Optimized procedure of real-time systemic leakage monitoring during isolated limb perfusion using a hand held gamma probe and 99mTc-HSA.

Isolated limb perfusion (ILP) therapy using a combination of tumour necrosis factor alpha (TNF) and cytostatic agents in hyperthermic conditions has proven to be effective in treating cancers limited to limbs or to a single organ such as the liver. A critical step for ILP is the accurate and real-time monitoring of that TNF toxic effects become relevant when overcoming the 10% limit of the 'effective' therapeutic dose administered during ILP. The most diffuse procedure for systemic leakage monitoring is based on the utilization of human soluble serum albumin (HSA) labelled with 131I and an external scintillation detector. In order to overcome some drawbacks connected with the properties of 131I, we developed a new procedure based on the utilization of HSA labelled with 99mTc in combination with a hand held gamma probe used as a detector. Our procedure consists of the following steps: (1) a 99mTc-HSA dose standardized as 0.5 MBq x kg(-1) body weight is injected into the ILP circuit before TNF administration; (2) a hand held gamma probe is placed over the pre-cordial area in a zone pre-marked on the patient's skin during a simulation test; (3) 48-72 h before ILP, a simulation test is obtained using a 99mTc-HSA dose corresponding to 10% of the dose calculated for ILP (i.e., 0.05 MBq x kg(-1) body weight); (4) during the simulation test the maximum count-rate zone detected on the pre-cordial area is marked on patient's skin; (5) a 60 min time-activity curve corresponding to the circulating 99mTc-HSA radioactivity effective decay is calculated and fitted; and (6) this time-activity curve is used to compensate for the leakage systemic counting observed during ILP. In order to compare the external, probe counting with the circulating radioactivity, in the first 10 patients from a total series of 43 treated patients, the results of external, probe monitoring were compared with the results of patient blood and perfusion circuit samples taken simultaneously every 5 min and measured by a laboratory gamma counter placed in the operating theatre. A good correlation was found between the two methods (R2 = 0.965, P < 0.01). It is concluded that the proposed procedure, based on the combination of 99mTc-HSA as the radiotracer and a hand held gamma probe as the detector, appears to be technically simple and accurate enough in the real-time monitoring of perfusion leakage in ILP cancer therapy. Moreover, using 99mTc-HSA as the radiotracer, the risk of radioactive contamination is significantly lower in comparison with 131I-HSA.

A simplified procedure for continuous intraoperative external monitoring of systemic leakage during isolated limb perfusion.

AIMS: Isolated limb perfusion (ILP) with high doses of an alkylating agent alone or in combination with tumor necrosis factor (TNF) in hyperthermic conditions (HAP) has been proposed for the treatment of locoregional tumors. A critical step in ILP/HAP is accurate monitoring of systemic leakage to prevent the toxic effects of chemotherapy, and in particular of TNF. Ten percent systemic leakage from the perfusion circuit is considered the maximum acceptable leakage. In this study we report our experience of a new leakage monitoring system. MATERIALS AND METHODS: Ths new simplified procedure is based on the use of 99mTc-labeled soluble human serum albumin (HSA) and a hand-held gamma probe as detector. The procedure consists of the following steps: 1) A standardized 99mTc-HSA dose of 0.5 MBq/kg body weight is injected into the perfusion circuit before chemotherapy/TNF perfusion and a hand-held gamma probe (IGP) is placed over the precordial area in a zone that was marked on the skin during a simulation test; 2) 48-72 hours before ILP/HAP a complete simulation test is performed with a 99mTc-HSA dose corresponding to 10% of the total dose calculated for the patient's body weight; 3) during the simulation test the maximum count-rate zone on the precordial area is detected by IGP and marked on the patient's skin; 4) a 60-min curve of effective 99mTc-HSA radioactivity decay (physical and biological) is calculated and fitted; 5) to compare external counting with the effective circulating radioactivity, patient blood samples and circuit blood samples are taken every five minutes during ILP/HAP and measured by a laboratory gamma counter and very convenient thanks to the favorable characteristics of IGP. The placed in the operating room. RESULTS: External counting with a hand-held gamma probe was easy to perform time/activity curves obtained during simulation tests showed a regular and constant effective decay with a mean decay rate of 30% at 60 minutes compared to baseline values. The external measurements obtained by IGP proved to be well correlated with blood samples measured in vitro by a laboratory gamma counter. The results of this procedure, in particular the data of the simulation test for each patient, allowed us to correct the limit of 10% maximum leakage during ILP/HAP in accordance with the time/activity curve. CONCLUSIONS: Although 99mTc-HSA has some unfavorable characteristics, it offers many advantages over 131I-HSA. The procedure proposed by us, which was based on the use of an IGP and 99mTc-HAS at a standardized dose of 0.5 MBq/kg body weight and on an individual simulation test for each patient performed 48 hours before ILP/HAP, proved to be simple and accurate in monitoring systemic leakage during ILP/HAP anti-cancer therapy.

Stop-flow technique for loco-regional delivery of antiblastic agents: literature review and personal experience.

