Cisplatin as a radiation sensitizer in the treatment of advanced head and neck cancers. Results of a phase II study

Circulating Tumour Cells (CTC), Head and Neck Cancer and Radiotherapy; Future Perspectives

Head and neck cancer is the seventh most common cancer in Australia and globally. Despite the current improved treatment modalities, there is still up to 50⁻60% local regional recurrence and or distant metastasis. High-resolution medical imaging technologies such as PET/CT and MRI do not currently detect the early spread of tumour cells, thus limiting the potential for effective minimal residual detection and early diagnosis. Circulating tumour cells (CTCs) are a rare subset of cells that escape from the primary tumour and enter into the bloodstream to form metastatic deposits or even re-establish themselves in the primary site of the cancer. These cells are more aggressive and accumulate gene alterations by somatic mutations that are the same or even greater than the primary tumour because of additional features acquired in the circulation. The potential application of CTC in clinical use is to acquire a liquid biopsy, by taking a reliable minimally invasive venous blood sample, for cell genotyping during radiotherapy treatment to monitor the decline in CTC detectability, and mutational changes in response to radiation resistance and radiation sensitivity. Currently, very little has been published on radiation therapy, CTC, and circulating cancer stem cells (CCSCs). The prognostic value of CTC in cancer management and personalised medicine for head and neck cancer radiotherapy patients requires a deeper understanding at the cellular level, along with other advanced technologies. With this goal, this review summarises the current research of head and neck cancer CTC, CCSC and the molecular targets for personalised radiotherapy response.

Oridonin Enhances Radiation-Induced Cell Death by Promoting DNA Damage in Non-Small Cell Lung Cancer Cells

Although many attempts have been made to improve the efficacy of radiotherapy to treat cancer, radiation resistance is still an obstacle in lung cancer treatment. Oridonin is a natural compound with promising antitumor efficacy that can trigger cancer cell death; however, its direct cellular targets, efficacy as a radiosensitizer, and underlying mechanisms of activity remain unclear. Herein, we report that oridonin exhibits additive cytotoxic and antitumor activity with radiation using the H460 non-small cell lung cancer cell lines. We assessed the effect of oridonin by proliferation, clonogenic, reactive oxygen species (ROS) production, DNA damage, and apoptosis assays. In vitro, oridonin enhanced the radiation-induced inhibition of cell growth and clonogenic survival. Oridonin also facilitated radiation-induced ROS production and DNA damage and enhanced apoptotic cell death. In vivo, the combination of oridonin and radiation effectively inhibited H460 xenograft tumor growth, with higher caspase-3 activation and H2A histone family member X (H2AX) phosphorylation compared with that of radiation alone. Our findings suggest that oridonin possesses a novel mechanism to enhance radiation therapeutic responses by increasing DNA damage and apoptosis. In conclusion, oridonin may be a novel small molecule to improve radiotherapy in non-small cell lung cancer.

Outcome and histopathologic regression in oral squamous cell carcinoma after preoperative radiochemotherapy

BACKGROUND AND PURPOSE

Preoperative radiochemotherapy has been reported to enhance tumor response and to improve long-term survival in advanced squamous cell carcinoma of the head and neck. This retrospective study evaluates regression rate and long-term survival in 228 patients with primary oral squamous cell carcinoma treated by neoadjuvant radiochemotherapy and radical surgery.

PATIENTS AND METHODS

All patients with biopsy-proven, resectable oral squamous cell carcinoma - TNM stages II-IV without distant metastasis - received preoperative treatment consisting of fractioned irradiation of the primary and the regional lymph nodes with a total dose of 40 Gy and additional cisplatin (n = 160) or carboplatin (n = 68) during the 1st week of treatment. Radical surgery and neck dissection followed after a delay of 10-14 days. The study only included cases with histologically negative resection margins.

