Using treatment interruptions to palliate the toxicity from concurrent chemoradiation for limited small cell lung cancer decreases survival and disease control

GOECP/SEOR radiotherapy guidelines for small-cell lung cancer

Small cell lung cancer (SCLC) accounts for approximately 20% of all lung cancers. The main treatment is chemotherapy (Ch). However, the addition of radiotherapy significantly improves overall survival (OS) in patients with non-metastatic SCLC and in those with metastatic SCLC who respond to Ch. Prophylactic cranial irradiation reduces the risk of brain metastases and improves OS in both metastatic and non-metastatic patients. The 5-year OS rate in patients with limited-stage disease (non-metastatic) is slightly higher than 30%, but less than 5% in patients with extensive-stage disease (metastatic). The present clinical guidelines were developed by Spanish radiation oncologists on behalf of the Oncologic Group for the Study of Lung Cancer/Spanish Society of Radiation Oncology to provide a current review of the diagnosis, planning, and treatment of SCLC. These guidelines emphasise treatment fields, radiation techniques, fractionation, concomitant treatment, and the optimal timing of Ch and radiotherapy. Finally, we discuss the main indications for reirradiation in local recurrence.

Barriers affecting adherence to radiation treatment and strategies to overcome those barriers

BACKGROUND

The WHO defines adherence as the extent to which a patient's behavior coincides with recommendations from a health-care provider. Nonadherence to cancer treatment has a major impact on the therapeutic outcome.

AIM OF THE STUDY

To assess the prevalence of nonadherence to radiation regimen and to analyze the factors that affect adherence to cancer treatment.

MATERIALS AND METHODS

Patients receiving radiation treatment in our hospital were screened for adherence to appointment keeping and to the prescribed radiation regimen and patients who had unplanned treatment breaks during treatment were interviewed. Between January and July 2013, we identified 61 patients who had unplanned breaks during treatment. We analyzed the social, emotional, educational, economic, and therapeutic barriers that led to nonadherence.

RESULTS

Of the 61 patients who had unplanned breaks during treatment, 54% were males and 46% were females. Fifty-seven percent of patients had head and neck cancers and 25% had gynecological cancers. Seventy-one percent of patients were planned for concurrent chemoradiation. The number of days of unplanned treatment breaks ranged from 3 to 27 days. Social and therapeutic barriers were found to be the most common factor that led to nonadherence in these patients.

CONCLUSION

Identification of barriers that lead to nonadherence, designing strategies to overcome such barriers and effective communication becomes imperative to ensure uninterrupted treatment. Based on the above analysis, we have designed several strategies to improve adherence to treatment among our patients.

Duration of Twice-Daily Thoracic Radiotherapy and Time From the Start of Any Treatment to the End of Chest Irradiation as Significant Predictors of Outcomes in Limited-Disease Small-Cell Lung Cancer

BACKGROUND

The hypothesis of this retrospective study was that the duration of twice-daily (BID) thoracic radiotherapy (TRT) and time from the start of any treatment to the end of chest irradiation (SER) would predict outcomes in limited-disease small-cell lung cancer.

MATERIALS AND METHODS

All 81 patients received 45 Gy in 30 fractions BID with a ≥ 6-hour interval and concurrent chemotherapy of platinum and etoposide.

RESULTS

The median radiotherapy duration was 25 days (range, 21-38 days). The 5-year overall survival rates were 26.2% (95% confidence interval [CI], 14.3%-38.0%), and the median survival time was 30 months (95% CI, 15.5-44.5 months). Using multivariate regression analysis, the significant predictors of survival were the sum of the diameters of the primary tumor and metastatic lymph nodes, male gender, age ≥ 60 years, and the duration of BID-TRT (hazard ratio [HR], 1.15; 95% CI, 1.06-1.25; HR, 2.38; 95% CI, 1.13-5.02; HR, 2.38; 95% CI, 1.10-5.17; and HR, 1.08; 95% CI, 1.01-1.15, respectively). A total of 70 of 81 patients (86%) received radiotherapy during the first chemotherapy cycle. The median SER was 29 days (range, 21-109 days). The 5-year local control rate was 48.7% (95% CI, 33.9%-63.6%). The significant predictors of local control were the sum of the diameters of the primary tumor and metastatic lymph nodes, age ≥ 60 years, and SER (HR, 1.18; 95% CI, 1.06-1.31; HR, 4.18; 95% CI, 1.23-14.24; and HR, 1.02; 95% CI, 1-1.04, respectively).

