Revolutionizing the treatment of locally advanced extremity soft tissue sarcomas: a review on TNFα-based isolated limb perfusion

The Use of Regional Anesthesia to Reduce Blood Loss in Isolated Limb Perfusion (ILP)-A Novel Approach

BACKGROUND

Isolated limb perfusion (ILP) for soft tissue sarcomas (STS) is usually performed with tumor necrosis factor alpha (TNF-α) and melphalan. ILP regularly leads to a total blood loss (BLt) of 1.5-2 L/patient. Blood inflow from the central blood circulation to the limb is influenced by unstable pressure gradients and pain reactions after the administration of melphalan. With perioperative regional anesthesia (RA), pain levels can be reduced, and the pressure gradient stabilized resulting in a reduced BLt. The aim of this study was to compare the BLt with and without RA in patients with ILP during circulation of drugs.

METHODS

Patients were treated according to the following protocol: After the establishment of limb circulation, ILP was started with the administration of TNF-α. Half the dose of melphalan was given as a bolus after 30 min, and the remaining dose was continuously administered in the following 30 min. The extremity was washed out after 90 min. ILP with perioperative RA (supraclavicular plexus block/peridural catheter) was performed prospectively in 17 patients and compared to a matched retrospective control group of 17 patients without RA. BLt was documented and perioperative anesthesiological data were analyzed for response rates after the application of melphalan (RaM).

RESULTS

BLt and RaM tended to be lower for the intervention group with RA if compared to the control group without RA in all analyses. The trend of lower BLt and RaM in ILP with RA was more pronounced for the upper extremity compared to the lower extremity. Results were not statistically significant.

CONCLUSION

These findings indicate that the use of RA can help to stabilize hemodynamic anesthetic management and reduce the BLt in ILP, especially during perfusion of the upper extremities.

Histological response assessment following neoadjuvant isolated limb perfusion in patients with primary, localised, high-grade soft tissue sarcoma

PURPOSE

Histological response assessment following neoadjuvant treatment can help identify patients at a higher risk for systemic disease progression. Our goal was to evaluate whether mitotic count and the amount of viable tumour following neoadjuvant isolated limb perfusion (ILP) for primary, locally advanced, non-metastatic, high-grade extremity soft tissue sarcoma correlate with prognosis.

PATIENTS AND METHODS

This study is a retrospective analysis of 61 patients who underwent neoadjuvant ILP followed by surgical resection with curative intent between 2001 and 2011. Non-parametric analyses were carried out with the Mann-Whitney U and the Wilcoxon signed-rank test. Survival curves were calculated with the Kaplan-Meier method and compared with the log-rank test.

RESULTS

The median follow-up was 44 months for all patients and 55 months for survivors. The amount of viable tumour after ILP had no correlation with overall (OS) (P = 0.227) or event-free (EFS) (P = 0.238) survival probability. Patients with a low mitotic count after ILP had a significantly higher OS (P < 0.001), EFS (P = 0.002) and post-relapse survival probability (P = 0.030) compared to patients with an intermediate or high mitotic count.

CONCLUSIONS

The mitotic count following ILP for primary, high-grade, locally advanced, non-metastatic soft tissue sarcoma appears to significantly correlate with prognosis. If these results are validated in a prospective setting, they could provide a rationale for the design of adjuvant systemic chemotherapy trials with the goal of improving the prognosis of patients with an intermediate or high mitotic count after ILP.

Prognostic relevance of ¹⁸F-FDG PET uptake in patients with locally advanced, extremity soft tissue sarcomas undergoing neoadjuvant isolated limb perfusion with TNF-α and melphalan

PURPOSE

The objective of this study was to determine whether (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) can adequately assess the risk of systemic disease progression in patients with primary, localized, high-grade soft tissue sarcomas of the extremities undergoing neoadjuvant isolated limb perfusion (ILP) with tumour necrosis factor and melphalan.

METHODS

This was a retrospective analysis of the files of 35 patients who underwent a PET or PET/CT scan prior to and after ILP followed by surgical resection with curative intent between 2006 and 2012. SUVmax₁ was defined as the maximum standardized uptake value (SUV) at diagnosis, SUVmax₂ as the maximum SUV after ILP and ΔSUVmax as the percentage difference between SUVmax1 and SUVmax₂.

RESULTS

The median follow-up was 40 months for all patients. The median SUVmax1 amounted to 7.6, while the median SUVmax₂ was 4.7. The median ΔSUVmax was -44%. Overall survival (OS) probability at 2 and 5 years amounted to 78 and 70%, respectively, while metastasis-free survival (MFS) probability at 2 and 5 years was 67 and 64%, respectively. Receiver-operating characteristic (ROC) curve analysis showed that both SUVmax2 and ΔSUVmax could predict systemic disease progression, while SUVmax1 could not adequately identify patients who went on to develop metastatic disease. The optimal cut-off value was 6.9 for SUVmax2 and -31 % for ΔSUVmax. Patients with an SUVmax2 <6.9 had a 2-year MFS of 80%, compared to 31 % for patients with an SUVmax2 ≥ 6.9 (p < 0.001). Patients with a ΔSUVmax < -31 %, i.e. patients with a higher metabolic response, had an MFS of 76% at 2 years, compared to 42% for patients with a ΔSUVmax ≥ -31% (p = 0.050).

CONCLUSION

SUVmax after ILP for primary, locally advanced, non-metastatic high-grade soft tissue sarcomas of the extremities appears to be significantly correlated with prognosis. Whether patients with a high SUVmax after ILP will benefit from standard or experimental adjuvant systemic treatment options should be evaluated in future studies.