Combined treatment of radiation and cisdiamminedichloroplatinum (II): a review of experimental and clinical data

A randomized trial of concurrent chemoradiotherapy versus radiotherapy in advanced carcinoma of the uterine cervix

The purpose of our study was to determine whether the chemoradiation is better than radiotherapy alone with respect to survival and treatment toxicity in patients with advanced carcinoma of the cervix. From October 1990 to April 1995, a total of 122 patients with advanced cervical carcinoma were included in this study and randomly assigned to either radiotherapy or concurrent chemotherapy and radiotherapy. The patients in the concurrent group received cisplatin, vincristine, and bleomycin every 3 weeks for a total of four courses, in combination with radiotherapy concurrently. Sixty patients were randomized to the concurrent chemoradiotherapy, and 62 were randomized to the radiotherapy alone. A tumor response was observed in 88.3% of the patients in concurrent group and in 74.2% of the patients in radiotherapy group (P = 0.04). After a median follow-up of 46.8 months, the overall disease-free survival and actuarial survival rate at 3 years were 51.7 and 61.7% in the concurrent group, and 53.2 and 64.5% in the radiotherapy group, respectively. Treatment-related toxicity appears to be higher with the combination of radiotherapy and chemotherapy compared with radiotherapy alone (36.7% versus 17.7%, P = 0.02). However, analysis by Kaplan-Meier method showed that the actuarial survival was not statistically different between the chemoradiotherapy and radiotherapy groups (mean survival time: 38.1 months versus 41.5 months, P = 0.27). In conclusion, this study showed that concurrent multiagent chemoradiotherapy did not prove to be a superior definitive therapy over radiotherapy alone for patients with advanced cervical carcinoma.

Addition of cisplatin improves efficacy of 131I-labeled monoclonal antibody 323/A3 in experimental human ovarian cancer

This study was conducted to determine whether the cytotoxic agent cisplatin (CDDP), also known as a radiosensitizer, can improve the efficacy of the 131I-labeled monoclonal antibody (MAb) 323/A3 in the treatment of experimental human ovarian cancer.

METHODS AND MATERIALS

Nude mice bearing well-established subcutaneous FMa, OVCAR-3, or Ov.Pe xenografts were injected twice with a 2-week interval either with a bolus of CDDP, 131I-323/A3, or with a combination of both modalities. CDDP was injected at various timepoints when combined with 131I-323/A3. The efficacy of the treatment was expressed as the specific growth delay (SGD). The growth inhibitory effect of the combination was characterized to detect additivity or synergism, using the mean relative tumor volumes at 2, 4, and 6 weeks after the last injection as endpoints.

RESULTS

The efficacy of 131I-323/A3 was superior to that of the maximum tolerated dose (MTD) of CDDP (6 mg/kg) in all three xenografts. The addition of CDDP to 131I-323/A3 could increase the growth inhibition in the CDDP-responsive FMa and OVCAR-3 xenografts, but not in Ov.Pe xenografts. Although this improved antitumor effect was additive rather than synergistic, the combination was more effective when compared with that of the MTD of each of the modalities alone. The time interval between the administration of a bolus injection of CDDP and 131I-323/A3 had no effect on the extent of growth inhibition in OVCAR-3 xenografts.

CONCLUSION

The addition of CDDP to 131I-323/A3 resulted in an additive inhibitory effect on the growth of CDDP-responsive xenografts. As the combination of radioimmunotherapy and CDDP was more effective in the inhibition of the tumor growth when compared with that of the MTD of each of the modalities alone, this treatment may therefore be considered of use in patients with ovarian cancer responsive to CDDP.

Radiotherapy with concomitant continuous cisplatin infusion for unresectable tumors of the upper aerodigestive tract: results of a phase I study

A phase I-II study was initiated in February 1991 of concomitant radiation and cisplatin (CDDP) in the treatment of unresectable head and neck squamous cell carcinomas (n = 12). The first patient was treated palliatively for a cervical recurrence of laryngeal cancer. The 11 other patients had locally advanced (stage IV) previously untreated carcinomas of the oropharynx (n = 9), hypopharynx (n = 1), or cervical node with unknown primary site (n = 1). Standard external radiation was carried out up to a total dose of 60 Gy/6 weeks (7 MeV electron beam) for the first patient and 72 Gy/8 weeks (Co60 beam) for the other 11 patients. CDDP was infused continuously during the entire radiation treatment, 5 days/week. The starting dose was 4 mg/m2/day and was escalated by increments of 1 mg/m2/day; dose-limiting toxicity was observed at 7 mg/m2/day. Neutropenia (grade 4, one patient; grade 3, three patients) and thrombocytopenia (grade 3, one patient; grade 2, one patient) were the limiting factors. Therefore, the recommended dose of CDDP is 6 mg/m2/day. All patients but one completed the scheduled radiation. For the entire group, mucositis was not more severe than that observed with radiotherapy alone. There was no nephro-, oto-, or neurotoxicity. A complete response was obtained in eight (66%) patients. Of these, four were free of disease 12-34 months after completion of treatment and one had a total glossectomy for a tongue necrosis. For the whole series, the mean overall survival was 16 months posttreatment. Pharmacokinetic analysis indicated the total cisplatin accumulation at the end of treatment to be 743-1551 ng/ml. Accumulation of ultrafilterable platin was noted in only one patient (137 ng/ml at the end of treatment).

The effect of cisplatin pretreatment on the accumulation of MIBG by neuroblastoma cells in vitro

[131I]meta-iodobenzylguanidine ([131I]MIBG) provides a means of selectively delivering radiation to neuroblastoma cells and is a promising addition to the range of agents used to treat neuroblastoma. As MIBG is now being incorporated into multimodal approaches to therapy, important questions arise about the appropriate scheduling and sequencing of the various agents employed. As the ability of neuroblastoma cells to actively accumulate MIBG is crucial to the success of this therapy, the effect of chemotherapeutic agents on this uptake capacity needs to be investigated. We report here our initial findings on the effect of cisplatin pretreatment on the neuroblastoma cell line SK-N-BE (2c). After treating these cells with therapeutically relevant concentrations of cisplatin (2 microM and 20 microM), a stimulation in uptake of [131I]MIBG was observed. Reverse transcription-polymerase chain reaction (RT-PCR) analysis demonstrated that this effect was due to increased expression of the noradrenaline transporter. These results suggest that appropriate scheduling of cisplatin and [131I]MIBG may lead to an increase in tumour uptake of this radiopharmaceutical with consequent increases in radiation dose to the tumour.

