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Isolated limb perfusion (ILP) with melphalan and tumor necrosis factor (TNF)-α is used to treat bulky, locally advanced melanoma and sarcoma. However, TNF toxicity suggests a need for better-tolerated drugs. Cilengitide (EMD 121974), a novel cyclic inhibitor of alpha-V integrins, has both anti-angiogenic and direct anti-tumor effects and is a possible alternative to TNF in ILP. In this study, rats bearing a hind limb soft tissue sarcoma underwent ILP using different combinations of melphalan, TNF and cilengitide in the perfusate. Further groups had intra-peritoneal (i.p.) injections of cilengitide or saline 2 hr before and 3 hr after ILP. A 77% response rate (RR) was seen in animals treated i.p. with cilengitide and perfused with melphalan plus cilengitide. The RR was 85% in animals treated i.p. with cilengitide and ILP using melphalan plus both TNF and cilengitide. Both RRs were significantly greater than those seen with melphalan or cilengitide alone. Histopathology showed that high RRs were accompanied by disruption of tumor vascular endothelium and tumor necrosis. Compared with ILP using melphalan alone, the addition of cilengitide resulted in a three to sevenfold increase in melphalan concentration in tumor but not in muscle in the perfused limb. Supportive in vitro studies indicate that cilengitide both inhibits tumor cell attachment and increases endothelial permeability. Since cilengitide has low toxicity, these data suggest the agent is a good alternative to TNF in the ILP setting., (Copyright © 2012 UICC.)

Background: Isolated hepatic perfusion with high-dose chemotherapy is a treatment option for patients with irresectable metastases confined to the liver. Prolonged local control and impact on survival have been claimed. Major drawbacks are magnitude and costs of the procedure. We developed an isolated hypoxic hepatic perfusion (IHHP) with retrograde outflow without the need for a heart-lung machine., Patients and Methods: Twenty-four consecutive patients with irresectable metastases of various origins were treated. IHHP inflow was via the hepatic artery, outflow via the portal vein with occlusion of the retrohepatic caval vein. Radiolabeled albumine was used for leakage monitoring. Melphalan was used at 1-2 mg/kg. A 25-minute perfusion period was followed by a complete washout. Local and systemic melphalan concentrations were determined., Results: Compared with oxygenated classical IHP, the IHPP procedure reduced operation time from >8 h to 4 hours, blood loss from >4000 to 900 cc and saved material and personnel costs. Leakage was 0% with negligible systemic toxicity and 0% perioperative mortality. Tumor response: complete response (CR) in 4%, partial response (PR) in 58%, and stable disease (SD) in 13%. Median time to progression was 9 months (2-24 months); pharmacokinetics demonstrated intrahepatic melphalan concentrations more than 9 fold higher than postperfusion systemic concentrations., Conclusions: IHPP is a relatively simple procedure with reduced costs, reduced blood loss, no mortality, limited toxicity, and response rates comparable to classic IHP. The median duration of 9 months of tumor control should be improved. Hereto, vasoactive drugs, will be explored in further studies.

Aims: To investigate the feasibility of hypoxic pelvic perfusion (HPP), using balloon catheter techniques as treatment modality for locally advanced pelvic malignancies., Methods: In a phase I--II study, 16 patients with various non-resectable pelvic tumours were treated with two HPP with MMC and melphalan, followed by radiotherapy (25 Gy) and surgical resection if feasible. Toxicity and procedure related complications were documented. Tumour responses were assessed by MRI or CT. Pain reductive effects were assessed by evaluation of pain registration forms., Results: HPP resulted in augmented regional drug concentrations with relatively low systemic levels. Some severe systemic toxicity was observed. One procedure related death occurred. Pain reduction effects were short-lived. Ten patients had radiological NC, two PD and one PR. In 11 patients surgical resection was performed, which was microscopically radical in six cases. Mean survival was 26.8 months (range 1--86)., Conclusion: The seemingly favorable pharmacokinetic profiles observed with HPP in this and other studies can still lead to severe systemic toxicity. In terms of survival, local (re-)recurrence and pain reduction there seems no benefit of addition of HPP to pre-operative radiotherapy. HPP with MMC and melphalan, does not seem a therapeutic option in patients with locally advanced pelvic tumours.

