Patterns of Recurrence in Retroperitoneal Liposarcomas: Reflecting Surgical Approach or Tumor Biology?

Abstract

Complete surgical resection remains the mainstay of curative treatment for retroperitoneal sarcomas (RPS) and provides the only hope for long-term survival. Unfortunately, the major mode of failure leading to poor outcome for retroperitoneal liposarcoma is intra-abdominal locoregional recurrence. The cause for the high rate of local recurrence following resection of retroperitoneal liposarcomas in contrast to limb sarcoma is customarily attributed to the specific anatomical site, containing vital neural and vascular structures, axial skeleton, and visceral organs limiting the ability to perform a wide resection. In addition, inherent tumor biology of liposarcomas has to be considered. The biological behavior of retroperitoneal liposarcomas are unpredictable. Clinically, some well-differentiated (WD) RPS behave in an indolent fashion over many years and never develop a dedifferentiated (DD) component. Other DD RPS develop de novo without a documented WD component. Some WD RPS can recur with a mainly DD component and vice versa. Although WD and DD RPS have a common genetic feature associated with genomic amplification which include amplification in 12q13-15 resulting in MDM2 and CDK4 overexpression, the specific genetic and molecular events leading to the unpredictable behavior is still not clear.

Treatment of patients with primary retroperitoneal sarcoma: predictors of outcome from an Australian specialist sarcoma centre

“…A recent analysis of 3141 RPS from the National Cancer Database in the USA found that high volume centres had a 2.5‐fold higher likelihood of receiving a R0/R1 resection ( P = 0.026) . This further supports recommendations that RPS be treated at specialist centres …”

Outcome following resection of retroperitoneal sarcoma

“…In the authors' opinion, a kidney preservation strategy should be cautioned if this compromises the quality of the initial operation. Performance of a piecemeal or R2 resection in order to preserve the kidney should be discouraged strongly.…”

Retroperitoneal Liposarcoma: Current Insights in Diagnosis and Treatment

“…Tseng and coworkers found that as many of 50% of patients with recurrent RLS presented with multifocal disease; importantly, type or extent of surgery did not predict recurrence outside of the resection field on univariate logistic regression analysis ( 37 ). Although tumor spill or incomplete resection may explain multifocal recurrence, it has been suggested that a “field change” of the entire intra-abdominal fat tissue may underly the observation of remote (out-of-field) recurrence ( 112 ). Genomic analyses of normal retroperitoneal fat as well as tumor samples may provide further insight into this phenomenon.…”