Cisplatinum and interstitial laser therapy for advanced head and neck cancer: a preclinical study

The Rationale for "Laser-Induced Thermal Therapy (LITT) and Intratumoral Cisplatin" Approach for Cancer Treatment

Cisplatin is one of the most widely used anticancer drugs in the treatment of various types of solid human cancers, as well as germ cell tumors, sarcomas, and lymphomas. Strong evidence from research has demonstrated higher efficacy of a combination of cisplatin and derivatives, together with hyperthermia and light, in overcoming drug resistance and improving tumoricidal efficacy. It is well known that the antioncogenic potential of CDDP is markedly enhanced by hyperthermia compared to drug treatment alone. However, more recently, accelerators of high energy particles, such as synchrotrons, have been used to produce powerful and monochromatizable radiation to induce an Auger electron cascade in cis-platinum molecules. This is the concept that makes photoactivation of cis-platinum theoretically possible. Both heat and light increase cisplatin anticancer activity via multiple mechanisms, generating DNA lesions by interacting with purine bases in DNA followed by activation of several signal transduction pathways which finally lead to apoptosis. For the past twenty-seven years, our group has developed infrared photo-thermal activation of cisplatin for cancer treatment from bench to bedside. The future development of photoactivatable prodrugs of platinum-based agents injected intratumorally will increase selectivity, lower toxicity and increase efficacy of this important class of antitumor drugs, particularly when treating tumors accessible to laser-based fiber-optic devices, as in head and neck cancer. In this article, the mechanistic rationale of combined intratumor injections of cisplatin and laser-induced thermal therapy (CDDP-LITT) and the clinical application of such minimally invasive treatment for cancer are reviewed.

Intratumor injections of cisplatin and laser thermal therapy for palliative treatment of recurrent cancer

OBJECTIVE

The aim of this work was to report initial findings on the clinical application of intratumor injection of cisplatin in a gel (CDDP/gel) combined with laser-induced thermal therapy (LITT) for cancer treatment in a single patient with advanced stage disease.

BACKGROUND DATA

LITT with the neodymium:yttriumaluminum- garnet (Nd:YAG) laser via fiberoptics is a precise, minimally invasive alternative for thermoablation of unresectable or recurrent head and neck neoplasms, but recurrence is often seen at the treatment margins. Combining intratumor chemotherapy with interstitial laser should be most effective using drugs with thermally enhanced toxicity, such as cisplatin. The CDDP/gel therapeutic implant was expected to retain a higher concentration of cisplatin in the tumor margins for improved LITT treatment of the patient presented.

METHODS

In this case report, the cisplatin dose was 0.25 mL gel/cm(3) tumor volume (20 mg of CDDP) followed by LITT (Nd:YAG laser, 50 W, PD = 2,200 J/cm(2)) after the chemotherapy session.

RESULTS

The patient responded with local tumor eradication, and no signs of systemic toxicity were observed related to this therapy. However, the patient developed progressive metastatic disease in the lungs and died 2.5 months later.

CONCLUSIONS

This is a report of a patient with an accessible solid tumor who was treated with intratumor injection of CDDP/gel followed by LITT, which proved to be feasible. Based on preclinical evidence obtained at UCLA and the results of this study, we are encouraged to continue our refinement of LITT combined with chemotherapy for cancer treatment.

Percutaneous local ablative therapy for hepatocellular carcinoma: a review and look into the future

OBJECTIVE

To review and compare treatment result for percutaneous local ablative therapy (PLAT) with surgical resection in the treatment of small hepatocellular carcinoma (HCC).

SUMMARY BACKGROUND DATA

PLAT is indicated for small unresectable HCC localized to the liver. From the use of ethanol to the latest technology of radiofrequency ablation, ablative techniques have been refined and their role in the management of HCC established. This review aims to give an overview of various ablative methods, including their efficacy, indications, and limitations, and also tries to look into the future of clinical trials in PLAT.

METHODS

The authors reviewed recent papers in the English medical literature about the use of local ablative therapy for HCC. Focus was given to the results of treatment in terms of local control, progression-free survival, and overall survival, and to compare treatment results with those of surgery.

RESULTS

PLAT for small HCC (<5 cm) with thermal ablation (radiofrequency ablation or microwave coagulation) can achieve effective local control of disease and is superior to ethanol injection. Progressive disease in untreated areas is a common reason for failure. Overall progression-free survival is similar to that of surgical resection.

