Determination of tumor kinetics: strategies for the delivery of radiotherapy and chemotherapy

Phase II trial evaluating the feasibility of interdigitating folfox with chemoradiotherapy in locally advanced and metastatic rectal cancer

BACKGROUND

Patients (pts) with metastatic rectal cancer and symptomatic primary, require local and systemic control. Chemotherapy used during chemoradiotherapy (CRT) is adequate for radiosensitisation, but suboptimal for systemic control. The aim of this phase II study was to assess tolerability, local/systemic benefits, of a novel regimen delivering interdigitating intensive chemotherapy with radical CRT.

METHODS

Eligible pts had untreated synchronous symptomatic primary/metastatic rectal cancer. A total of 12 weeks of treatment with split-course pelvic CRT (total 50.4 Gy with concurrent oxaliplatin and 5-FU infusion) alternating with FOLFOX chemotherapy. All pts staged with CT, MRI and FDG-PET pre and post treatment.

RESULTS

Twenty-six pts were treated. Rectal primary MRI stage: T3 81% and T4 15%. Liver metastases in 81%. Twenty-four pts (92%) completed the 12-week regimen. All patients received planned RT dose, and for both agents over 88% of patients achieved a relative dose intensity of >75%. Grade 3 toxicities: neutropenia 23%, diarrhoea 15%, and radiation skin reaction 12%. Grade 4 toxicity: neutropenia 15%. FDG-PET metabolic response rate for rectal primary 96%, and for metastatic disease 60%.

CONCLUSIONS

Delivery of interdigitating chemotherapy with radical CRT was feasible to treat both primary and metastatic rectal cancer. High completion and response rates were encouraging.

The treatment of unresectable, locally advanced non-small-cell lung cancer: a radiation therapy perspective with an emphasis on the trials of the Radiation Therapy Oncology Group

Radiation therapy used as a single modality in the treatment of locally advanced non-small-cell lung cancer is potentially curative, but long-term survival rates are disappointing due to both locoregional and distant failures. The trials of the Radiation Therapy Oncology Group (RTOG) have been instrumental in defining the optimal management of this disease. The conclusions and questions posed by the RTOG are discussed in this review. The conclusions of this review include the following: chemotherapy combined with radiation therapy improves survival in patients with good performance, with increased toxicity; concurrent chemoradiation is superior to sequential chemoradiation. Questions remain regarding the value of the addition of induction or consolidation chemotherapy to concurrent chemoradiation, the value of three-dimensional conformal radiation therapy, the role of altered fractionation regimens in combination with chemotherapy, the optimal chemotherapeutic regimen, and the role of novel biologic agents.

Induction chemotherapy followed by radical local therapy for locally advanced non-small cell lung cancer

Many patients who receive a diagnosis of non-small cell lung cancer (NSCLC) have locally advanced disease at initial presentation. Historically, these patients were treated with primary thoracic radiation therapy and had poor long-term survival rates, secondary to both progression of local disease and development of distant metastases. With the goal of improving clinical outcomes, multiple concepts of combined-modality therapy for locally advanced NSCLC have been investigated. The rationale for using chemotherapy in the induction regimen is to eliminate subclinical metastatic disease while improving local control. The optimal treatment of locally advanced NSCLC continues to evolve, but combined-modality therapy has led to improved survival rates compared to treatment with radiation alone and has become the new standard of care. This report reviews the major trials that have investigated various combinations of surgery, radiation therapy, and chemotherapy in the treatment of locally advanced NSCLC.

Alternating chemoradiotherapy versus partly accelerated radiotherapy in locally advanced squamous cell carcinoma of the head and neck: results from a phase III randomized trial

BACKGROUND

The authors previously have found that in patients with locally advanced squamous cell carcinoma of the head and neck (SCC-HN), alternating chemoradiotherapy (ALT) was superior to low-total-dose conventional radiotherapy alone. The purpose of this randomized trial was to compare the same chemoradiotherapy approach with high-total-dose partly accelerated radiotherapy.

METHODS

During 6 years, 136 consecutive patients with previously untreated unfavorable Stage II or Stage III-IV (International Union Against Cancer) SCC of the oral cavity, pharynx, and larynx were enrolled. They were randomly assigned to chemotherapy consisting of 4 cycles of intravenous cisplatin (20 mg/m(2) of body surface area per day for 5 consecutive days) and 5-fluorouracil (200 mg/m(2) per day for 5 consecutive days; weeks 1, 4, 7, and 10) alternated with three 2-week courses of radiotherapy (20 grays [Gy] per course, 2 Gy per day, 5 days per week; ALT, 70 patients) or to partly accelerated radiotherapy with final concomitant boost technique (75 Gy/40 fractions in 6 weeks; partly accelerated radiotherapy [PA-RT], 66 patients).