Optimal use of the 131-I-metaiodobenzylguanidine and cisplatin combination in advanced neuroblastoma

Neuroblastoma (NB), a childhood radiosensitive tumor, is very aggressive and malignant, in its disseminated form, despite very intensive chemotherapy, prognosis continues to be dismal. Owing to its capacity to concentrate in NB lesions, large doses of 131-I-MIBG, have given very encouraging therapeutic results in patients resistant to conventional therapy as well as at diagnosis. We recently reported the first attempt in combination therapy (CO-TH) using 131-I-MIBG and cisplatin. This new form of CO-TH appears very effective in obtaining a rapid and excellent response in relapsed patients. In this report, we describe the results of further experience with CO-TH in disseminated NB. We have attempted to verify to what extent interaction between the effects of the two agents may produce therapeutic benefit, and we have sought the optimization of CO-TH use. Three stage IV NB patients were treated with CO-TH. The following treatment schedule, was planned: day 1, cisplatin 50 mg/m3 i.v. over 6 h; day 2, 131-I-MIBG 100-130 mCi at high specific activity (-1.1 Gbq/mg) i.v. over 6 h followed, a week later, by the same treatment combination. The therapeutic results were encouraging. However, hematological toxicity continued to represent a major limiting factor. In view of the overall effectiveness of CO-TH, at the price of lasting hematological toxicity, it may be indicated as a consolidation regimen some time before conditioning chemotherapy for autologous bone marrow transplantation.

[Concomitant radiochemotherapy for locally advanced bronchial cancers: current results and prospects]

The prognosis of locally advanced lung cancer is reportedly poor in all histologic types. In non-small cell lung cancer, radiation therapy alone results in disappointing long-term survival. Three recent randomized trials, however, have shown a limited but significant improvement of survival with induction chemotherapy, though local control remained poor in these studies as well as in small-cell lung cancer treated with chemotherapy and late radiotherapy. Two randomized trials focusing on small-cell lung cancer have recently shown significant benefit due to the combination of early concurrent mediastinal irradiation and chemotherapy, with major improvement in local control and a more than 40% 2-year survival rate. The concept of concurrent chemoradiotherapy has also been studied in non-small cell carcinoma with several pilot studies leading to both encouraging results and improved survival rate (up to 40% at 2 years). Ongoing phase III trials are comparing sequential versus concurrent chemoradiotherapy and will define the role of radical surgery after chemoradiotherapy in locally advanced non-small cell lung cancer.

Combined postoperative radiotherapy and weekly cisplatin infusion for locally advanced head and neck carcinoma: final report of a randomized trial

PURPOSE

To report the final results of a prospective randomized trial that aimed to evaluate efficacy and toxicity of concomitant postoperative radiotherapy and Cisplatin infusion in patients with Stage III or IV squamous cell carcinoma of the head and neck and histological evidence of extracapsular spread of tumor in lymph node metastase(s).

METHODS AND MATERIALS

Radiotherapy was delivered using a daily dose of 1.7 Gy for the first 54 Gy and 1.8 to 2 Gy until the completion of the treatment. Cisplatin 50 mg i.v. with forced hydratation was given or not every week (i.e., seven to nine cycles) concurrently with radiotherapy. A total of 44 patients were treated by irradiation only (RT group) and 39 by irradiation with chemotherapy (CM group).

RESULTS

The RT group displayed a higher rate of loco-regional failures as compared to CM group (41 vs. 23%; p = 0.08). The overall survival, the survival corrected for deaths by intercurrent disease, and the disease-free survival were better in CM group as compared to RT group with statistically significant differences. Survival without loco-regional treatment failure was better in the CM group, the difference being close to the level of significance (p = 0.05). Survival without distant metastases were comparable in the two therapeutic groups. Ten severe late complications were observed, four in the RT group (17%) and six in the CM group (22%). Cox univariate analysis confirmed the importance of the therapeutic modality in predicting the overall survival, the survival corrected for deaths by intercurrent disease, and the disease-free survival.

CONCLUSIONS

The present final report of this phase III study confirms preliminary results. The concomitant use of 50 mg weekly Cisplatin infusion and postoperative radiation improved loco-regional control and survival. No significant increase of late radiation complications was observed in the CM group.

An interaction of cisplatin and radiation in two rat yolk sac tumour cell lines with different radiosensitivities in vitro

We investigated the interaction of cisplatin and radiation in two rat yolk sac tumour cell lines with different radiosensitivities in vitro. The effects were assessed by clonogenic assay. D0 for the radiosensitivity of the radioresistant variant cell line, NMT-1R was 139 cGy, which was 1.3 times larger than that for the parent radiosensitive cell line, NMT-1 (D0 = 107 cGy). The concentration of cisplatin required to reduce colony formation by 50% at 1 h treatment (ID50 of cisplatin) was 0.25 microgram/ml for NMT-1, whereas that for NMT-1R was 1.0 microgram/ml. Cisplatin potentiation of radiation sensitivity was manifested by the decrease in the slope of the radiation dose-response curve. D0's for NMT-1 and NMT-1R were 83 and 100 cGy in combined treatment with ID50 of cisplatin immediately before radiation. The enhancement ratios of cisplatin were therefore 1.30 for NMT-1 and 1.39 for NMT-1R respectively in D0. No different enhancement ratio for cisplatin was observed in the time course of combination treatment with cisplatin and radiation within the interval of 6 h. There was no clear change in cell cycle distribution within 6 h after treatment with ID50 of cisplatin for both cell lines. In conclusion, cisplatin had a synergistic effect on both cell lines which was independent of the time course and sequence in combination with radiation within 6 h.

Cisplatin, hyperthermia and radiation treatment in human cisplatin-sensitive and resistant glioma cell lines

In this study, the effects of mild protracted hyperthermia, combined with prolonged exposure to cisplatin and low dose-rate irradiation (LDRI), were examined in two human cell lines. The cell lines are human glioma parental and cisplatin-resistant variant cells. The results show that mild hyperthermia at 40 degrees C was able to sensitize both the parental and the variant cisplatin-resistant cells to cisplatin treatments (1 microgram/ml for up to 20 h) when the two treatments were given concurrently. When mild hyperthermia and cisplatin were given with LDRI concurrently, additional enhanced cell killing was observed in both the parental and the cisplatin-resistant variant cells. Further analysis of the results showed that when the effects of the trimodality treatment were normalized to the effects of the combined treatment of mild hyperthermia with cisplatin, the residual cell killing was still greater than that observed for radiation alone, indicating a synergistic interaction. This synergistic interaction was greater for the parental line compared to the cisplatin-resistant line. Thus, these data show that the concurrent application of mild hyperthermia, low concentration, long duration, cisplatin and low-dose rate irradiation may be an effective form of treatment in both normally responding and cisplatin-resistant variant human tumour cell lines.

Paclitaxel-induced radiation recall dermatitis

The authors present a case of radiation recall dermatitis occurring in a patient receiving paclitaxel shortly after completion of radiation therapy. A brief review of previously reported taxane-induced radiation recall reactions is provided.

Cisplatin and low dose rate irradiation in cisplatin resistant and sensitive human glioma cells

PURPOSE

Human glioma cell lines resistant (U373MGCP) and sensitive (U373MG) to cisplatin were used to evaluate the effect of cisplatin as a sensitizer to low dose rate irradiation (LDRI).

METHODS AND MATERIALS

A cisplatin resistant glioma cell line U373MGCP was developed by chronic exposure of parental U373MG cells to cisplatin. Plateau phase cells were treated with cisplatin, high dose rate (HDR) irradiation (1.12 Gy/min), LDRI (0.0088 Gy/min), or cisplatin concurrent with LDRI. Cell survival was determined by the colony forming assay.