RESULTS

After a median follow-up of 5.2 years, 53 patients (23.2%) had experienced local-regional recurrence. The median 2-year disease-specific survival (DSS) rate was 86.2%. 5-year DSS and 10-year DSS were 76.3% and 66.7%, respectively. Complete histological local tumor regression after surgery (ypT0) was observed in 50 patients (21.9%) and was independent of pretreatment tumor classification. Uni- and multivariate survival analysis revealed that ypT- and ypN-stage were the most decisive predictors for DSS.

CONCLUSION

Preoperative radiochemotherapy with cisplatin/carboplatin followed by radical surgery attains favorable long-term survival rates. This applies especially to cases with complete histological tumor regression after radiochemotherapy, which can be assumed for one of five patients.

Concurrent chemoradiotherapy with weekly paclitaxel and carboplatin for locally advanced head and neck cancer: Long-term follow-up of a Brown University Oncology Group Phase II Study (HN-53)

BACKGROUND

A phase II study was conducted using concurrent paclitaxel, carboplatin, and external beam radiotherapy (RT) in patients with advanced head and neck cancer.

METHODS

Forty-three patients (stage III, n = 12; stage IV, n = 31) were treated with 8 cycles of weekly paclitaxel (60 mg/m(2)), carboplatin (area under the curve [AUC] = 1), and RT (1.8 Gy daily; total dose, 66-72 Gy). Patients with initially palpable lymph nodes underwent neck dissection.

RESULTS

The overall clinical response rate was 91% (65% complete, 26% partial). Severe mucositis occurred in 37 (90%) patients, necessitating hospitalization in 13 (31%) patients. With a median follow-up of 49 months, the locoregional and distant failure rates were 26% and 21%, respectively.

CONCLUSIONS

Concurrent paclitaxel, carboplatin, and RT for advanced head and neck cancer results in high complete response rates. Long-term follow-up has revealed the curative potential of this regimen, though the doses used resulted in unacceptable toxicity.

Preoperative chemoradiotherapy in the management of oral cancer: a review

INTRODUCTION

Multi-modality treatment concepts involving preoperative radiotherapy (RT) or chemoradiotherapy (CRT) and subsequent radical resection are used much less frequently than postoperative treatment for oral and oropharyngeal squamous cell carcinomas. In some centres, however, the preoperative approach has been established for several years.

MATERIAL

The present review is a compilation of the existing evidence on this subject.

METHODS

In a literature-based meta-analysis, the survival data of 1927 patients from 32 eligible publications were analysed.

RESULTS

The calculated survival rates of documented patients show remarkably good results with preoperative CRT and radical surgery. However, the findings of this analysis are based on data with a large proportion of studies using consecutive patient series.

CONCLUSION

Hard evidence providing sufficient data from prospective randomised studies is as yet missing for preoperative CRT. Prospective randomised studies are mandatory in this area.

Prognostic value of response to preoperative chemoradiotherapy and residual tumor grades in tongue carcinoma

OBJECTIVE

The purposes of the present study were to analyze our experience with preoperative chemoradiotherapy followed by surgery for advanced tongue carcinoma and to assess the prognostic value of response to preoperative therapy in these tumors.

STUDY DESIGN

Between May 1988 and December 1999, a total of 43 patients with advanced but potentially resectable squamous cell carcinoma of the tongue were candidates for this study. A minimum tumor size of 3 cm was required. The mean age was 59.8 years (range, 26-85 years); 13 cases were advanced stage II, 23 cases were stage III, and 7 cases were stage IV. All patients were treated preoperatively with cisplatin- or carboplatin-based chemotherapy in combination with simultaneous irradiation to a target volume of 40 Gy; 2-6 weeks later, they underwent curative surgery. Tumor regression rate, residual tumor grade, and histologic regression grade to the preoperative therapy were analyzed to determine their influence on the prognosis.