RESULTS

At the median follow-up of 60 months (range, 30-102 months), no statistical differences were observed in overall survival, progression free survival, or locoregional control between the 2 treatments. Actuarial 3-year overall survival and progression free survival were 37% and 35%, respectively, in the ALT group and 29% and 27%, respectively, in PA-RT group. The median overall survival and progression free survival were 24 and 15 months, respectively, in the ALT arm and 18 and 11 months, respectively, in PA-RT arm. Actuarial 3-year locoregional control rates were 32% in the ALT group and 27% in the PA-RT group. At multivariate analysis, tumor classification was the only factor that emerged as a significant independent variable affecting overall survival. Patients treated in the PA-RT arm experienced higher Grade 3+ (World Health Organization) acute skin and mucosal reactions than patients in the ALT arm. Moreover, local late mucosal and skin toxicities occurred more often in patients treated with PA-RT.

CONCLUSIONS

This trial failed to disclose statistically significant differences in the outcome of patients treated with either ALT or PA-RT. Therefore, definitive conclusions could not be made. However, acute skin effects and late mucosal and skin toxicities above the clavicles appeared to be significantly lower with chemoradiotherapy.

Hamming clustering techniques for the identification of prognostic indices in patients with advanced head and neck cancer treated with radiation therapy

The aim of the study is to demonstrate the usefulness of a new, non-linear classifier method, called Hamming clustering (HC), in selecting prognostic variables affecting overall survival in patients with head and neck cancer. In particular, the aim is to identify whether tumour proliferation parameters can be predictive factors of response in a set of 115 patients that receive either alternating chemo-radiotherapy or accelerated or conventional radiotherapy. HC is able to generate a set of understandable rules underlying the study objective; it can also select a subset of input variables that represent good prognostic factors. HC has been compared with other standard classifiers, providing better results in terms of classification accuracy. In particular, HC obtains the best accuracy of 74.8% (sensitivity of 51.1% and specificity of 91.2%) about survival. The rules found show that, besides the classical, well-known variables concerning the tumour dimension and the involved lymphonodes, some biological parameters, such as DNA ploidy, are also useful as predictive factors.

Evidence of cell kinetics as predictive factor of response to radiotherapy alone or chemoradiotherapy in patients with advanced head and neck cancer

PURPOSE

The aim of this study was to investigate the potential clinical relevance of cell kinetics parameters to the locoregional control (LRC) and overall survival of patients affected by head and neck squamous cell carcinoma (HN-SCC) treated by conventional radiotherapy, partly accelerated radiotherapy, or alternating chemoradiotherapy.

METHODS AND MATERIALS

Between January 1993 and June 1996,115 patients with HN-SCC at Stage III and IV entered the study. Multiple primary tumor biopsies were obtained 6 h after in vivo infusion of bromodeoxyuridine (BrdUrd), an analogue of thymidine that is incorporated in DNA-synthesizing cells. In vivo S-phase fraction labeling index (LI), duration of S-phase (Ts), and potential doubling time (Tpot) were obtained by analysis of the flow cytometric content of BrdUrd and DNA. Eighty-two patients were randomly assigned to receive either alternating chemoradiotherapy or partly accelerated radiotherapy, whereas 33 other matching patients received conventional radiotherapy.

RESULTS

Univariate LRC analysis showed that LI value was a prognostically significant factor, independent of type of therapy. Multivariate analysis failed to show cell kinetics parameters as statistically significant factors affecting LRC probability and overall survival. However, subgroup analysis showed that LRC probability at 4 years for fast proliferating tumors characterized by a LI >/= 8% was significantly better for patients treated either with alternating chemoradiotherapy or partly accelerated radiotherapy than it was for those treated with conventional radiotherapy. Conversely, LRC probability for slow proliferating tumors (LI < 8%) treated with the three treatment modalities was similar.

CONCLUSIONS

These results showed that, independent of type of treatment, pretreatment cell kinetics provided only a weak prognostic role of outcome in HN-SCC. However, this report raises the hypothesis that fast growing HN-SCC may be more likely to benefit from intensified therapy, as given in this series. Cell kinetics parameters studied by the in vivo BrdUrd/flow cytometry method might be considered predictive factors of response, providing information on which type of treatment may be selected according to tumor proliferation rate.