CONCLUSIONS

The duration of BID-TRT and SER were identified as one of the significant predictors of survival and local control in limited-disease small-cell lung cancer treated with concurrent chemoradiotherapy at 45 Gy in 30 fractions, respectively.

Phase 2 study of accelerated hypofractionated thoracic radiation therapy and concurrent chemotherapy in patients with limited-stage small-cell lung cancer

PURPOSE

To prospectively investigate the efficacy and toxicity of accelerated hypofractionated thoracic radiation therapy (HypoTRT) combined with concurrent chemotherapy in the treatment of limited-stage small-cell lung cancer (LS-SCLC), with the hypothesis that both high radiation dose and short radiation time are important in this setting.

METHODS AND MATERIALS

Patients with previously untreated LS-SCLC, Eastern Cooperative Oncology Group performance status of 0 to 2, and adequate organ function were eligible. HypoTRT of 55 Gy at 2.5 Gy per fraction over 30 days was given on the first day of the second or third cycle of chemotherapy. An etoposide/cisplatin regimen was given to 4 to 6 cycles. Patients who had a good response to initial treatment were offered prophylactic cranial irradiation. The primary endpoint was the 2-year progression-free survival rate.

RESULTS

Fifty-nine patients were enrolled from July 2007 through February 2012 (median age, 58 years; 86% male). The 2-year progression-free survival rate was 49.0% (95% confidence interval [CI] 35.3%-62.7%). Median survival time was 28.5 months (95% CI 9.0-48.0 months); the 2-year overall survival rate was 58.2% (95% CI 44.5%-71.9%). The 2-year local control rate was 76.4% (95% CI 63.7%-89.1%). The severe hematologic toxicities (grade 3 or 4) were leukopenia (32%), neutropenia (25%), and thrombocytopenia (15%). Acute esophagitis and pneumonitis of grade ≥3 occurred in 25% and 10% of the patients, respectively. Thirty-eight patients (64%) received prophylactic cranial irradiation.

CONCLUSION

Our study showed that HypoTRT of 55 Gy at 2.5 Gy per fraction daily concurrently with etoposide/cisplatin chemotherapy has favorable survival and acceptable toxicity. This radiation schedule deserves further investigation in LS-SCLC.

The effect of bioequivalent radiation dose on survival of patients with limited-stage small-cell lung cancer

Background

To investigate the biological radiation dose-response for patients of limited-stage small-cell lung cancer (LS-SCLC) treated with high radiation dose.

Methods

Two hundred and five patients of LS-SCLC treated with sequential chemotherapy and thoracic radiotherapy with involved-field between 1997 and 2006 were reviewed retrospectively. Biologically effective dose (BED) was calculated for dose homogenization and was corrected with the factor of overall radiation time. Patients were divided into low BED group (n = 70) and high BED group (n = 135) with a cut-off of BED 57 Gy (equivalent to 60 Gy in 30 fractions over 40 days). Outcomes of the two groups were compared.

Results

Median follow-up was 20.7 months for all analyzable patients and 50.8 months for surviving patients. Considering all patients, median survival was 22.9 months (95% confidence interval, 20.6-25.2 months); 2- and 5-year survival rates were 47.2% and 22.3%, respectively. Patients in high BED group had a significantly better local control (p = 0.024), progression-free survival (p = 0.006) and overall survival (p = 0.005), with a trend toward improved distant-metastasis free survival (p = 0.196). Multivariable Cox regression demonstrated that age (p = 0.003), KPS (p = 0.009), weight loss (p = 0.023), and BED (p = 0.004) were significant predictors of overall survival.

Conclusions

Our data showed that a high BED was significantly associated with favourable outcomes in the Chinese LS-SCLC population, indicating that a positive BED-response relationship still existed even in a relatively high radiation dose range.

