Theoretic and Experimental Aspects of Regional Liver Infusion

Hepatic arterial infusion (HAI) with PEGylated liposomes containing 5-FU improves tumor control of liver metastases in a rat model

PURPOSE

To investigate the cytostatic effect of 5-fluorouracil (5-FU) encapsulated in polyethylene glycol (PEG) liposomes with or without degradable starch microspheres (DSM) in a long-term trial using a rat liver tumor model.

MATERIALS AND METHODS

The cytostatics were applied once either as a hepatic arterial infusion (HAI) or were systemically infused via the tail vein. Seven groups were compared with respect to tumor growth and survival times: 5-FU HAI (group I), 5-FU + DSM HAI (group II), PEG-5-FU HAI (group III), PEG-5-FU + DSM HAI (group IV), NaCl HAI (group V), 5-FU i.v. (group VI), and PEG-5-FU i.v. (group VII).

RESULTS

Seven and 14 days after treatment in groups III and IV, only group IV had significantly inhibited tumor growth on day 21 compared to the groups treated intravenously. On day 28, none of the animals from the intravenously treated groups were still alive compared to a significantly longer survival time of 6 and 8 weeks in groups III and IV.

CONCLUSION

Locoregional therapy with 5-fluorouracil encapsulated in PEGylated liposomes may further improve the treatment success with longer-lasting tumor regression and prolonged survival times.

Self assembled magnetic PVP/PVA hydrogel microspheres; magnetic drug targeting of VX2 auricular tumours using pingyangmycin

Chemotherapy in cancer treatment is associated with serious side effects and as a result there is great interest in research aimed at bringing down the level of systemic cytotoxicity. With advances in material science, magnetic drug targeting has emerged as one of the viable ways of attaining this. In this study, we used self assembled PVP/PVA magnetic hydrogel microspheres to deliver pingyangmycin (Bleomycin A5) to rabbit auricular VX2 tumours in the presence of a 0.5 T permanent magnet both during and 24 h after perfusion. A total of 22 New Zealand white rabbits ranging from 13 to 16 weeks and weighing 2.5-3.0 kg (2.46 +/- 0.2) successfully implanted with tumours 200-300 mm2 in size were used. In group D (1 mg pingyangmycin in 50 mg ferrofluid without a magnet) 2 weeks post treatment, there was statistically significant difference compared to the control (p = 0.05) in favor of group D. However, when compared to the group with 1 mg pingyangmycin(BLM) in 50 mg of ferrofluid and 0.5 mg (BLM) in 50 mg ferrofluid both with a permanent magnet in place for 24 h, the statistically significant difference was in favor of combined treatment, i.e. ferrofluid carrying drug in presence of a permanent magnet (p = 0.01). The microspheres in conjunction with the magnet did deliver pingyangmycin to the tumour and hence may be of use in future as far as magnetic drug targeting is concerned. However, more studies are still required to establish biodistribution and biostability not to forget drug release of ferrofluid of different chemotherapeutic agents available.

Hepatic arterial administration of activated leukocytes in patients with liver metastases

BACKGROUND

Liver is the most common site of metastatic disease. Hepatic arterial infusion (HAI) of cytotoxic drugs may achieve high objective response rate.

METHODS

Peripheral blood mononuclear cells were obtained by leukapheresis after stimulation with subcutaneous GM-CSF in six patients and with subcutaneous interleukin-2 (IL-2) in four patients, all with nonresectable hepatic metastases not responsive to conventional regimens. After the cytokine stimulation, the cells were administered by HAI either alone, or after HAI of melphalan (50 mg).

RESULTS

Mean number of 23.1 +/- 4.6 x 10(9) and 19.0 +/- 9.7 x 10(9) mononuclear cells were obtained through leukapheresis after GM-CSF and IL-2 priming, respectively. Significant cytotoxic activity was observed only after short IL-2 stimulation. A marked decrease in tumor markers was observed in two patients treated by combination of melphalan and activated leukocytes.

CONCLUSIONS

HAI is a technically feasible way of regional delivery of a high number of activated leukocytes obtained after short ex vivo activation.