RESULTS

Both cell lines showed increased resistance to radiation at LDR compared with HDR, with Dose Modifying Factors (DMF at 10% survival level) of 1.7 for U373MG and 2.5 for U373MGCP. The increased LDR sparing effect in the cisplatin resistant U373MGCP cells indicates increased repair proficiency. The resistant cell line showed a fourfold increase in resistance to cisplatin cytotoxicity at the 10% survival level compared with the parental U373MG cells. Cisplatin enhanced the response of both cell lines to LDRI. The DMFs were 1.2, 1.2, and 1.7, respectively, for the sensitive U373MG cell line given 1 microgram/ml, and the resistant cell line given 3 or 6 micrograms/ml cisplatin treatments concurrent with LDRI.

CONCLUSIONS

These data show that cisplatin can be an effective sensitizer to LDRI in both cisplatin resistant and sensitive glioma cell lines. However, in the resistant cell line, higher concentrations of cisplatin were necessary to achieve the same level of sensitization as in the sensitive cell line.

Feasibility of escalating daily doses of cisplatin in combination with accelerated radiotherapy in non-small cell lung cancer

The aim of this study was to determine whether it is feasible to reduce the overall treatment time from 7 to 4 weeks in patients with non-small cell lung cancer (NSCLC) receiving radiotherapy with cisplatin. This follows an EORTC phase III randomised trial (08844) in which cisplatin given before each radiation dose resulted in improved local control and survival, but which had a relatively long treatment period of 7 weeks [Schaake-Koning et al., N Engl J Med 1992, 326, 524-530]. 38 patients with confirmed NSCLC (2 stage I, 1 stage II, 18 stage IIIA, 17 stage IIIB) received a total tumour dose of 55 Gy/20 fractions/26 days, from January 1992 to March 1994. Daily fractions of 2 Gy (5 times/week) were given to the macroscopic tumour and the non-involved adjacent lymph node areas. During the same session, a dose of 0.75 Gy was given to the macroscopic tumour (simultaneous boost). Cisplatin 6 mg/m2 was administered 1-2 h before each fraction, in an escalating total dose, during week 1 in 3 patients, during weeks 1 and 2 in 6 patients, during weeks 1, 2 and 3 in 5 patients and during the whole treatment in 24 patients. 38 patients were evaluable for acute side-effects (WHO). Maximal therapy-related toxicity (WHO) was grade 3 (nausea/vomiting in 2 patients, oesophagitis in 3 patients, dyspnoea in 3 patients, cough in 1 patient). Late side-effects were evaluated in 34 patients. There was grade 2 oesophagitis in 2 patients; grade 3 toxicity in 8 patients (tiredness in 3 patients, dyspnoea in 3 patients, oesophagitis in 2 patients); grade 4 toxicity in 4 patients (dyspnoea in 3 patients, cough in 1 patient). Pulmonary fibrosis grade 3 occurred in 4 and grade 4 in 6 patients. One patient developed a severe (grade 3) radiation pneumonitis. The low incidence of acute and late side-effects with this treatment, combining daily administration of 6 mg cisplatin with radical radiotherapy using a simultaneous boost technique, indicates that escalation of the radiation dose seems feasible.

Concurrent cisplatin, etoposide, and radiotherapy for unresectable stage III nonsmall cell lung cancer: a phase II study

PURPOSE

Prognosis of unresectable Stage III nonsmall cell lung cancer (NSCLC) treated with thoracic radiotherapy alone has been disappointing. In recent years, several Phase III trials have demonstrated encouraging results with induction chemotherapy, but with poor long-term local control. Concurrent cisplatin alone during the radiation therapy course has resulted in improved local control, but without efficacy on occult metastatic disease. Intensification of chemotherapy during radiation has the potential of improving both local control and metastasis-free survival. This Phase II study was undertaken to determine the feasibility, toxicity, response rate, local control, and survival of concurrent chemotherapy with cisplatin-etoposide and radiotherapy in unresectable Stage IIIA and IIIB nonsmall cell lung cancer.

METHODS AND MATERIALS

Between February 1992 and April 1993, 50 patients with either medically or technically inoperable Stage III NSCLC were treated with concurrent chemoradiotherapy. Thoracic radiotherapy was administered to a total dose of 60 Gy. Concurrent chemotherapy consisted of cisplatin 20 mg/m2/day plus etoposide 50 mg/m2/day, from day 1 through day 5, every 4 weeks for four cycles. Medically operable patients were evaluated for surgical resection after 45 Gy and two cycles of concurrent chemotherapy. All patients received an esophagitis preventive regimen.

RESULTS

Response rate was 84%, including 68% complete response. With a minimum follow-up of 23 months, overall survival was 70% at 1 year, 39.7% at 2 years, and 34.7% at 3 years. Median survival was 18 months. Age, performance status, histologic type and grade, and stage and tumor size, did not influence survival, with the exception of contralateral nodal involvement (p = 0.0055). Patients achieving a complete response (n = 34) had a 2-year survival of 58.4% compared to 0% for nonresponders (p < 0.0001). Patients who could benefit from surgery (n = 9) had a 2-year survival of 77.8% compared to 31.2% for nonoperated patients (p < 0.013). Seventeen patients (34%) are currently alive and free of disease. Actuarial local control was 63.4% at 1 year, and 58.5% at 2 and 3 years, respectively. Major hematologic toxicity occurred in 24% of the patients.

CONCLUSIONS

Concomitant chemoradiotherapy with cisplatin and etoposide at this dose level is a well tolerated outpatient regimen, which resulted in a high local control rate, and an encouraging survival at 1, 2, and 3 years. A direct comparison of this treatment schedule to induction chemotherapy followed by radiotherapy, or concurrent chemoradiation therapy using cisplatin alone, appears warranted.

Concomitant low dose-rate irradiation and cisplatin treatment in ovarian carcinoma cell lines sensitive and resistant to cisplatin treatment

Human ovarian carcinoma parental and cisplatin-resistant cells were evaluated for their radiation sensitivity to high and low dose-rate irradiation and for the effectiveness of cisplatin in radiosensitization. The cisplatin resistant variant A2780cp showed increased radiation resistance for both low dose-rate (LDRI) and high dose-rate irradiation. For cisplatin treatment for 1 h before and after HDRI there was radiosensitization in only the cisplatin-resistant variant. Concomitant cisplatin treatment during LDRI resulted in radiosensitization in both cell lines with dose-modifying factors ranging from 1.6 to 5.8. In this case greater radiosensitization was achieved in the parental cell line. In both cell lines the dose-modifying factors were larger when the cisplatin was refreshed every 6 h instead of 12 h during LDRI. These data show that cisplatin may be a very effective radiosensitizer when given during LDRI which is used in brachytherapy.