Prolongation of total treatment time because of infrequently missed days of treatment is not associated with inferior biochemical outcome after dose-escalated radiation therapy for prostate cancer

PURPOSE

Prolongation of treatment time with radiation therapy (RT) is associated with inferior disease control for many rapidly proliferating tumors, but it is uncertain whether the same effect is seen in prostate cancer.

METHODS AND MATERIALS

596 patients underwent with curative-intent RT for adenocarcinoma of the prostate. By National Comprehensive Cancer Network criteria, men were classified as having low-risk (30%), medium-risk (40%), or high-risk (30%) disease. The median RT dose was 72 Gy. Androgen-deprivation therapy (ADT) was used in 45%. The idealized treatment time was defined as the total elapsed time (including weekends) to complete treatment if started on a Monday. Missed days of treatment, defined as the number of days beyond the idealized treatment time, was recorded for all patients. Missed days were added to the end of therapy resulting in a longer treatment time. Analysis was conducted for missed days and other standard prognostic variables against freedom from biochemical failure (FFBF).

RESULTS

The median number of missed days was 2 (range, -3 to 22). With a median follow-up of 51 months, men with 5 or more missed days had similar 4-year FFBF rates (79% vs. 83% in men with <5 missed days, p = 0.0809), especially in the subset of men receiving 74 Gy or greater (89% for both groups, p = 0.8008). Analysis of missed days was performed for the subsets of dose, ADT, and risk category. Men without ADT had a lower FFBF rate with more missed days (p = 0.0030), but this association was not seen in men treated to a dose of 74 Gy or greater (p = 0.7425). On multivariate analysis, dose (p = 0.0010), T stage (p = 0.0145), and prostate-specific antigen level (p < 0.0001) were associated with FFBF, but Gleason score (p = 0.1351) and missed days (p = 0.3767) were not.

CONCLUSIONS

Slight prolongation of treatment time (e.g., ≤7 days) was not associated with inferior FFBF, especially in men receiving an RT dose of 74 Gy or greater.

Treatment interruption and discontinuation in radiotherapy for rectal cancer

Radiotherapy with chemotherapy for rectal cancer reduces local recurrence risk. Of 113 patients (59 male, 54 female) undergoing treatment at New York Presbyterian Hospital, 1998-2007, 6 discontinued radiotherapy; all were female. Females were also more likely to have a treatment interruption (35% vs 12%, p = .004). Other factors associated with treatment interruption included adjuvant versus neoadjuvant therapy (OR 14.08, 95%CI 1.55-127.87), use of capecitabine versus 5-fluorouracil (OR 75.90, 95%CI 3.33->999), and development of any adverse event (OR 20.66, 95%CI 1.76-242.12). While radiotherapy discontinuation was uncommon in our cohort, for unknown reasons, females were more likely to discontinue or interrupt treatment.

Radiation treatment interruptions greater than one week and low hemoglobin levels (12 g/dL) are predictors of local regional failure after definitive concurrent chemotherapy and intensity-modulated radiation therapy for squamous cell carcinoma of the head and neck

PURPOSE

To determine whether baseline hemoglobin level and radiation treatment interruptions predict for loco-regional failure after intensity-modulated radiation therapy (IMRT) with concurrent chemotherapy for definitive treatment of squamous cell carcinoma of the head and neck (SCCHN).

METHODS

This retrospective review identified 78 consecutive patients treated with definitive concurrent chemoradiation for SCCHN. Patients were treated with IMRT to 70 Gy in 35 daily fractions to the high-dose target volume and 56 Gy to the elective target volume.

RESULTS

Median age of the cohort was 62 (37-81). Median follow-up was 12 months. Tumor sites included: oropharynx (54%), larynx (36%), oral cavity (5%), and hypopharynx (5%). Fifteen of 78 patients (19%) experienced loco-regional failure. These included: 6 primary site failures, 5 regional failures, and 4 failures in both the primary site and regional lymph nodes. All but one failure occurred in the high-dose target volume. Only duration of radiation treatment and baseline hemoglobin levels were significant predictors of local control. Loco-regional failure occurred in 6 of 13 patients (46%) with radiation treatment interruptions (>1 week) versus 9 of 65 patients (14%) completing radiation therapy without interruption (P = 0.0148). Loco-regional failure occurred in 7 of 19 patients (37%) whose pretreatment hemoglobin level was <12 g/dL compared with 8 of 59 patients (14%) with hemoglobin levels > or = 12 (P = 0.042).