RESULTS

With a median follow-up of 60.5 months, overall survival rates were 86.0% for all cases, 92.3% for stage II cases, 77.3% for stage III cases, and 100% for stage IV cases. The progression-free survival rates according to tumor regression rate were 33.3% for group 1 (< 50% tumor regression), 66.7% for group 2 (> or = 50% and < 75% regression), 100% for group 3 (> or = 75% and < 100% regression), and 96.0% for group 4 (complete regression). The higher the tumor regression rates, the higher the survival rates. When patients who achieved a regression rate of 75% or higher were compared with those who did not, there was a significant difference in survival (P < .0001). The factors of residual tumor grade and histologic regression grade also had good correlations with the prognosis (residual tumor grade, P =.0324; histologic regression grade, P < .0001).

CONCLUSIONS

The findings of the present study suggest that response to preoperative chemoradiotherapy, such as tumor regression rate, residual tumor grade, and histologic regression grade, could be of prognostic value in patients with tongue carcinoma.

Remission of bone metastases after combined chemotherapy and radionuclide therapy with Re-186 HEDP

A patient with disseminated osseous metastases due to breast cancer reported multifocal pain. Because of persisting pain after a first cycle of chemotherapy, 1,295 MBq Re-186 HEDP was administered intravenously. Excellent pain relief was observed. Subsequently, the patient received further combined chemotherapy and Re-186 HEDP therapy and remained pain free. Tc-99m MDP bone imaging showed a significant regression of osseous metastases. It may be speculated that the combination of Re-186 HEDP and chemotherapy results in significantly increased palliation of metastatic bone disease.

A phase II trial, feasibility of combination of daily cisplatinum and accelerated radiotherapy via concomitant boost in stage III non-small cell lung cancer

PURPOSE

A prospective phase II trial was conducted by the Institute of Oncology, Istanbul University in December 1994 on patients with locally-advanced non-small cell lung cancer to assess acute toxicity and the feasibility of a combination of radiosensitizer and accelerated radiotherapy with concomitant boost.

MATERIALS AND METHODS

Patients were irradiated using 'large' fields (primary tumour and locoregional lymph nodes) with 1.8 Gy per fraction, five fractions a week. Reduced 'boost' fields (primary and involved nodes only) were also irradiated twice-weekly 1.8 Gy per fraction in ten fractions concomitantly 6 h after the administration of large field. Total radiation dose was 63 Gy in 5 weeks (45 Gy 'large' fields and 18 Gy 'boost'). The maximum allowed dose to the spinal cord was 3750 cGy. Cisplatinum, 6 mg/m2 was given daily just before 'large' field irradiation.

RESULTS

As of January 1997, 15 patients were evaluated (median follow-up of 12.5 months with a range of 5.5-23 months). The overall acute toxicity rate was 38% and Grade 3 acute toxicity was 8%. Grade 4 or greater acute toxicities were not observed. The overall rate of cisplatinum-induced nausea and vomiting was 80% (severe in 60%), but all were easily treated with antiemetics. Complete response rate (clinical and radiological) was 40% and an overall response rate was 73%. Median survival was 16 months and progression-free survival was 5.5 months (range of 2.5-21 months).

CONCLUSIONS

Toxicity was well tolerated and no treatment-related death occurred with this combined treatment regimen. Although it appears that better local control rates can be achieved, additional phase II/III studies are needed.

