Predicting outcome by growth rate of locally recurrent retroperitoneal liposarcoma: the one centimeter per month rule.

OBJECTIVE: To identify the prognostic variables that predict disease-specific survival and second local recurrence-free survival in patients with recurrent retroperitoneal liposarcoma so as to guide clinical management. SUMMARY BACKGROUND DATA: Local recurrence after complete resection of primary retroperitoneal liposarcoma is a common clinical problem that frequently leads to morbidity and mortality. Factors that determine survival in patients with a local recurrence after complete resection of the primary and rerecurrence after resection of the first local recurrence have not been clearly defined. METHODS: From a prospective sarcoma database we selected 105 patients who had at least one local recurrence following complete resection of a primary retroperitoneal liposarcoma between July 1982 and December 2005. Of these patients, 61 underwent complete resection of their first local recurrence. Study endpoints included second local recurrence-free survival for these 61 patients and disease-specific survival for all 105 patients. Univariate analysis was performed with the Kaplan-Meier method and log-rank test, and multivariate analysis with the Cox proportional hazards model and score test. Local recurrence growth rate was defined as the radiographic size of the local recurrence divided by the time to local recurrence from the primary resection. RESULTS: Median follow-up was 65 months. Local recurrence size, primary histologic variant and grade, and local recurrence growth rate were independent predictors of disease-specific survival. For those undergoing reresection, local recurrence size and local recurrence growth rate independently influenced development of a second local recurrence. Only patients with local recurrence growth rates of less than 0.9 cm/mo were associated with improved survival after aggressive resection of the local recurrence. CONCLUSIONS: Local recurrence growth rate is strongly associated with disease-specific survival and local control for patients with completely resected locally recurrent retroperitoneal liposarcoma. Despite aggressive operative management patients with a local recurrence growth rate greater than 0.9 cm/mo were associated with poor outcomes and should be considered for enrollment in clinical trials employing novel agents.

Giant retroperitoneal sarcomas: a single institution experience.

BACKGROUND: Retroperitoneal sarcomas (RS) are a rare group of malignant soft-tissue tumors; due to the flexibility of the retroperitoneum, they generally grow to a large size before becoming symptomatic, often involving surrounding structures. Therefore, the surgeon is frequently compelled to perform large excisions. The aim of this study is to assess clinical and pathological factors affecting prognosis in patients with RS who underwent surgical treatment, comparing giant forms (size > or = 25 cm) with smaller ones (size < 25 cm). METHODS: The hospital records of 73 consecutive patients who underwent surgical exploration for primary RS at our unit between 1984 and 2003 were reviewed. Statistical analysis of factors influencing overall and disease-free survival was performed including both the whole group of patients and only those who underwent complete surgical resection. RESULTS: Giant RS showed a lower resectability rate than smaller forms (54.2% vs. 84.2%, P = 0.005). In the group with complete surgical excision (51 out of 73), patients with giant RS had a higher rate of adjacent organ resection compared with the smaller ones (84.2% vs. 53.1%, P = 0.023). Tumor size did not influence prognosis: after complete resection, 5-year overall survival was 60.9% and 56.3% for giant RS and smaller forms respectively, while 5-year disease-free survival was 54.3% and 48.3% for the two groups respectively. Advanced stage, incomplete gross surgical resection, higher tumor grade, non-liposarcoma histology and microscopic infiltration of margins were found to be significantly negative prognostic factors. CONCLUSIONS: The present study confirms the importance of aggressive surgical management for RS, in order to offer these patients the best chance of long-term survival.