CONCLUSION

Overall radiation treatment time and pretreatment hemoglobin level were significant predictors for loco-regional failure after definitive concurrent chemotherapy and IMRT for SCCHN.

Time Factor in Radiotherapy and Chemotherapy for Limited Disease Small-Cell Lung Cancer

The prognostic significance of planned and unplanned gaps in radiotherapy and chemotherapy for limited-disease small-cell lung cancer (LD-SCLC) has been retrospectively evaluated in a series of 245 patients. All of them had cisplatine-based chemotherapy and fractionated radiotherapy. There was substantial heterogeneity in overall radiation treatment time and dose-intensity of chemotherapy attributable mostly to planned and unplanned gaps in therapy. Several variables that potentially may influence survival of the patients after treatment, including duration of treatment gaps, and dose-intensity of chemotherapy and radiotherapy were analyzed using univariate and multivariate Cox regression model. The following variables had significant and independent negative influence on survival in a multivariate model: performance status ZUBROD > 0 (p < 0.0001), metastases to supraclavicular nodes (p = 0.001), dyspnoea according to Borg scale > 2 (p = 0.004) and the average dose intensity of radiotherapy < 80 percent (p = 0.02). An independent association between total dose and survival also has been found. The dose-intensity of chemotherapy did not appear to significantly influence survival. While due to the retrospective character of the present research, this conclusion must be regarded as hypothesis-generating only, we assume that within the range of doses and dose-intensitites used in the present group the preventable gaps in radiotherapy and undue reduction of total radiation dose should be promptly avoided, while gaps in chemotherapy can be deemed acceptable if crucially demanded by the tolerance of treatment.

Causas de interrupção não-programadas da radioterapia

OBJETIVO: Avaliar a ocorrência e as causas de interrupção não-programadas da radioterapia. MATERIAIS E MÉTODOS: Estudo retrospectivo realizado no Serviço de Radioterapia do Hospital Alemão Oswaldo Cruz, na cidade de São Paulo, SP. Os dados foram obtidos dos prontuários dos 560 pacientes submetidos a radioterapia, de 1º de janeiro de 2005 a 31 de dezembro de 2005. Os dados foram analisados pelos testes qui-quadrado e t Student, e os valores de p < 0,05 foram considerados com significância estatística. RESULTADOS: Foram identificados 350 pacientes que interromperam seus tratamentos, o que representou 62,5% do total da amostra. Os motivos foram: manutenção do aparelho (55%), motivos particulares dos pacientes (13%), reações do tratamento ou da associação com quimioterapia (6%), piora clínica (3%), associação de motivos (23%). O intervalo de tempo de interrupção variou de 1 a 24 dias, com média geral de 1,4 dia. Na interrupção de um dia a maior incidência foi ocasionada pela manutenção (84,4%); de dois a cinco dias a interrupção foi causada pela associação de motivos (48,28%). CONCLUSÃO: A causa mais freqüente de interrupção encontrada foi a manutenção preventiva e seu intervalo máximo foi de dois dias.

Interruptions of once-daily thoracic radiotherapy do not correlate with outcomes in limited stage small cell lung cancer: analysis of CALGB phase III trial 9235

PURPOSE

Retrospective data suggests prolonging the time to complete thoracic radiotherapy (TRT) may negatively impact tumor control and survival in limited stage small cell lung cancer (LSCLC). We examined the association between TRT duration and outcomes on a prospective phase III study.

MATERIAL AND METHODS

This review included 267 patients who received protocol TRT on a phase III CALGB LSCLC study assessing the addition of tamoxifen to standard chemo-radiotherapy. TRT, to a planned dose of 50Gy in 2Gy daily fractions, was initiated with the fourth chemotherapy cycle. TRT interruptions were mandated for hematologic toxicity (granulocytes<1000/mm3 or platelets<75,000/mm3) and esophageal toxicity (dysphagia necessitating intravenous hydration).