Background: We have previously shown how tumor response of isolated limb perfusion (ILP) with melphalan was improved when tumor necrosis factor alpha (TNF-alpha) was added. Taking into account that other vasoactive drugs could also improve tumor response to ILP, we evaluated histamine (Hi) as an alternative to TNF-alpha., Methods: We used a rat ILP model to assess the combined effects of Hi and melphalan (n = 6) on tumor regression, melphalan uptake (n = 6), and tissue histology (n = 2) compared with Hi or melphalan alone. We also evaluated the growth of BN-175 tumor cells as well as apoptosis, necrosis, cell morphology, and paracellular permeability of human umbilical vein endothelial cells (HUVECs) after Hi treatment alone and in combination with melphalan., Results: The antitumor effect of the combination of Hi and melphalan in vivo was synergistic, and Hi-dependent reduction in tumor volume was blocked by H1 and H2 receptor inhibitors. Tumor regression was observed in 66% of the animals treated with Hi and melphalan, compared with 17% after treatment with Hi or melphalan alone. Tumor melphalan uptake increased and vascular integrity in the surrounding tissue was reduced after ILP treatment with Hi and melphalan compared with melphalan alone. In vitro results paralleled in vivo results. BN-175 tumor cells were more sensitive to the cytotoxicity of combined treatment than HUVECs, and Hi treatment increased the permeability of HUVECs., Conclusions: Hi in combination with melphalan in ILP improved response to that of melphalan alone through direct and indirect mechanisms. These results warrant further evaluation in the clinical ILP setting and, importantly, in organ perfusion.

Background: Isolated hepatic perfusion for irresectable metastases confined to the liver has reported response rates of 50% to 75%. Magnitude, costs, and nonrepeatability of the procedure are its major drawbacks. We developed a less invasive, less costly, and potentially repeatable balloon catheter-mediated isolated hypoxic hepatic perfusion (IHHP) technique., Methods: In this phase I and II study, 18 consecutive patients with irresectable colorectal or ocular melanoma hepatic metastases were included. Two different perfusion methods were used, both with inflow via the hepatic artery, using melphalan 1 mg/kg. In the first eight patients, the portal vein was occluded, and outflow was via the hepatic veins into an intracaval double-balloon catheter. This orthograde IHHP had on average 56% leakage. In next 10 patients, we performed a retrograde outflow IHHP with a triple balloon blocking outflow into the caval vein and allowing outflow via the portal vein. The retrograde IHHP still had 35% leakage on average., Results: Although local drug concentrations were high with retrograde IHHP, systemic toxicity was still moderate to severe. Partial responses were seen in 12% and stable disease in 81% of patients. The median time to local progression was 4.8 months., Conclusions: We have abandoned occlusion balloon methodology for IHHP because it failed to obtain leakage control. We are presently conducting a study using a simplified surgical retrograde IHHP method, in which leakage is fully controlled, which translates into high response rates.

Isolated hepatic perfusion (IHP) with melphalan with or without tumour necrosis factor alpha (TNF-alpha) is currently performed in clinical trials in patients with hepatic metastases. Previous studies led to the hypothesis that the use of TNF-alpha in isolated limb perfusion causes specific destruction of tumour endothelial cells and thereby induces an increased permeability of tumour vasculature. However, whether TNF-alpha contributes to the therapeutic efficacy in IHP still remains unclear. In an in vivo rat liver metastases model we studied three different tumours: colon carcinoma CC531, ROS-1 osteosarcoma and BN-175 soft-tissue sarcoma which exhibit different degrees of vascularisation. IHP was performed with melphalan with or without the addition of TNF-alpha. IHP with melphalan alone resulted, in all tumour types, in a decreased growth rate. However in the BN-175 tumour addition of TNF-alpha resulted in a strong synergistic effect. In the majority of the BN-175 tumour-bearing rats, a complete response was achieved. In vitro cytoxicity studies showed no sensitivity (CC531 and BN-175) or only minor sensitivity (ROS-1) to TNF-alpha, ruling out a direct interaction of TNF-alpha with tumour cells. The response rate in BN-175 tumour-bearing rats when TNF-alpha was coadministrated with melphalan was strongly correlated with drug accumulation in tumour tissue, as only in these rats a five-fold increased melphalan concentration was observed. Secondly, immunohistochemical analysis of microvascular density (MVD) of the tumour showed a significantly higher MVD for BN-175 tumour compared to CC531 and ROS-1. These results indicate a direct relation between vascularity of the tumour and TNF-alpha mediated effects. Assessment of the tumour vasculature of liver metastases would be a way of establishing an indication for the utility of TNF-alpha in this setting.