Radiosensitizing effect of cisplatin in prostate cancer cell lines

The radiosensitizing effect of platinum compounds has been demonstrated in a number of tumors. In prostate cancer, clinical and preclinical data concerning an eventual efficacy of the concept of radiosensitization are lacking. In the present study cisplatin and carboplatin have been used as a model to explore radiosensitization in in vitro prostate cancer cell lines. Human (DU-145) and rat (R3327-MATLyLu) prostate tumor cells were irradiated with doses ranging from 0 to 8 Gy in the presence of various concentrations of either cisplatin or carboplatin. For the evaluation of the combined effect of the two treatment modalities, a simple model is presented. Supra-additive treatment effects of combinations of platinum drugs with radiotherapy, both at clinically achievable doses, were shown on the basis of surviving fractions of tumor cells and proved to be significant. These data strongly suggest that radiotherapy may be effectively combined with radiosensitizers such as platinum drugs in prostate cancer therapy, to yield synergism in treatment efficacy.

Effect of cisplatin on the clinically relevant radiosensitivity of human cervical carcinoma cell lines

PURPOSE

To evaluate the effect of clinically relevant levels of cisplatin on the radiosensitivity of human cervical tumor cells, and to estimate what changes in local control rates might be expected to accrue from the concomitant use of cisplatin during fractionated radiotherapy.

METHODS AND MATERIALS

The effects of concomitant cisplatin (1 microgram/ml, a typical intratumor concentration) on the clinically relevant radiosensitivity, i.e., surviving fraction after 2 G (SF2) values, was determined in 19 cloned human cervical tumor cell lines. These early passage cell lines had SF2 values ranging from 0.26 to 0.87.

RESULTS

The concomitant administration of cisplatin reduced the clinically relevant radiosensitivity in the majority (11 out of 19) of the human tumor cell lines investigated. In only 4 out of 19 was any radiosensitization observed, and in 4 out of 19 cell lines there was no significant change in radiosensitivity. However, the sum of the independent cell killing by radiation and cisplatin, was approximately twofold higher than after radiation alone. There was no apparent dependence of the cisplatin-induced changes in SF2 values upon the level of cell killing by cisplatin. However, there is a suggestion that concomitant cisplatin administration may have a differential effect in inherently radiosensitive and resistant human tumor cell lines.

CONCLUSIONS

Our data suggest that concomitant cisplatin/radiotherapy regimens may result in a higher level of local tumor control, but primarily through additive toxicity and not through radiosensitization. Future improvements in local tumor control may, thus, be derived by increasing the total dose of cisplatin.

Carboplatin- and cisplatin-induced potentiation of moderate-dose radiation cytotoxicity in human lung cancer cell lines

The interaction between moderate-dose radiation and cisplatin or carboplatin was studied in a cisplatin-sensitive (GLC4) and -resistant (GLC4-CDDP) human small-cell lung cancer cell line. Cellular toxicity was analysed under oxic conditions with the microculture tetrazolium assay. For the platinum and radiation toxicity with the clinically relevant dose ranges applied, this assay was used to obtain information on cell survival after the treatments. Apart from effects on cell survival effects on DNA were also investigated. Configurational DNA changes could be induced by platinum drugs and thereby these drugs might change the frequency of DNA double-strand breaks (dsbs). DNA fragmentation assayed with the clamped homogeneous electric field (CHEF) technique was used as a measure for dsbs in DNA. The radiosensitising effect of the platinum drugs was expressed as enhancement ratio (ER) calculated directly from survival levels of the initial slope of the curve. The highest ER for cisplatin in GLC4 was 1.39 and in GLC4-CDDP 1.38. These were all at 75% cell survival. Carboplatin showed increased enhancement with prolonged incubation up to 1.21 in GLC4 and was equally effective as cisplatin in GLC4-CDDP. According to isobologram analysis, prolonged incubation with both platinum drugs showed at least additivity with radiation for both cell lines at clinically achievable doses. GLC4-CDDP showed cross-resistance to radiation. The radiosensitising capacity of both lung cancer cell lines was not dependent on their platinum sensitivity. The formation of dsbs in DNA directly after radiation was not influenced by pretreatment of either drug in the sensitive or in the resistant cell line. Drug treatment resulted in decreased DNA extractability in control as well as in irradiated cells. Modest enhancement ratio for radiosensitisation by platinum drugs cannot be explained on the level of dsb formation in DNA in both cell lines. Interaction of radiation with the clinically less toxic carboplatin can be improved by prolonged low-dose carboplatin exposure before irradiation and is as potent as cisplatin in the resistant lung cancer cell line. This suggests an advantage in combining radiation and carboplatin in lung cancer patients.

Split hyperfractionated accelerated radiation therapy and concomitant cisplatin for locally advanced head and neck carcinomas: a preliminary report

PURPOSE

The feasibility and activity of an intensive chemoradiotherapeutic scheme for patients with locally advanced squamous cell head and neck cancers were tested in a single institution Phase II pilot study.

METHODS AND MATERIALS

Between January 1990 and February 1992, 40 patients were entered into this trial. The treatment protocol consisted of split hyperfractionated accelerated radiation therapy (SHART), 1.6 Gy per fraction given twice per day to a total dose of 64-67.2 Gy for a total of 6 weeks with a 2-week gap, and cisplatin (20 mg/sqm/Days 1 to 5, in continuous perfusion) concomitantly.

RESULTS

All of the 40 patients are evaluable for response and survival. Toxicity was significant, but tolerable. A complete tumor response to this treatment was achieved by 37 patients (92.5%). With a minimal follow-up of 22 months (median 30 months) there have been 16 local relapses and 19 patients have died, 2 without tumor. The projected 2- and 3-year overall survival rates are 64% (confidence interval (CI) 95%, 49-79%) and 47%, respectively. The 2-year local control probability has been 56% (CI 95%, 39-73%).

CONCLUSION

This treatment obtains a high rate of complete responses with increased acute toxicity but tolerable late effects. Preliminary results are encouraging for laryngeal neoplasms. A longer follow-up is needed to evaluate the impact of this treatment on patient survival.

Chemoradiation in advanced nonsmall cell lung cancer

PURPOSE

Resectability, local control, and survival were evaluated in advanced stage nonsmall cell lung cancer treated with simultaneous chemoradiation therapy delivered in an accelerated, interrupted twice-a-day schedule.

METHODS AND MATERIALS

Forty-seven consecutive patients with Stage IIIA or IIIB nonsmall cell lung cancer, consenting to participation in the study, received cisplatin, 30 mg/m2 for 3 days, etoposid, 80 mg/m2 for 3 days, and 5-fluorouracil, 900 mg/m2 for 4 days. Radiation therapy consisted of 2 Gy given twice a day for 5 days. Two weeks rest was planned between cycles. Patients were evaluated for resectability after the second cycle. Any patient with unresectable tumor received a third cycle of treatment.

