{'fraction_non_alphanumeric': 0.036511156186612576, 'fraction_numerical': 0.02535496957403651, 'mean_word_length': 4.669540229885057, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, '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}}
Multifactorial analysis of long-term follow-up (more than 5 years) of primary extremity sarcoma.

BACKGROUND
The majority of survival studies in patients with extremity soft tissue sarcoma have focused on early recurrence and mortality. There are few data addressing long-term follow-up and survival.


OBJECTIVE
To analyze survival and recurrence in patients with extremity soft tissue sarcoma who survive for more than 5 years.


METHODS
Patients who underwent treatment for primary tumors (July 1982 to July 1994) and were followed up for more than 5 years were the subject of study. Disease-specific and disease-free survival were determined actuarially. Significance was evaluated using log-rank testing for univariate analysis and Cox model stepwise regression for multivariate analysis.


RESULTS
A total of 495 patients with primary extremity tumors were treated before July 1989 and eligible for 5-year follow-up. Of these, 282 have been followed up for more than 5 years (median follow-up, 84.4 months). Actuarial disease-specific survival of patients who survive for longer than 5 years was 79%+/-7% (+/-SEM) at 10 years, and of those who were metastasis free at 5 years was 91%+/-4% at 10 years. On univariate analysis, post-5-year disease-specific survival was influenced by positive microscopic margin and initial tumor size of 5 cm or greater. On multivariate analysis, post-5-year disease-specific survival was influenced only by positive margins.


CONCLUSIONS
Based on these analyses, 21% of patients with primary extremity sarcoma who survive for 5 years will die of disease within 5 years. Even of those who are metastasis free at 5 years, 9% will die of disease within 5 years. In contrast to early mortality, tumor grade has no influence on post-5-year prognosis. Patients with positive microscopic margins are at risk for post-5-year disease-specific mortality and therefore require long-term follow-up and consideration for investigational therapy.