Oral platinum analogue JM216, a radiosensitizer in oxic murine cells

This study was designed to compare radiosensitization by the oral platinum compound JM216 with cisplatin. RIF1 mouse tumour cells were treated at various doses and at various exposure times with JM216 and irradiated 15 min before the end of drug exposure. The fraction of cells surviving treatment was assessed by colony formation. Results were compared with those for equivalent treatments with cisplatin. JM216 alone showed exponential killing of RIF1 cells, being approximately three times less efficient than cisplatin on a molar basis. For radiosensitization studies, drug doses used gave approximately 50 or 90% cell killing alone. No radiosensitization was seen after 2-h drug exposures, but significant radiosensitization occurred after 1- and 0.5-h exposures (shorter times required proportionally higher drug doses, giving equivalent drug kill). The enhancement ratio and time dependence were similar for the two platinum compounds, reaching 1.5 at the highest concentrations tested. Drug DNA adduct formation was assessed using immunocytochemistry with the NKI-A59 antiserum raised to cisplatin-DNA adducts. The antiserum was shown to recognize JM216-DNA adducts in a dose-dependent manner and maximum nuclear staining was found to be correlated with cell kill for both drugs. However, neither the level of staining at the time of irradiation nor at the time of maximum adducts correlated with radiosensitization, indicating that the number of DNA adducts did not determine radiosensitization. Intracellular glutathione levels were shown to be decreased by the drug, but only by approximately 50%, implying that this was not the cause of the increased radiosensitivity. In summary, JM216 was shown capable of radiosensitizing a platinum-sensitive tumour line to an extent similar to cisplatin. Radiosensitization was exposure-time and drug-concentration dependent, but was not dependent on DNA adduct levels nor glutathione depletion. In contrast, cell kill after drug alone was well correlated with adduct levels. These data suggest that JM216 could replace cisplatin in combined radiotherapy-chemotherapy studies, and also indicate that the NKI-A59 antibody could be used to monitor exposure levels in vivo.

Interactions between outcomes and tumor response to preoperative cisplatin-sensitized radiotherapy in advanced head and neck cancer. Southern New Jersey Head and Neck Cancer Treatment Group

BACKGROUND

Whether or not tumor response to chemotherapy-sensitized radiation therapy (CTRT) for head and neck cancer leads to an improved outcome is unknown.

METHODS

Forty patients who received preoperative cisplatin plus simultaneous radiotherapy for operable stage III and IV head and neck cancer were reviewed retrospectively regarding clinical demographics, staging, and survival status.

RESULTS

Twenty-one (57%) patients had a histologic complete response (HCR) and 16 (43%) had a partial (PR) (9) or clinical complete (7) response (CCR). Tumor response of N1 versus N2-3 nodal disease showed 6 (75%) HCR and 4 (25%). Five-year disease-free survival overall was 82% for HCR versus 38% for PR/CCR (P <0.05). Disease-specific 5-year survival was 100% for HCR versus 27% for PR/CCR (P <0.002).

CONCLUSIONS

Histologic complete response to CTRT for head and neck cancer is associated with increased survival and encouraging disease-free status. Response to CTRT is inversely proportional to lymphatic tumor load.

Preoperative simultaneous cisplatin- or carboplatin-based chemotherapy and radiotherapy for squamous cell carcinoma of the oral cavity

BACKGROUND

Encouraging results have been reported with cisplatin- or carboplatin-based chemotherapy regimens and simultaneous irradiation treatment in advanced and unresectable head and neck head and neck cancer. We have therefore examined the effectiveness of such therapy on tumor control, survival, and toxicity in patients with advanced oral squamous cell carcinoma.

METHODS

Forty-one patients with squamous cell carcinoma of the oral cavity (including soft palate) were treated preoperatively with cisplatin or carboplatin, and 5-fluorouracil or peplomycin in combination with simultaneous irradiation to a target volume of 40Gy, and 2-6 weeks later, curative surgery was performed.

RESULTS

Thirty-eight patients (91.7%) had Stage III or IV disease, and three patients had Stage II lesions. The preoperative clinical responses of the primary tumor were: 25 patients (61.0%) achieved a complete response (CR), 15 (36.6%) a partial response (PR), only 1 patient (2.4%) had stable disease or no change (NC). The overall response rate was 97.6%. Histological effects according to the grading system of Shimosato and coworkers [Jpn J Clin Oncol 1:19-35, 1971] were seen in 38/41 (92.7%). Of clinical CR patients, 73.9% were also histologic negative for tumor. Side effects of this therapy were relatively low and reversible. With a median follow-up of 52.8 months (range 17-92 months), 5-year cumulative survival rates were 81.5% for all patients, 100% for Stage II, 88.6% for Stage III, and 76.4% for Stage IV patients, respectively. There was no significant postoperative morbidity.