CONCLUSIONS

Thermal ablation gives good local control of small HCC, is superior to ethanol, and may be comparable to surgical resection in long-term outcome.

Percutaneous local ablative therapy for hepatocellular carcinoma: a review and look into the future

OBJECTIVE

To review and compare treatment result for percutaneous local ablative therapy (PLAT) with surgical resection in the treatment of small hepatocellular carcinoma (HCC).

SUMMARY BACKGROUND DATA

PLAT is indicated for small unresectable HCC localized to the liver. From the use of ethanol to the latest technology of radiofrequency ablation, ablative techniques have been refined and their role in the management of HCC established. This review aims to give an overview of various ablative methods, including their efficacy, indications, and limitations, and also tries to look into the future of clinical trials in PLAT.

METHODS

The authors reviewed recent papers in the English medical literature about the use of local ablative therapy for HCC. Focus was given to the results of treatment in terms of local control, progression-free survival, and overall survival, and to compare treatment results with those of surgery.

RESULTS

PLAT for small HCC (<5 cm) with thermal ablation (radiofrequency ablation or microwave coagulation) can achieve effective local control of disease and is superior to ethanol injection. Progressive disease in untreated areas is a common reason for failure. Overall progression-free survival is similar to that of surgical resection.

CONCLUSIONS

Thermal ablation gives good local control of small HCC, is superior to ethanol, and may be comparable to surgical resection in long-term outcome.

Nd:YAG laser therapy for palliation of recurrent squamous cell carcinomas in the oral cavity

BACKGROUND AND OBJECTIVES

The objective of this study was to evaluate the outcome of laser photo-thermoablation for palliation of recurrent squamous cell tumors of the oral cavity.

STUDY DESIGN/PATIENTS AND METHODS

Seventeen patients were treated with the Nd:YAG laser (power output was 50 W) delivered through a curved oral handpiece.

RESULTS

Ten patients are alive, 7 with tumor remission, and 3 with persistent disease with an average follow-up of 16 months (range = 2-36). A total of 29 tumor sites received laser treatment with 17 (58%) completely ablated. Stratified by tumor site Nd:YAG treatment led to complete local response in 8/10 buccal mucosa, 2/5 retromolar trigone, 2/2 tongue, 2/5 gingiva, 1/2 floor of mouth, 2/4 hard palate.

CONCLUSIONS

Nd:YAG laser treatment of recurrent oral cavity squamous cell carcinoma can be performed safely and repeated as needed to achieve tumor palliation. However, extended follow-up may be needed before convincing evidence of long-term therapeutic benefits is obtained.

Improved photochemotherapy of malignant cells with daunomycin and the KTP laser

Laser photochemotherapy of malignancies may become an effective palliative treatment for advanced had and neck cancer using light-sensitive, chemotherapeutic drugs activated in tumors via interstitial laser fiberoptics. Previously, it was reported that cultured human P3 squamous cells incubated 2 hours with daunomycin (Dn) exhibited tenfold enhanced cytotoxicity after exposure to argon laser light at 514 nm. This short-term uptake leads to drug localization in cytoplasmic and membrane sites prior to nuclear accumulation and daunomycin topoisomerase inhibition. In the current study phototoxicity of Dn-sensitized human cancer cells was tested using broad-spectrum white light compared to monochromatic green-wavelength light. Drug uptake and laser energy levels were optimized for maximum synergy. To test light-enhanced chemotherapy in vitro, the kinetics of cell uptake and toxicity of daunomycin was measured at 1, 2, and 5 microg/ml in three human tumor cell lines: P3 squamous-cell carcinoma, M26 melanoma, and TE671 fibrosarcoma. After 2 hr Dn uptake, all cell lines were tested for phototherapy response by exposure to 300- to 900-nm visible light from a xenon lamp or monochromatic 532-nm green light from a KTP laser. When the KTP laser output was varied from 0 to 120 Joules in Dn-sensitized tumor cells, a linear phototherapy response was seen with energy as low as 12 J inducing drug phototoxicity. These results provide evidence that daunomycin cytotoxicity is enhanced when exposed to 532-nm laser illumination in the three tumor types tested and confirm that the response is related to both energy level and drug dose.

Combined intratumor cisplatinum injection and Nd:YAG laser therapy

OBJECTIVES/HYPOTHESIS

Interstitial laser therapy (ILT) has become useful for tumor palliation in patients with advanced head and neck cancer. Cisplatinum chemotherapy also is a frequent adjuvant treatment for recurrent tumors, but systemic toxicity limits application. Intratumor cisplatinum injection combined with ILT may improve therapy of these recurrent tumors with reduced toxicity.

