Shock wave and THP-adriamycin for treatment of rabbit's bladder cancer

[Organ-sparing treatment of bladder cancer]

BACKGROUND

Muscle invasive bladder cancer is a frequent disease in Germany. The accepted therapy of choice is radical cystectomy. Due to comorbidities, radical removal of the bladder is often associated with increased perioperative morbidity; therefore alternatives to a radical procedure should be offered.

OBJECTIVES

Overview and description of focal therapeutic concepts in muscle invasive bladder cancer to provide therapeutic alternatives for radical organ removal.

MATERIALS AND METHODS

Database research, analysis and discussion of clinical trials presenting therapeutic concepts for focal therapy in muscle invasive bladder cancer.

RESULTS

High-energy shock waves, high-intensity focused ultrasound and laser therapy are experimental concepts for muscle invasive bladder cancer. Transurethral resection and radiotherapy in combination with chemotherapy, where appropriate, are available as focal therapy in bladder cancer.

CONCLUSIONS

Cystectomy is the accepted therapy for muscle invasive bladder cancer. Several therapeutic procedures are available as focal therapy. In selected cases, focal therapy can offer an alternative therapy in muscle invasive bladder cancer.

Lithotripter shockwave-induced enhancement of mouse melanoma lung metastasis: dependence on cavitation nucleation

PURPOSE

To confirm a previous report of metastasis enhancement by lithotripter shockwaves (LSW) and to test the hypothesis that this effect is attributable to cavitation.

MATERIALS AND METHODS

The metastatic B16-D5 melanoma cell line was implanted on the hind legs of female C57/b16 mice 12 days before tumor treatment. The tumors were treated with 500 LSW in a waterbath arrangement. The effect of augmented cavitation nucleation was tested by intratumor injection of air bubbles or ultrasound contrast agent gas bodies (UCAGB). The primary tumor was surgically removed on day 1 after treatment. The six groups of mice were sham, LSW, sham + air bubbles, LSW + air bubbles, sham + UCAGB, and LSW + UCAGB. Data were collected for the 113 mice that survived at least 25 days. Lung evaluations were performed blind after 2 weeks of bleaching in Fekete's solution.

RESULTS

The outcomes of the three sham groups were very similar and indicated that the simple injection of material into the tumor did not increase metastasis. In comparison with the pooled shams, both the LSW + air bubbles and LSW + UCAGB groups had statistically significant increases in metastasis counts. Only the LSW + UCAGB group had a significant increase in incidence of metastasis relative to the pooled shams. The LSW + UCAGB also had significantly reduced survival.

CONCLUSION

Shockwaves can enhance metastasis from tumors, and this effect is attributable to cavitation.

Shock wave-inertial microbubble interaction: methodology, physical characterization, and bioeffect study

A method of generating in situ shock wave-inertial microbubble interaction by a modified electrohydraulic shock wave lithotripter is proposed and tested in vitro. An annular brass ellipsoidal reflector (thickness = 28 mm) that can be mounted on the aperture rim of a Dornier XL-1 lithotripter was designed and fabricated. This ring reflector shares the same foci with the XL-1 reflector, but is 15 mm short in major axis. Thus, a small portion of the spherical shock wave, generated by a spark discharge at the first focus (F1) of the reflector, is reflected and diffracted by the ring reflector, producing a weak shock wave approximately 8.5 microseconds in front of the lithotripter pulse. Based on the configuration of the ring reflector (different combinations of six identical segments), the peak negative pressure of the preceding weak shock wave at the second focus (F2) can be adjusted from -0.96 to -1.91 MPa, at an output voltage of 25 kV. The preceding shock wave induces inertial microbubbles, most of which expand to a maximum size of 100-200 microns, with a few expanding up to 400 microns before being collapsed in situ by the ensuing lithotripter pulse. Physical characterizations utilizing polyvinylidene difluoride (PVDF) membrane hydrophone, high-speed shadowgraph imaging, and passive cavitation detection have shown strong secondary shock wave emission immediately following the propagating lithotripter shock front, and microjet formation along the wave propagation direction. Using the modified reflector, injury to mouse lymphoid cells is significantly increased at high exposure (up to 50% with shock number > 100). With optimal pulse combination, the maximum efficiency of shock wave-induced membrane permeabilization can be enhanced substantially (up to 91%), achieved at a low exposure of 50 shocks. These results suggest that shock wave-inertial microbubble interaction may be used selectively to either enhance the efficiency of shock wave-mediated macromolecule delivery at low exposure or tissue destruction at high exposure.

Internal iliac arterial infusion chemotherapy for rabbit invasive bladder cancer

BACKGROUND

Internal iliac arterial infusion (IA) chemotherapy has been used clinically for locally invasive bladder cancer, but there have been no experimental studies to actually demonstrate whether IA is more effective than intravenous infusion (i.v.) chemotherapy in this setting.

METHODS

We compared the effects of IA and i.v. using a rabbit invasive bladder cancer model. A 0.2 mL suspension containing 2 x 10(6) VX2 cancer cells was inoculated into the posterior submucosa of the bladder. Two weeks later the rabbits were divided into 3 treatment groups of 8 rabbits each: controls, a group treated with IA consisting of 10 mg/kg carboplatin and 1 mg/kg pirarubicin once a week for 3 weeks (days 14, 21, and 28), and the third treated with the same regimen intravenously.