RESULTS

Forty-seven patients were evaluable for acute toxicity: eighteen (38%) required an extended rest period for esophagitis or low blood count; 3 (6%) had sepsis, of whom 1 (2%) expired. Three patients (6%) had multiple blood transfusions for low hemoglobin. Median follow-up is 23.6 months, with a range of 10-49 months. Nine patients (19%) failed locally; 15 (32%) had local and distant failure; 7 (15%) failed only at distant sites. Twelve patients (25.5%) are alive with no evidence of disease; 4 patients were lost to follow-up with disease. The 2-year actuarial survival is 49%, and the 4-year is 28.2%.

CONCLUSION

Simultaneous chemoradiation is well tolerated with acceptable toxicity. The overall 2- and 4-year actuarial survival is somewhat better than that reported in the literature. Resectability in Stage IIIB patients was not increased with this regimen nor was any surgical specimen free of cancer. The 47% distant failure rate is not different from those reported by others.

Combined modality treatment for stage III non-small cell lung cancer

There are increasing reports of studies in which combined modality treatment is being tested in stage III non-small cell lung cancer. Randomized trials in which sequential chemoradiotherapy has been compared to radiation alone and in which single agent cisplatin and simultaneous thoracic radiation were compared to radiation are reviewed and discussed. The largest and the most mature phase II trials of preoperative chemotherapy are also included in this review. Similarly the results from recently reported small randomized trials evaluating preoperative treatment are described. Potential future directions for clinical trials are suggested, including the incorporation of new agents in combined modality regimens.

Simultaneous radiochemotherapy in the treatment of inoperable, locally advanced head and neck cancers. A single-institution study

BACKGROUND

Patients with advanced, inoperable head and neck cancers have cure rates of approximately 10-15%. In these patients, concomitant chemoradiotherapy seems to improve local control and survival. 5-Fluorouracil (5-FU) administered by continuous infusion and cisplatin plus concomitant conventional radiation therapy may be promising in treating advanced, inoperable head and neck cancers.

METHODS

Forty-five evaluable patients with primary nonmetastatic, inoperable head and neck cancers were treated. From January 1987 to April 1988, the patients were treated with cisplatin plus radiation therapy (Group 1) and from May 1988 to November 1990, they were treated with the same combination plus 5-FU, given in continuous infusion (Group 2). Clinical and pathologic responses were assessed after radiation therapy was completed. Patients who relapsed underwent salvage surgery, if possible. The disease free and overall survival rates of the patients were evaluated.

RESULTS

The overall response rate (complete and partial response) was 93%, 60% of which comprised complete remissions. Despite the high response rates obtained in the two groups, the time to progression for complete responses and the median survival time were unsatisfactory (13 [Group 1] and 10 months [Group 2] and 17 [Group 1] and 16 months [Group 2], respectively). The toxicity rate from the two treatments was not relevant. A Grade II mucositis, according to the World Health Organization, was found in 25 patients, and the treatment was interrupted for 7-10 days in 5.

CONCLUSIONS

In this study, despite an improvement in the number of complete responses, the chemotherapeutic regimen with or without 5-FU did not prolong the overall patient survival significantly.

Simultaneous cisplatin and radiation in endometrial adenocarcinoma cell lines

The effects of concomitantly administered cisplatin and radiation were evaluated in four recently established endometrial adenocarcinoma cell lines. We used the 96-well clonogenic assay to obtain survival data which were fitted to the linear quadratic model. The area under the survival curve (AUC) was obtained by numerical integration. It turned out that there was only a systematic additive cytotoxic effect and no supra-additive, true radiosensitising effect could be found. The results were not affected by the cisplatin dose used, the intrinsic radiosensitivity of the cell lines or the sensitivity of the cells to cisplatin.

A new approach in the treatment of stage IV neuroblastoma using a combination of [131I]meta-iodobenzylguanidine (MIBG) and cisplatin

The outlook for disseminated neuroblastoma (NB) continues to be dismal. NB is a radiosensitive tumour. Owing to its high concentration in NB lesions, [131I]meta-iodobenzylguanidine [131I]MIBG has the potential for specifically delivering very large radiation doses to the malignant cells. Encouraging results have been reported with [131I]MIBG used alone in patients resistant to conventional therapy and at diagnosis. We report the first attempt to explore the integration of this new treatment modality with chemotherapy. Among the drugs effective in NB, cisplatin was chosen because of its high degree of activity against NB, its mild haematological toxicity and the known synergism between cisplatin and radiation. 4 patients, 3 with relapsed, heavily pre-treated, progressive stage IV NB, and 1 with stage IV NB at diagnosis, all with a good [131I]MIBG uptake, were investigated with combined therapy (CO-TH). Two complete remissions and one partial remission were observed in these patients 4-6 weeks following only a single course of both cisplatin and [131I]MIBG at "standard" dosage. The only toxicity was haematological, which was significant and relatively long-lasting, but was not associated with any serious infections or bleeding tendency. The general condition of these patients during the entire study period was excellent. The fourth patient, investigated at diagnosis with a modified less intensive treatment, obtained a partial remission with mild haematological toxicity. During the subsequent courses of intensive multidrug chemotherapy, this patient showed haematological toxicity comparable with that experienced by patients treated with an identical drug combination, but without previous treatment with CO-TH. The provisional conclusion of this ongoing study is that this new form of CO-TH appears most effective in obtaining a rapid and excellent response in heavily pretreated relapsed patients with progressive disease, and should be further investigated in earlier stages of the disease.

Head and neck cancer: present status and future prospects of adjuvant chemotherapy

For more than 15 years, active clinical research and continuing efforts in the field of CT in head and neck cancer have produced a modest but definite progress and achievements in this disease. We are a long way away from producing more definitive and acceptable results and higher cure rates in this disease. The achievements of systemic CT in patients with head and neck cancers are summarized in this review. Continuing efforts and investigation are needed to study the efficacy of systemic CT in patients with resectable head and neck cancer. We are continuing to investigate the best timing and sequence of CT as part of CMT and then the efficacy of such treatment in patients with resectable cancer. Efforts are underway to improve on the results in patients with NPC and patients with unresectable disease with the use of chemotherapy as part of CMT. Efforts are also underway to consolidate and improve on the results obtained with systemic CT to preserve laryngeal function. We strongly believe that with continuation of these serious efforts further achievement and impact can be obtained with systemic CT as part of other modalities in these patients.

Expression of epidermal growth factor receptor and proliferating cell nuclear antigen predicts response of esophageal squamous cell carcinoma to chemoradiotherapy

BACKGROUND

Multimodality therapy with chemotherapy and radiotherapy followed by surgery may improve survival in patients with esophageal squamous cell carcinoma compared with each of the individual treatment options. Histologic assessment of resected tumors after chemoradiotherapy shows that some patients have a complete response with no residual tumor, whereas other patients derive no benefit. The ability to predict response to chemoradiotherapy would allow treatment to be planned accordingly.