STUDY DESIGN

Prospective. Tumor transplants were injected with cisplatinum in a gel implant before ILT to evaluate treatment response and toxicity in a preclinical study.

METHODS

UCLA-P3 human squamous cell carcinoma tumors were grown as subcutaneous transplants in nude mice and treated by intratumor injection of 2 mg/mL cisplatinum in a slow-release, collagen-based gel carrier 4 hours before interstitial implantation of Nd:YAG laser fiberoptics to induce local tumor hyperthermia. Treatment efficacy and toxicity were followed for 12 weeks after combined drug and laser therapy compared with ILT alone.

RESULTS

Combined cisplatinum gel and ILT was a significant improvement (P < .01 by chi-square test) and induced 57% complete responses without regrowth in 21 transplanted tumors compared with only 24% in 21 tumors after ILT alone during 12-week follow-up. Recurrences in both cases appeared to result from nonuniform laser energy delivery within tumors via the implanted fiberoptic tip.

CONCLUSIONS

The results of this experimental combined cisplatinum and ILT study suggest it may be possible to improve treatment of advanced head and neck cancer by intratumor injection of gel implants containing the drug followed by interstitial Nd:YAG laser hyperthermia.

Palliative laser therapy for recurrent head and neck cancer: a Phase II clinical study

OBJECTIVES

Laser therapy is becoming a more precise, minimally invasive alternative for tumor ablation. Recent reports confirm successful palliation of pain and functional disabilities in patients with advanced deep carcinoma of the head and neck using interstitial laser phototherapy (ILT).

STUDY DESIGN, PATIENTS, AND METHODS

The current study describes an ongoing Phase II trial of neodymium/yttrium-aluminum-garnet (Nd:YAG) laser therapy for palliation of advanced head and neck cancer. A total of 40 advanced cancer patients have been entered into this protocol (25 men and 15 women).

RESULTS

Nineteen of these patients had no evidence of recurrence after ILT with an average follow-up of 11 months (range, 2 to 24 mo). Currently, 19 of these patients are alive, 14 with tumor remission and six with persistent disease. A total of 79 tumor sites received ILT with 43 (54.5%) completely ablated. Stratified by tumor site, ILT led to a complete response in 21 of 24 in the oral cavity, eight of 28 neck tumors, four of 10 in skin, and 10 of 17 in other sites. The procedure was well tolerated in most cases and was repeated at intervals in patients with residual disease or recurrences for a total of 118 laser treatments (average, 2.95 treatments per patient).

CONCLUSIONS

The results suggest that ILT can be performed safely and repeated as needed, and may be less costly than conventional surgery for head and neck cancer. However, additional follow-up is needed to obtain convincing evidence of long-term therapeutic benefits.

Laser and cisplatinum for treatment of human squamous cell carcinoma

OBJECTIVE

Interstitial laser therapy (ILT) with the neodymium:yttrium-aluminum-garnet (Nd:YAG) (1064 nm) laser via fiberoptics is becoming a more precise, minimally invasive alternative for thermoablation of unresectable or recurrent head and neck neoplasms, but recurrence is often seen at the margin. Combining intratumor chemotherapy with interstitial laser should be most effective using drugs activated by thermal energy. The objective of the current study was to test intratumor cisplatinum (cis-diaminedichloroplatinum [CDDP]) injections given in conjunction with laser therapy as an experimental approach for improved treatment of squamous cell carcinoma (SCC).

METHODS

Human SCC tumors were grown as subcutaneous transplants in nude mice and injected with CDDP (0.4 to 1.2 mg/g) in water or in collagen-based gel carrier with epinephrine (epi-gel) followed by ILT via 0.6-mm fiberoptics coupled to an Nd:YAG laser (1064 nm/180 J).

RESULTS

Tumors injected with CDDP epi-gel exhibited a partial response with two- to fourfold tumor delay compared with aqueous drug or untreated SCC transplants during 10 weeks' follow-up. Combined drug and laser therapy significantly (P < .01) decreased tumor volume, with recurrence in only 25% of animals tested compared with 78% tumor regrowth after ILT alone.

CONCLUSION

These initial results suggest that laser chemotherapy may become an effective treatment for advanced head and neck cancer.