RESULTS

All bladder tumors of the rabbits in the IA group decreased in size, and 3 of the tumors totally disappeared (37.5%). There was also no evidence of lung metastasis. All tumors in the rabbits in the i.v. treatment group increased in size (tumor volume of IA vs. i.v., P = 0.008) and 2 rabbits had lung metastases. All tumors of the control group increased in size and all rabbits had lung metastases. The concentrations of platinum and pirarubicin in the bladder tumors were significantly higher in the IA treatment group than those in the i.v. treatment group at time points from 5 to 10 minutes (P < 0.05) after drug infusion.

CONCLUSION

The antitumor effect of IA may be due to higher drug concentrations in the early stage after drug delivery, and the initial circulation of high concentrations of drugs may be the most important factor in suppressing tumor growth.

The effect of high-energy shock wave therapy combined with cisplatin on mouse hepatoma

It is well documented that high-energy shock waves (HESW) can produce antitumor effects in vivo and in vitro. Furthermore, because HESW can be focused on a limited area, this therapy is considered applicable to the treatment of localized cancer. In this study, we investigated the effects of HESW therapy combined with cisplatin (CDDP) on MH134 hepatoma in a mouse model. Tumor growth was inhibited by 1 mg/kg CDDP treatment in combination with 2,000 HESW administration, but not by 1 mg/kg CDDP treatment only. Moreover, the CDDP concentration in the tumor increased after HESW administration. The active oxygen induced by HESW was then investigated by the electron spin resonance system, and it was found that HESW generated hydroxy-radicals. As oxygen radicals have been reported to change cell membrane potential, it is supposed that active oxygen induced by HESW changes cell membrane permeability, and that CDDP is concentrated in the tumor. Therefore, the combined therapy with HESW and CDDP showed synergistic inhibitory effects on tumor growth.

Enhancement of the antitumor effect by combined use of high-energy shock waves and ATX-70

The antitumor effects of high-energy shock waves (HESW) in combination with ATX-70 [a gallium-porphyrin complex, 2,4-bis(1-decyloxyethyl)-Ga(III)-1,3,5,8-tetramethylporphyrin++ +-6, 7-dipropionyl diaspartic acid [sequence: see text] were investigated. In vitro, the cell damage to mouse MH134 hepatoma after HESW treatment was enhanced by adding ATX-70. In vivo, HESW and ATX-70 combination therapy inhibited cell growth. However, neither HESW treatment alone nor ATX-70 treatment alone inhibited cell growth. These results imply that the antitumor effects of HESW and ATX-70 combined therapy are caused by activation of ATX-70 by HESW.

High-energy underwater shock wave treatment for internal iliac muscle metastasis of prostatic cancer: a first clinical trial

The first clinical trial of high-energy shock wave (SW) combined with chemotherapy to treat metastasis of prostate cancer in the internal iliac muscle was conducted. The patient, a 57-year-old man, diagnosed as having mucin-producing, poorly differentiated adenocarcinoma of the prostate invading the bladder wall, had been treated by total cystoprostatectomy. Five months later, metastatic tumors were found in the left axillar subcutaneous tissue and the right internal iliac muscles. For the axillar metastasis we performed radiation and left subclavicular arterial infusion of cisplatin 70 mg, THP-adriamycin (THP) 50 mg and methotrexate 50 mg. For the right internal muscular metastasis, 10,000 to 20,000 shots of SW and simultaneous intravenous injection of carboplatin 100 mg and THP 10 mg were carried out. Neither of the tumors decreased in size, but on magnetic resonance images, the SW-treated tumor exhibited a central low-intensity area. The SW-treated tumor was resected and central necrosis and a collection of mucin in the central area were observed. Hormone-resistant prostate cancer is well-known to be a multidrug-resistant tumor. It is noteworthy that SW and chemotherapy induced necrosis in such a refractory cancer without any significant side effects.

The combined effects of high-energy shock waves and cytostatic drugs or cytokines on human bladder cancer cells

The effects of shock waves generated by an experimental Siemens lithotripter in combination with cytostatic drugs or cytokines on several bladder cancer cell lines were examined in vitro. Proliferation after treatment was determined with the 3-4,5-dimethylthiazol-2,5 diphenyl tetrazolium bromide assay. Dose enhancement ratios were calculated for each drug and each shock wave application mode in order to characterise the sensitising effect of shock wave pretreatment. The influence of the time between shock wave and drug treatment as well as the effects of different sequences of shock wave and drug treatment or concomitant treatment were assessed for selected combinations of cell lines and drugs. It was found that shock wave treatment could render certain cell lines more susceptible to subsequent cis-platinum, mitomycin C or actinomycin D incubation. Cell lines sensitive to tumour necrosis factor alpha or interferon alpha were further sensitised to these cytokines by shock wave pretreatment. The enhanced sensitivity to cis-platinum and actinomycin D decreased rapidly during the first hours after shock wave treatment. The antiproliferative effect was most pronounced after concomitant shock wave and drug treatment. The sensitisation to interferon alpha diminishes more slowly after shock wave exposure. From the results presented in this study it is concluded that transient shock wave-induced permeabilisation of cell membrane not only enhances drug efficiency, but also causes damage to cell organelles and alterations in cellular metabolism.