METHODS

Expression of the tumor growth and proliferation proteins epidermal growth factor receptor (EGFR) and proliferating cell nuclear antigen (PCNA) was determined using immunohistochemical staining of pretreatment endoscopic biopsies from patients with esophageal squamous cell carcinoma who were randomized to chemoradiotherapy before surgery. Response to chemoradiotherapy was assessed by histologic examination of the resected specimens. Response to chemoradiotherapy and survival were correlated with EGFR and PCNA expression individually and with both markers combined as EGFR/PCNA:

RESULTS

Of 14 patients available for study, 6 had a complete histologic response (CR) to chemoradiotherapy with no residual tumor in the resected specimen, 3 had a partial response (PR) to chemoradiotherapy, and the remaining 5 had minimal response (MR). Of the nine patients with a CR or PR, tumors of eight patients were negative for one or both markers. Of the five patients with an MR, four tumors were positive for both EGFR and PCNA (P < 0.05, Fisher's exact test). Comparison of survival from the date of randomization shows that patients with tumors negative for one or both markers had a significant survival advantage (P = 0.0003, log-rank test).

CONCLUSIONS

Evaluation of PCNA and EGFR status of pretreatment biopsies may identify a group of patients likely to derive the greatest benefit from chemoradiotherapy before surgery in terms of histologic response and long term survival.

Concurrent irradiation and intratumoral chemotherapy with cisplatin: a pilot study in dogs with spontaneous tumors

PURPOSE

A preliminary study was undertaken to determine whether the addition of a collagen gel in the formulation of cisplatin for intratumoral administration of cisplatin affected platinum plasma concentrations. A second study was undertaken to determine the local effects of intratumoral administration of cisplatin mixed with collagen given concurrently with irradiation.

METHODS AND MATERIALS

Twelve dogs with advanced stage tumors were administered a dose of 0.25 mg of cisplatin per kg of body weight intratumorally with or without collagen using a two-period crossover design. Twelve additional dogs received concurrent irradiation (48 Gy) delivered in 12 fractions over 4 weeks and intratumoral cisplatin chemotherapy given the first day of each week at a dose of 0.5 mg of cisplatin per cm3 of tissue.

RESULTS

The cumulative cisplatin plasma concentrations varied over time from dog to dog, but the use of collagen in the formulation significantly reduced the systemic exposure of cisplatin. For the dogs given intratumoral cisplatin and irradiation, complete responses were observed in 10 dogs. Seven dogs had local recurrence. One dog had tumor recurrence in the radiochemotherapy field and six dogs had recurrence at the margin of the radiochemotherapy field, but within the irradiation field. Normal tissue reactions were similar in the radiochemotherapy field and in the margin treated with radiation only. Cumulative effect of repeated intratumoral administration on plasma concentration of cisplatin was not observed.

CONCLUSIONS

These findings provide support for an extended investigation of this combined regimen. The lack of systemic toxicity associated with intratumoral administration of cisplatin mixed with collagen may allow a safe clinical evaluation of the interaction between cisplatin and radiation.

Role of radiotherapy in the treatment of cancer of the ovary

The initial management of carcinoma of the ovary is surgical. The need for further treatment is determined by a consideration of tumor stage, grade, and the presence of residual disease. Approximately one-third of patients are suitably managed by primary post-operative radiotherapy directed to the entire abdomen and pelvis with curative intent. Patients are mainly derived from stages I and II. Stage III patients are also included if the tumor is of low grade and there is no pelvic residuum. The dose which can be safely delivered to the upper abdomen is limited by normal tissue tolerance. Curative radiation is inappropriate for patients with upper abdominal disease and/or more than small volume residuum in the pelvis. These patients are best managed with chemotherapy. Suitably selected patients have a ten-year relapse-free survival of 68% following radiotherapy. Acute gastrointestinal symptoms are common during the treatment, but are usually amenable to symptomatic management. Long term morbidity is infrequent, and with modern techniques the incidence of treatment-related small bowel obstruction is around 5%. Radiotherapy to the abdomen and pelvis has also a potential role as consolidative treatment in patients with advanced disease, following a favourable response to chemotherapy.

Combined modality treatment using BID radiation for locally advanced non-small cell lung carcinoma

BACKGROUND

From February 1988 to August 1991, 82 patients were treated on Phase II trial of split-course multimodality treatment for locally advanced, non-small cell lung cancer (NSCLC).

METHODS

Treatment consisted of twice-daily radiation (150 cGy/fraction) delivered with concomitant infusional cisplatin, etoposide, and fluorouracil for 1 week every third week. Patients were classified before initial treatment as either potentially resectable (eligible for surgery [ES]) or ineligible for surgery (IES). The ES group consisted of 38 Stage IIIA and 7 Stage IIIB patients. The IES group had 5 patients staged as IIIA and 32 staged as IIIB. Most patients were staged clinically. ES patients received three cycles of treatment (39 Gy) before resection. IES patients received four cycles (60 Gy) delivered with curative intent.

RESULTS

Thirty-nine of 45 ES patients underwent resection. The pathologic response rate was 27%. Three-year actuarial local control was 86% for 41 evaluable ES patients. Three-year actuarial survival for the whole ES group was 39%, with a median follow-up for living patients of 32 months. The IES group faired less well, with an 18% 3-year actuarial survival. Treatment was well tolerated with a median weight loss of one-half pound, mild or moderate pneumonitis in 5%, mild esophagitis in 15%, and severe nausea and/or vomiting in 10% of patients. Treatment-related mortality was 5%.

CONCLUSIONS

Patients treated with conventional radiation alone for Stage III NSCLC are rarely cured. This well tolerated Phase II study demonstrated encouraging results for such patients. Both local control and survival appeared promising, especially in patients rendered resectable after combined-modality treatment.

Improvement of combined modality therapy with cisplatin and radiation using intratumoral drug administration in murine tumors

The aim of these studies was to increase the therapeutic ratio by achieving higher tumor concentrations of cisplatin during the course of a fractionated irradiation treatment. Specific goals were to test, firstly, whether multiple drug injections could be replaced by a single slow release implant of cisplatin, and secondly, whether the therapeutic potential of the combined treatment could be increased by administering the drug intratumorally. Drug administration routes tested were intraperitoneal (i.p.) of drug in solution, intratumoral (i.t.) of drug in solution, and intratumoral of drug in a slow release formulation. The latter consisted of a hydrogel polymer formulated into rods which were implanted into the center of subcutaneous tumors. For drug alone, both i.t. routes (solution or polymer) produced higher therapeutic gains than i.p. administration, as judged by tumor growth delay for a given weight loss. When combined with radiation, dose response curves were always shifted to lower doses and were steeper than for radiation or drug alone, although isobologram analysis indicated additivity. In a first series, drug enhancement ratios ranged from 1.6 to 2.6, and were highest for the i.t. groups. In a second series, X-ray enhancement ratios ranged from 1.1 to 1.7, with overlap between results from the different routes. Therapeutic ratios, however, were highest for the i.t. groups in both series. Slow release rods produced the highest therapeutic gains in the first series, while i.t. administration of drug in solution was approximately as effective in the second series.(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized study of chemotherapy, radiation therapy, and surgery versus surgery for localized squamous cell carcinoma of the esophagus

BACKGROUND

Despite well-established surgical approaches, the prognosis for patients with squamous cell carcinoma of the esophagus remains dismal. To assess the benefit of adjuvant chemotherapy and radiation therapy (CRT), a randomized trial with and without sequential preoperative CRT was undertaken; CRT combined 20 Gy and two courses of 5-FU and cisplatin.