RESULTS

TRT interruptions > or =3 days occurred in 115 patients (43%), most frequently during the 4th week of TRT, and did not differ between treatment arms. Hematologic toxicity and esophageal toxicity were the most frequent indications for interrupting TRT. Variables including advanced age (>70 years), gender, race, or radiotherapy treatment volume did not predict for TRT interruptions. Overall survival (OS) and local tumor control did not correlate with the administration of TRT interruptions or with TRT duration.

CONCLUSION

Toxicity mandated interruptions of conventional dose, once-daily, TRT may not adversely affect outcomes for patients receiving TRT concurrent with chemotherapy (cycle 4) for LSCLC. The implications for accelerated or high dose TRT regimens are not clear.

Locally advanced stage IV squamous cell carcinoma of the head and neck: impact of pre-radiotherapy hemoglobin level and interruptions during radiotherapy

PURPOSE

Stage IV head and neck cancer patients carry a poor prognosis. Clear understanding of prognostic factors can help to optimize care for the individual patient. This study investigated 11 potential prognostic factors including pre-radiotherapy hemoglobin level and interruptions during radiotherapy for overall survival (OS), metastases-free survival (MFS), and locoregional control (LC) after radiochemotherapy.

METHODS AND MATERIALS

Eleven factors were investigated in 153 patients receiving radiochemotherapy for Stage IV squamous cell head and neck cancer: age, gender, Karnofsky performance score (KPS), tumor site, grading, T stage, N stage, pre-radiotherapy hemoglobin level, surgery, chemotherapy type, and interruptions during radiotherapy>1 week.

RESULTS

On multivariate analysis, improved OS was associated with KPS 90-100 (relative risk [RR], 2.36; 95% confidence interval [CI], 1.20-4.93; p=.012), hemoglobin>or=12 g/dL (RR, 1.88; 95% CI, 1.01-3.53; p=.048), and no radiotherapy interruptions (RR, 2.59; 95% CI, 1.15-5.78; p=.021). Improved LC was significantly associated with lower T stage (RR, 2.17; 95% CI, 1.16-4.63; p=.013), hemoglobin>or=12 g/dL (RR, 4.12; 95% CI, 1.92-9.09; p<.001), surgery (RR, 2.67; 95% CI, 1.28-5.88; p=.008), and no radiotherapy interruptions (RR, 3.32; 95% CI, 1.26-8.79; p=.015). Improved MFS was associated with KPS 90-100 (RR, 3.41; 95% CI, 1.46-8.85; p=.012).

CONCLUSIONS

Significant predictors for outcome in Stage IV head and neck cancer were performance status, stage, surgery, pre-radiotherapy hemoglobin level, and interruptions during radiotherapy>1 week. It appears important to avoid anemia and radiotherapy interruptions to achieve the best treatment results.

Limited-stage small-cell lung cancer: the current status of combined-modality therapy

Limited-stage (LS) small-cell lung cancer (SCLC) remains a therapeutic challenge to medical and radiation oncologists. The treatment of LS-SCLC has evolved significantly over the last two decades with combined-modality therapy now the standard of care. The addition of thoracic radiotherapy (TRT) to standard chemotherapy has led to improvements in long-term survival in this population. However, many questions remain about the optimal way to deliver chemoradiotherapy. In a landmark trial, twice-daily TRT to a dose of 45 Gy increased 5-year survival by 10% compared with once-daily TRT administered to the same dose. This suggests that more intensive TRT regimens may lead to further survival gains, assuming they can be delivered safely in this setting. Strategies currently under investigation include higher total daily doses delivered once daily or novel concurrent boost techniques allowing more intensive treatments over shorter periods of time. Several trials and meta-analyses have evaluated the timing of TRT with chemotherapy, with the weight of evidence suggesting that early and concurrent TRT with chemotherapy is optimal. Novel cytotoxic chemotherapy combinations have failed thus far to provide an advantage over standard etoposide-cisplatin combinations. Prophylactic cranial irradiation in near or complete responders to induction chemoradiotherapy has also been shown to improve long-term survival rates. LS-SCLC has been a model cancer in terms of the potential benefit of combined chemoradiotherapy strategies in improving patient outcomes.

