”

Radiotherapy Promotes Tumor-Specific Effector CD8+ T Cells via Dendritic Cell Activation

“…This may also explain why repeated radiotherapy is less immuno-supportive than a single dose (15)(16)(17)(18)(19)(20).…”

“…The recent advances in radiotherapy allow the use of high-dose irradiation as part of stereotactic radiotherapy while minimizing adverse side effects. Clinical evidence shows that patients treated with one to two high doses of radiotherapy respond better than those treated with fractionated low-dose radiotherapy, and the involvement of other mechanisms than direct killing of tumor cells has been suggested (15)(16)(17)(18). It was shown recently that single highdose radiotherapy but not fractionated low-dose radiotherapy increased accumulation of CD8 + T cells in the tumor (19), crucially depended on CD8 + T cells (20), and resulted in the generation of tumor-specific CTLs (21).…”

Blockade of Tumor Necrosis Factor α Signaling in Tumor-Associated Macrophages as a Radiosensitizing Strategy

“…In some selected lung cancers, or limited forms of metastasis, very large doses (one to five treatments of 10-20 Gy) may be used (1). Despite research into the radiobiology and physics of radiotherapy, many patients fail within the irradiated target volume.…”