METHODS

Patients were included on the basis of the following criteria: squamous cell carcinoma of the esophagus, younger than 70 years of age, World Health Organization status below 2, estimated survival time greater than 3 months, and no previous treatment for the cancer. Patients were not included if they had experienced a loss in body weight greater than 15% or had tracheoesophageal fistula, metastases, or uncontrollable infection.

RESULTS

Eighty-six patients thus fulfilled the criteria for inclusion (41 CRT, 45 non-CRT). The groups were well-matched for age, sex, tumor location, size, and grade. Operative mortality was 8.5% and 7%, respectively, for each group with a 27-day hospital stay for both groups. Long-term survival was not significantly different, with 47% of both groups alive at 1 year.

CONCLUSIONS

The authors concluded that this neoadjuvant treatment did not change operative mortality or survival time for patients with squamous cell carcinoma of the esophagus.

A randomized study of chemotherapy, radiation therapy, and surgery versus surgery for localized squamous cell carcinoma of the esophagus

BACKGROUND

Despite well-established surgical approaches, the prognosis for patients with squamous cell carcinoma of the esophagus remains dismal. To assess the benefit of adjuvant chemotherapy and radiation therapy (CRT), a randomized trial with and without sequential preoperative CRT was undertaken; CRT combined 20 Gy and two courses of 5-FU and cisplatin.

METHODS

Patients were included on the basis of the following criteria: squamous cell carcinoma of the esophagus, younger than 70 years of age, World Health Organization status below 2, estimated survival time greater than 3 months, and no previous treatment for the cancer. Patients were not included if they had experienced a loss in body weight greater than 15% or had tracheoesophageal fistula, metastases, or uncontrollable infection.

RESULTS

Eighty-six patients thus fulfilled the criteria for inclusion (41 CRT, 45 non-CRT). The groups were well-matched for age, sex, tumor location, size, and grade. Operative mortality was 8.5% and 7%, respectively, for each group with a 27-day hospital stay for both groups. Long-term survival was not significantly different, with 47% of both groups alive at 1 year.

CONCLUSIONS

The authors concluded that this neoadjuvant treatment did not change operative mortality or survival time for patients with squamous cell carcinoma of the esophagus.

Radiation therapy with concomitant continuous infusion cisplatin for unresectable nonsmall cell lung carcinoma

PURPOSE

This pilot study was designed to test the tolerance and effectiveness of concurrent continuous infusion cisplatin and radiotherapy in the treatment of unresectable nonsmall cell lung (NSCL) cancer.

METHODS AND MATERIALS

Between July 1989 and July 1991, 92 consecutive patients with either medically or technically inoperable NSCL cancer were treated with thoracic radiotherapy and concomitant chemotherapy. Radiotherapy consisted of a total dose of 70 Gy delivered in 2 Gy daily fractions over 9 weeks with a planned 2-week break after 40 Gy. During the second week of each cycle of radiotherapy, cisplatin was administered, 20 mg/m2/day for 5 days as a continuous infusion. Eighty-five patients were evaluable.

RESULTS

Overall response rate was 81.7% (65.9% complete response). Medically operable patients were considered for curative surgical resection following 40 Gy and one cycle of chemotherapy; 11 patients underwent resection with 3/11 having no pathologic evidence of tumor. Median survival for all 85 patients was 11.4 months with a median follow-up of 27 months. Overall survival was 48.2%, 27.5%, and 25% at 12, 24, and 36 months, respectively. Survival was independent of tumor stage, histology and grade, and patient age and gender. Patients having a complete response (n = 54) had a 2-year survival of 42.1% compared to 3.2% for partial-responders and nonresponders (n = 31; p < 0.0001). Patients undergoing surgical resection (n = 11) had a 2-year survival of 75.8% compared to 20.6% for those treated with chemoradiotherapy alone (n = 74). Forty-eight patients have died of their disease. There were two treatment-related deaths, seven deaths of intercurrent disease and three of unknown causes. Eighteen of 25 patients alive at the time of analysis were without evidence of disease. Actuarial local control was 50.6% at 1 year, and 33.3% at 2 years. The distant failure rate was 47.8% at 2 years. Major acute toxicities, mainly hematologic or gastrointestinal, occurred in less than 10% of patients. Esophagitis was mild and infrequent (8.4%). Severe late pulmonary fibrosis occurred in 5.2% of patients and resulted in two treatment-related deaths.

CONCLUSION

Concomitant chemoradiotherapy was well tolerated, resulted in a high rate of local control, and in a survival benefit for patients demonstrating a complete response or going on to surgical resection. The incidence of distant metastases continues to be high and future strategies should be directed at improving systemic therapy.

Comparative evaluation of cisplatin and carboplatin sensitivity in endometrial adenocarcinoma cell lines

Platinum analogues are frequently used in the treatment of advanced or recurrent endometrial cancer. To study the sensitivity of endometrial cancer to cisplatin and carboplatin, we tested two long-established (RL95-2, KLE) and six new cell lines (UM-EC-1, UM-EC-2, UM-EC-3, UT-EC-2A, UT-EC-2B, UT-EC-3) using the 96-well-plate clonogenic assay. This assay has proven to be suitable for testing chemosensitivity of both adenocarcinoma and squamous cell carcinoma. The chemosensitivity was expressed as an IC50 value, the drug concentration causing 50% inhibition of clonogenic survival. IC50 values were obtained from dose-response curves after fitting the data by the linear quadratic equation, F = exp[-(alpha D + beta D2)]. The IC50 values of the two platinum derivatives varied considerably. The values for cisplatin varied between 0.022 microgram ml-1 and 0.56 microgram ml-1 and the corresponding values for carboplatin were 0.096-1.20 microgram ml-1. The range of the ratios between carboplatin IC50 and cisplatin IC50, from 1.5:1 to 4.4:1, was rather narrow. However, no constant ratio between carboplatin IC50 and cisplatin IC50 could be detected. The equivalent doses with regard to efficacy of these two platinum analogues remain to be determined.

Radiosensitization by cytotoxic drugs. The EORTC experience by the Radiotherapy and Lung Cancer Cooperative Groups

A three-arm randomized trial was performed to assess the acute and late toxicity and the impact on survival of the combination high-dose, split-course radiotherapy with 30 mg/m2 cisplatin (cDDP) weekly, with 6 mg/m2 cisplatin daily compared to radiotherapy alone in patients with non-small cell lung cancer (NSCLC). The study started in May 1984 and was closed in May 1989 after 331 patients were randomised. The analysis was performed after a minimum follow-up period of 22 months. Radiotherapy (RT) consisted of 30 Gy, 10 fractions, five fractions a week; then a 3-week split followed by 25 Gy in 10 fractions. Nausea and vomiting were increased for a majority of the patients in the combined treatment arms during treatment. There was no addition of bone marrow suppression, renal dysfunction or esophagitis. Increase of late radiation damage was not observed. Local control (= absence of local progression) was improved for patients treated according to the daily cisplatin arm. This has lead to an improvement in overall survival. There was no effect in time to distant metastasis due to the combined modality. The treatment influence was confirmed in the multivariate analysis.