Effects of prolongation of overall treatment time due to unplanned interruptions during radiotherapy of different tumor sites and practical methods for compensation

The prescribed total radiation dose should be administered within a specific time. In daily clinical practice, however, unplanned treatment interruptions resulting in prolongation of the overall treatment time are predictable. The present review evaluated the existing published data regarding the affect of the prolongation of the overall treatment time on the tumor control rate and outcome of patients with head-and-neck, lung, and uterine cervical cancer and other treatment sites. In most studies, including the planned interruption (split-course) schedules, as well as the retrospective studies analyzing the role of overall treatment time, a detrimental effect from the treatment break on the outcome was evident. This is suggestive of the deleterious effect of accelerated repopulation of tumor clonogens. In particular for the cancers of the head and neck for which the evidence is the strongest for such a consequence, even a 1-day interruption resulted in a decrease in the local control rate by 1.4%. Although the increased number of gaps was associated with a negative outcome, the data are contradictory concerning the effect of the number of gaps. The main recommendation is to exert all efforts to retain the planned irradiation schedule; however, existing data have shown that interruptions that effect the programmed time-course for irradiation need to be compensated for. This is to ensure biologic equivalence in treatment efficacy compared with uninterrupted regimens with respect to cancer site and stage. Practical methods for compensation using radiobiologic modeling and their limitations are also discussed.

Thoracic radiation therapy for limited-stage small-cell lung cancer: unanswered questions

The role of thoracic radiation therapy (RT; TRT) is now established in the management of limited-stage small-cell lung cancer (SCLC). There is increasing evidence in the literature in favor of early concurrent chemoradiation therapy, and a gold standard of care for patients with a good performance status is twice-daily TRT (45 Gy in 3 weeks) with concurrent cisplatin/etoposide. Five-year survival rates > 20% can be expected with this combined-modality approach. Although current clinical trials are exploring the efficacy of new chemotherapeutic strategies for the disease, essential questions related to the optimization of TRT remain unanswered. In particular, the optimal RT dose, fractionation, and treatment volume have not been defined. This review highlights the need for well-designed multinational trials aimed at the optimization and standardization of RT for limited-stage SCLC. These trials should integrate translational research studies to investigate the molecular basis of RT resistance and to develop biomarker profiles of prognosis.

Thoracic Radiotherapy for Limited-stage Small-cell Lung Cancer: Controversies and Future developments

Thoracic radiotherapy has an established role in the management of limited-disease small-cell lung cancer (LD SCLC). However, essential questions relating to the optimisation of thoracic radiotherapy remain unanswered, including volume of irradiation, optimal total dose, fractionation, timing and sequencing of radiation. This review highlights the need for well-designed multi-national trials aimed at the optimisation and standardisation of radiotherapy for LD SCLC.

Split-course versus continuous thoracic radiation therapy for limited-stage small-cell lung cancer: final report of a randomized phase III trial

The optimal integration of radiation and chemotherapy for limited-stage small-cell lung cancer (SCLC) remains unclear. This phase III trial was conducted to determine whether chemotherapy plus interdigitating split-course thoracic radiation therapy (RT) improved survival compared with standard-dose continuous thoracic RT. One hundred fourteen patients were randomized to receive 50 Gy thoracic RT delivered in 2.0-Gy fractions given continuously (5 weeks) concurrent with the first 2 cycles of chemotherapy (arm A) or 50 Gy delivered via an interdigitating split course in 2.5-Gy fractions (8 weeks) concurrent with the first 3 cycles of chemotherapy (arm B). During the split-course RT, once-daily radiation was delivered on days 8-17 of each of the first two 21-day cycles and days 8-11 of the third 21-day cycle. All patients received the following chemotherapy: cisplatin/etoposide on cycles 1, 2, and 5 and cyclophosphamide/vincristine/doxorubicin on cycles 3, 4, and 6. Prophylactic cranial irradiation was recommended after a complete response to all therapy. One hundred ten eligible patients were randomized. Grade 3/4 esophagitis was reported in 9% of patients receiving continuous thoracic RT versus 4% of patients receiving split-course RT. Grade 3/4 hematologic toxicity was common in both treatment arms. Complete/partial response was observed in 80% of patients on arm A versus 84% on arm B. Overall survival rates at 5 years were 18% and 17% for arms A and B, respectively. Interdigitating split-course thoracic RT delivered in 2.5-Gy fractions was tolerable in patients with limited-stage SCLC but did not provide a survival advantage.