CONCLUSIONS

This preoperative chemoradiotherapy regimen was highly active, well tolerated, and appeared to have a survival benefit even for advanced carcinomas of the oral cavity.

Enhanced acute toxicity in oropharynx carcinoma treated with radiotherapy and concomitant cisplatin, 5-fluorouracil and mitomycin C

The aim of this study was to establish the feasibility of giving concomitant radiotherapy and 3 cycles of chemotherapy with cisplatin (CDDP), 5-fluorouracil (5-FU) and mitomycin C (MMC) in locally advanced inoperable oropharyngeal cancer. From March 1990 to September 1993, 27 male patients (mean age 55 years) were included in this study. 3 patients (11%) were T2N0, 19 (70%) T3 (T3N0: n = 9, T3N1: n = 1, T3N2: n = 5, T3N3: n = 4), and 5 (19%) T4 (T4N0: n = 1, T4N1: n = 1, T4N2: n = 2, T4N3: n = 1). All patients received conventional radiotherapy delivering 70 Gy in 35 fractions and 52 days, and three cycles of chemotherapy starting on day 1, 21 and 42 with CDDP 20 mg/m2 and 5-FU 400 mg/m2 day 1 to day 4, and MMC 10 mg/m2 day 1. With a mean follow-up of 34 months (17-59), 10 patients (37%) were alive and free of disease. Among the 17 other patients, 8 died of cancer. Crude locoregional control rate was 78%, and probability of local control at 1 and 2 years was 85 and 80%, respectively. One- and 2-year survival rates were 48 and 31%, respectively, for both overall and disease-free survival. Grade 3 or 4 mucositis occurred in 22 patients (81%); enteral feeding was necessary for 63%; mean weight loss was 5.7 kg. Grade > 2 thrombocytopenia occurred in 11 patients (41%), grade > 2 neutropenia in 8 patients (29%), grade > 2 anaemia in 4 patients (15%). Febrile neutropenia or aplasia occurred in 5 patients (19%). 2 patients (7%) died during treatment of haematological or infectious complications related to the treatment. Another patient died 1 month after treatment with grade 4 thrombocytopenia and septicaemia. In conclusion, a high complete response rate has been achieved with this concomitant chemo- and radiotherapy, but with severe digestive and haematological toxicity. Addition of MMC to 5-FU and CDDP might have been responsible for this increased toxicity. This therapeutic combination is therefore not routinely feasible.

Tumour cells surviving in vivo cisplatin chemotherapy display elevated c-myc expression

The c-myc oncogene has been extensively implicated in cell proliferation, cell differentiation and programmed cell death. Aberrant expression of the c-myc gene product has been observed in a range of tumours and has also been implicated in cisplatin (cis-dichlorodiammineplatinum)-mediated chemoresistance. A solid transplantable tumour model in syngeneic DA rats was subjected to treatment with cisplatin to determine the impact of such therapy on endogenous c-myc gene expression. Serially transplanted tumours were intravenously treated with a single cisplatin dose (1 mg/kg) and c-myc expression analysed 2 and 7 days after treatment. The surviving tumour cells display a significant 2-fold elevation in c-myc expression at 48 h and 7 days after treatment. Primary cell cultures have been derived from untreated in vivo tumours of the same model and subjected to treatment with a c-myc phosphorothioate antisense oligomer. Administration of 5 microM c-myc antisense oligomer directed at the initiation codon and first four codons of c-myc mRNA results in total inhibition of c-myc expression and coincident suspension of cell growth for a period of 4 days in culture. Antisense therapies directed at the c-myc gene may well prove an effective tool for treating tumours in conjunction with cisplatin as these findings show that tumour cells surviving cisplatin chemotherapy display elevated c-myc expression.