AIMS: The therapeutic approach for primary or recurrent advanced solid tumours, particularly when unresectable, is still one of the main medical challenges in the management of cancer patients. The stop-flow (SF) technique has been recently proposed as a semi-invasive drug delivery system based on the blood supply blockage of the tumour-bearing area. Here, we discuss the principles underlying the SF technique as well as the worldwide experience published so far. We also report on the results of our pilot study on pelvic and limb SF perfusion. METHODS: We reviewed the worldwide experience on SF as reported by the literature published on PubMed from 1990 through 2001. In our series, we treated 20 patients affected with locally advanced melanoma, soft tissue sarcoma or colorectal cancer. RESULTS: This therapeutic modality - at least for some tumours - can achieve encouraging results in terms of clinical response even after conventional therapies have failed. Moreover, as a safe and relatively simple procedure, SF can be applied to patients for whom traditional treatments (i.e. surgery, systemic chemotherapy) are contraindicated because of poor general conditions. CONCLUSIONS: At present, the SF technique should be considered an investigational approach to locally advanced cancers. The encouraging results obtained with this procedure should be validated by large phase III trials.

Cytokine, infiltrating macrophage and T cell-mediated response to development of primary and secondary human liver cancer.

BACKGROUND: Kupffer cells, monocytes and infiltrating T cells have been considered the major source of interleukin-1beta and tumour necrosis factor-alpha in the liver. AIMS; To explore the expression of interleukin-1beta and tumour necrosis factor-alpha and to evaluate the density and the distribution of T lymphocytes and monocytes/macrophages in the liver of patients with primary and secondary tumours. METHODS: Tumoural and peritumoural liver samples were examined from 21 patients with hepatocellular carcinoma, 10 with hepatic metastases, 5 with benign focal liver lesions and 4 healthy adult livers. Interleukin-1beta and tumour necrosis factor-alpha mRNAs were detected by a semiquantitative comparative reverse transcriptase polymerase chain reaction. T lymphocytes and monocytes/macrophages were detected by immunohistochemistry. RESULTS: Higher levels of interleukin-1beta, tumour necrosis factor-alpha, CD3+ and CD68+ cells were found in the tissue surrounding hepatocellular carcinoma and metastases than in the tumour itself. A strong expression of CD68+ and CD3+ cells was found mainly along the tumour-host interface but the highest expression of CD3+ cells was found at the metastasis interfaces. Interleukin-1beta expression, CD3+ and CD68+ cell densities were higher in peritumoural samples than in so-called "normal" liver tissue. CONCLUSIONS: An increased production of interleukin-1beta and, to a lesser extent, of tumour necrosis factor-alpha mRNA coincides with the presence of cancer be it primary or secondary, both in healthy and cirrhotic livers. The presence of cancer, irrespective of the presence of underlying liver damage, appears to play the most important role.

Isolated vascular perfusion of human colon with adenocarcinoma.

Based on the premise that optimal drug delivery might improve the efficacy of locoregional treatment for solid tumors, the authors set up an experimental model for isolation perfusion in surgical specimens from patients resected for carcinoma of the colon. Ten surgical specimens were cannulated, washed internally and externally with saline solution, promptly cooled to 4 degreesC, connected to a circuit, and perfused with Krebs-Henselait modified solution, concentrated red blood cells, albumin, desamethasone, glucose, and heparin for 60 minutes at a target temperature of 37 degreesC. Organ temperature, flow rate, perfusion pressure, and metabolic and functional parameters were checked at 5, 20, and 60 minutes of perfusion. A paraphysiologic perfusion procedure was achieved. Mean values (and ranges) were as follows: temperature 37 degreesC (35. 1-39.6 degreesC); flow rate 10.2 (5.6-17.9) ml/min/100 g; arterial pressure 96 (42-154) mmHg; arterial pH 7.3 (7.1-7.5); arterial PO2 183 (78-304) mmHg; arterial PCO2 36 (31-46) mmHg. No important signs of tissue damage were found at histology. Autonomous or stimulated peristalsis (or both) was present throughout the experiment. Mean O2 extraction was 7.9 ml/min/100 g (range 3.1-11.0). Mean glucose consumption was 229 mg/100 g (range 174-252). The model worked well and appears promising, particularly for future use in various pharmacokinetic and pharmacodynamic studies of antiblastic agents.

Augmented membrane type 1 matrix metalloproteinase (MT1-MMP):MMP-2 messenger RNA ratio in gastric carcinomas with poor prognosis.

The activation of zymogen and the amount of proteinase and its inhibition are important in determining the eventual activity of matrix-degrading enzymes involved in tumor aggressiveness. To evaluate a gene complement leading to matrix metalloproteinase 2 (MMP-2; Mr 72,000 gelatinase) activity, membrane type 1 MMP (MT1-MMP), urokinase-type plasminogen activator, MMP-2, and tissue inhibitor of metalloproteinase 2 transcriptional levels were measured in gastric carcinoma biopsies. Comparative tumor:normal tissue reverse transcription-PCR in a cohort of 25 patients revealed up to a 10-fold difference in the expression of MT1-MMP, a metalloproteinase that has been proposed as a membrane receptor activator of MMP-2; a 1-unit increment resulted in a 30% risk to survival. A 20% risk also resulted from a 1-unit increment in the MT1-MMP: MMP-2 ratio, which showed differences of up to 15-fold. Instead, the expression of urokinase-type plasminogen activator, which trips off a cascade ending in the activation of MMP-2, as well as the expression of MMP-2 itself and its inhibitor, tissue inhibitor of metalloproteinase 2, lacked correlation with patient follow-up. Zymography revealed MMP-2 activities that were often in conflict with the transcription results and also with follow-up. The results suggest the evaluation of MT1-MMP and/or MT1-MMP:MMP-2 transcription as a new preoperative molecular-level prognostic factor for gastric carcinoma.