CONCLUSION

local control and survival can be improved by combining radiotherapy with daily low-dose cisplatin in patients with inoperable NSCLC.

Binding characteristics of (-)-(R)-2-aminomethylpyrrolidine(1,1-cyclobutanedicarboxylato)-2-platin um(II) to DNA, RNA and protein molecules in HeLa cells and its lethal effect: comparison with cis- and trans-diamminedichloroplatinums(II)

HeLa S-3 cells were treated with 195mPt-radiolabeled (-)-(R)-2-aminomethylpyrrolidine(1,1-cyclobutanedicarboxylato++ +)-2-platinum(II) (DWA2114R) under various conditions, and the relationship between the lethal effect of the agent and the number of platinum (Pt) atoms binding to DNA, RNA and proteins was examined. The values of mean lethal concentration for the cells treated with DWA2114 at 37 degrees C for 1, 2 and 3 h were 137.3, 75.10 and 51.17 microM, respectively. Cells were treated identically and the numbers of Pt atoms combined with DNA, RNA and protein molecules were determined after fractionation of the cells. In this way, the D0 values (D0, dose that would give an average of one lethal event per member of the population), expressed as the drug concentration, were substituted for the number of Pt atoms combined with each fraction. The target volumes, the efficacy of Pt atom to kill cells expressed as the reciprocals of the D0 values, were then calculated for each fraction. Our findings suggested that DNA was the primary target molecule for cell killing by DWA2114R. The target volumes for DNA were 3.36 x 10(4), 4.00 x 10(4) and 4.10 x 10(4) nucleotides for 1-, 2- and 3-h treated cells, respectively. The cell-killing effects of DWA2114R were lower than those of cis-diamminedichloroplatinum(II) (CDDP) by factors of 1.54, 1.42 and 2.51 for 1-, 2- and 3-h treatments at 37 degrees C, respectively, in terms of the target volume, while those in terms of the mean lethal dose (D0) were 14.8, 11.2 and 16.0, respectively. The efficacy of DWA2114R in killing the cells was 2.6 times greater than that of CDDP in the 3-h treatment at 0 degrees C.

Chemotherapy for cranial base tumors

The tumors I will discuss in this chapter on chemotherapy will be ethesioneuroblastoma, salivary gland tumors, chordoma and nasopharyngeal carcinoma. Due basically to the rarity of these lesions, with the exception of nasopharyngeal carcinoma, there have been no multi-institutional studies of chemotherapy use reported in the literature. As a result, there is no clear-cut consensus on the standard of care as it relates to chemotherapy for these tumors. As with most authors who have previously reviewed these tumor types, I believe it is important for us to propose protocols of therapy and test these in arenas where we can accumulate enough patients for meaningful results. In this way, we can test the apparently active agents and combinations in relapsed or extensive disease. We might also begin to explore concurrent therapy (i.e., concurrent radiation and chemotherapy after the surgical procedure, for example).

Proteins binding to cisplatin-damaged DNA in human cell lines

Cisplatin (CDDP) is a highly effective, frequently used cancer chemotherapeutic drug employed in the treatment of several human malignancies including ovarian, testicular, and bladder cancers. A common problem encountered with cisplatin therapy is intrinsic or acquired resistance to this drug. While the mechanisms of resistance to cisplatin, and other chemotherapeutic agents, are not fully understood, one factor affecting the cellular response to CDDP may result from differences in the level of specific proteins that recognize CDDP-damaged DNA. We have developed a damaged DNA affinity precipitation technique that allows the direct visualization and characterization of cellular proteins that bind to cisplatin-damaged DNA. In the present study we have utilized this method to analyze proteins present in several mammalian cell lines that bind to cisplatin-damaged DNA. We demonstrate that HeLa cells, resistant to CDDP cytotoxicity, contain high levels of high-mobility-group proteins 1 and 2, which bind to CDDP-DNA. We also show that xeroderma pigmentosum cells of different genetic complementation groups contain variable levels of a 45-kDa protein that binds to CDDP-DNA. Thus, our results indicate that different human cell lines demonstrate qualitative and quantitative differences in the expression of cisplatin-damaged DNA binding proteins.

Radiosensitization by nickel lapachol

The properties of interest in the radiosensitization of a metal complex, nickel lapachol, are compared with those of the 2-nitroimidazole, misonidazole. These very different compounds were found to be surprisingly similar in terms of their reduction potential (-370 mV), enhancement ratios for killing of hypoxic Chinese hamster ovary cells by X-irradiation, and enhancement of DNA breaks in hypoxia. For nitroimidazoles, the sensitization depends on 'electron affinity', reduction of the nitro group; for nickel lapachol it is the metal which is necessary for reduction, yet the sensitization efficiencies are remarkably close. However, the metal complex has additional activities (some sensitization in aerobic cells; increased sensitization with preincubation) which are as yet unexplained but are assumed to be related to the nature of the naphthoquinone ligand, rather than to the reduction of the metal.

Weekly cisplatin plus external beam radiotherapy and high dose rate brachytherapy in patients with locally advanced carcinoma of the cervix

PURPOSE

Prospective, single arm, Phase I/II trial performed to assess the efficacy and toxicity of the concomitant use of weekly cisplatin and pelvic radiotherapy in patients with locally advanced carcinoma of the cervix.

METHODS AND MATERIALS

Between December 1988 and April 1991, 50 previously untreated patients with bulky, locally advanced, squamous cell carcinoma entered the study. All patients were evaluated by a gynecologist and a radiation oncologist and were submitted to standard pre-treatment staging procedures. The International Federation of Gynecology and Obstetrics stage distribution was as follows: IIA three patients, IIB seventeen, IIIA two, IIIB 25, and IVA three. Radiotherapy consisted of 46 Gy external beam irradiation plus three high dose rate intracavitary treatments given on a weekly basis to a total dose of 30 Gy to point A. Cisplatin 30 mg/m2 was also given weekly starting on day 1 of radiotherapy.

RESULTS

With a median follow-up time of 27 months, complete response was seen in 88% (44/50) of the patients. The actuarial survival rate at 44 months was 65%. Total pelvic failure rate was 26% (13/50). Of the 44 patients who achieved a complete remission, only seven have failed in the pelvis. Distant disease was observed in 24% of the cases. Treatments were well tolerated with no patient requiring an interruption in the radiotherapy. However, the incidence of late gastrointestinal toxicity was high, with 10 patients developing a rectal ulcer (four colostomies for severe bleeding), two patients a small bowel obstruction, and two patients a recto-vaginal fistula. Moreover, gastrointestinal complications appeared sooner than expected, at a median follow-up time of 11 months after completion of treatment.

CONCLUSION

The combination of weekly cisplatin and radiotherapy appears to be a very effective regimen for patients with locally advanced carcinoma of the cervix, but resulted in a relatively high frequency of late gastrointestinal complications.