Objective: The influences of flow, perfusion time, and concentration on melphalan (MN) lung levels in a rat model of isolated lung perfusion (ILuP) were studied., Methods: ILuP was performed in WAG/Rij rats by using a single-pass system with 0.5, 0.05, 0.01, and 0.005 mg of MN. Subsequently ILuP with 0.05 mg MN was performed during 30 min with a flow rate of 0.5 ml/min, during 60 min with a flow rate of 0.5 ml/min, and during 30 min with a flow rate of 1.0 ml/min., Results: The lung MN levels of 0.05 mg were significantly lower as compared with 0.5 mg (p = 0.02). In the second experiment, no significant differences were seen in lung levels of MN between the different groups., Conclusion: The final lung MN levels were only determined by the absolute amount administered., (Copyright 2003 S. Karger AG, Basel)

Many tumors are impervious to anticancer agents. Resistance due to lack of cytotoxic penetration into the tumor is often overlooked but can play a significant role in undermining therapy. Insufficient and irregular vascularization of tumors is a possible barrier to drug delivery, but there are others, e.g., impaired vessel permeability and poor interstitial transport. We evaluated the importance of tumor vessel density in the availability of melphalan to tumors. A nude mouse tumor model with different vascularization due to a single-gene deletion of hypoxia-inducible factor 1alpha (HIF-1alpha(+/+) and HIF-1alpha(-/-) embryonic stem cell-derived tumors) was used. The availability of melphalan to HIF-1alpha(+/+) (n = 20) and HIF-1alpha(-/-) (n = 23) tumors was not significantly different (p = 0.12). Furthermore, in the various subgroup analyses accentuating the difference in vessel density, no significant correlation between vessel density and melphalan availability was found. In the second part of the study, melphalan, was demonstrated to be transported in blood in mice with a distribution of 24% in erythrocytes vs. 76% in plasma. A strong correlation (r = 0.93, p < 0.000001) between melphalan concentrations in plasma and erythrocytes was found, indicating an equilibrium between these 2 compartments. Plasma and erythrocyte concentrations of melphalan are correlated with the tumor availability of melphalan (r = 0.66 and 0.64, respectively, both p < 0.001). These data suggest that tumor vessel density is not an important predictor of the tumor availability of small cytotoxic drugs such as melphalan and indicate the importance of erythrocytes in the transport of melphalan., (Copyright 2002 Wiley-Liss, Inc.)

Background/aims: The success of and our extensive experience with TNF alpha-based isolated limb perfusions in patients with unresectable extremity soft tissue sarcomas made us explore the possibilities for a similar approach for the treatment of hepatic metastases. After experience with the classic surgical isolated hepatic perfusion in pigs and in patients, we concluded that the classic surgical approach was associated with serious drawbacks i.e., magnitude of the procedure with morbidity, lack of repeatability of the procedure, complexity and costs. These problems were addressed in a program aimed at developing a repeatable method of isolated perfusion of the liver with minimally invasive techniques., Methodology: We validated the methodology of isolated hypoxic hepatic perfusion using balloon catheter techniques in pigs., Results: The excellent pharmacokinetic profile of the procedure, resulting in very high regional drug concentrations and negligible systemic drug concentrations, allowed us to move on to the clinic and start to study and further develop this method in a phase I-II study using the drug melphalan, in patients with irresectable hepatic metastases., Conclusions: We aim to develop step by step a fully percutaneous approach for isolated hypoxic hepatic perfusion.

Several possible mechanisms for the synergistic anti-tumour effects between tumour necrosis factor alpha (TNF-alpha) and melphalan after isolated limb perfusion (ILP) have been presented. We found a significant sixfold increase in melphalan tumour tissue concentration after ILP when TNF-alpha was added to the perfusate, which provides a straightforward explanation for the observed synergism between melphalan and TNF-alpha in ILP.

Purpose: Oxazaphosphorines are metabolised by a variety of pathways, one of which leads to activation and the formation of alkylating compounds. However, the transport forms conveying activated oxazaphosphorines to the tumour cell have not been fully characterised. There is increasing recognition of the importance of the erythrocyte as a carrier of compounds in the circulation, and we have recently described higher concentrations of 4-hydroxycyclophosphamide within the erythrocyte compartment compared to plasma. We have now determined the concentrations of ifosfamide and seven of its metabolites in the plasma and erythrocytes of patients receiving a six-hour intravenous infusion of ifosfamide., Patients and Methods: Red cells from five patients, receiving a total of eight cycles of ifosfamide, were separated from plasma using the MESED instrument, and analysis of red cells and plasma performed using Gas Chromatography-Mass Spectrometry (GC/MS)., Results: The concentration of all compounds in the erythrocyte compartment was higher than or equal to those in plasma, and isophosphoramide mustard and carboxyifosfamide showed a particular affinity for the erythrocyte. The red cell fraction can contain as much as 77% of the total blood concentration of isophosphoramide mustard., Conclusions: Erythrocyte associated isophosphoramide mustard is an important transport form of activated ifosfamide. Red cells may have a role in the delivery of activated oxazaphosphorines to tissues.