{'fraction_non_alphanumeric': 0.03373155305692199, 'fraction_numerical': 0.023893183415319746, 'mean_word_length': 4.836065573770492, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 1, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Reirradiation with local-field radiotherapy for painful bone metastases.

PURPOSE
The purpose of this study was to evaluate retrospectively the effectiveness, prognostic factors, and sequelae of the first course of local-field reirradiation for painful bone metastases.


PATIENTS AND METHODS
From 1994 to 2000, a total of 30 patients were reirradiated for painful bone metastases. The most commonly used initial treatment regimen was 30 Gy/10 Fr/2 wk. An additional dose in the range from 10 Gy/5 Fr to 26 Gy/13 Fr was reirradiated.


RESULTS
Fifteen patients (50%) showed some type of pain relief after reirradiation. Patients with initial CR were more likely to respond than those with previous PR (100% vs. 41%). The median duration of pain relief was five months. The duration of response was longer in initial CR than initial PR. The median survival time of responders after retreatment was 11 months. No patient developed radiation myelopathy. Prognostic factors for pain relief were duration from initial treatment, performance status (PS), and status of bone metastases.


CONCLUSION
Reirradiation for patients with a long duration from initial treatment (> or = 4 months), good PS (ECOG: 1-2), or solitary bone metastases was effective for pain relief. The appropriate indications, optimal dose, fractions, and technique for reirradiation to painful bone metastases should be further explored in randomized study.