The Effect of Treatment Interruptions in the Postoperative Irradiation of Breast Cancer

OBJECTIVE

There is much evidence for the detrimental effect of treatment interruptions on tumor control, particularly in head and neck cancer. In order to determine the outcome of the treatment interruptions in postoperative irradiation of breast cancer, 853 female patients treated between 1990 and 1999 inclusive were retrospectively analyzed.

METHODS

Locally advanced breast cancer patients who received neoadjuvant chemotherapy were not included in the study. Five hundred and forty-six patients (64%) treated with mastectomy and 307 patients (36%) with breast-conserving surgery were analyzed. A total dose of 50 Gy (46--54 Gy) was given to the chest wall/breast and regional lymph nodes in 1.8- to 2-Gy daily fractions, 5 times per week. A 14-Gy (10- to 20-Gy) photon or electron boost was given to the tumor bed of the patients with breast-conserving surgery. Unplanned treatment interruptions occurred in 741 (87%) of the patients and the median duration of the gaps was 13 days (1--91 days). A total of 348 patients (41%) had no treatment break or interruptions of 1 week or less, whereas 505 patients (59%) had treatment interruptions of more than 1 week. The locoregional control (LC) and overall survival (OS) rates were estimated with the Kaplan-Meier method. A Cox proportional hazard regression model was used to evaluate the influence of host- and treatment-related factors on LC and OS (age, menopausal status, histological subtype, grade, hormonal receptor status, pT stage, pN stage, type of surgery, adjuvant treatment, number of gaps and duration of gaps).

RESULTS

For all patients LC rates for 5 and 10 years were 95 and 87%, respectively, and OS rates were 78% for 5 years and 62% for 10 years. LC rates for the group of patients with no treatment break or interruptions of 1 week or less, for 5 and 10 years were 94 and 90%, whereas the LC rates for 5 and 10 years were 89 and 86%, for the group of patients with interruptions of more than 1 week (p=0.019). Treatment interruptions of more than 1 week and premenopausal status appeared to be independent adverse prognostic factors in multivariate analyses affecting the LC (p=0.043 and p=0.005, respectively). The OS rates for the patients without treatment interruptions or interruptions of 1 week or less were also significantly better than for the patients with treatment interruptions of more than 1 week (p=0.026) in multivariate analyses.

CONCLUSION

Interruptions more than 1 week during postoperative irradiation of breast cancer adversely affect the treatment outcome.

Effect of overall treatment time on outcomes after concurrent chemoradiation for locally advanced non-small-cell lung carcinoma: analysis of the Radiation Therapy Oncology Group (RTOG) experience

PURPOSE

To determine whether overall treatment time affects outcomes after definitive concurrent chemoradiotherapy for locally advanced non-small-cell lung carcinoma (NSCLC).

METHODS AND MATERIALS

Data were analyzed from 3 prospective Radiation Therapy Oncology Group trials (RTOG 91-06, 92-04, and 94-10) in which immediate concurrent chemoradiation (cisplatin-based) was the primary therapy for good-performance status Stage III (and selected inoperable Stage II) NSCLC. "Short" overall treatment time (per protocol) was defined as completing treatment within 5 days of plan; other patients were considered to have had "prolonged" treatment time (protocol violation); treatment time was also analyzed as a continuous variable in a multivariate model. Actuarial analysis was performed for overall survival, progression-free survival, freedom from local-regional progression, and toxicity.

RESULTS

A total of 474 patients were analyzed. Median follow-up for surviving patients was 6.1 years. Treatment time was delivered per protocol in 387 (82%), whereas 87 patients (18%) had a prolonged treatment time. Long treatment time was significantly associated with severe acute esophagitis. Median survival was slightly better in patients completing treatment on time (19.5 months vs. 14.8 months), but this did not reach statistical significance (p = 0.15) in the univariate analysis. However, in the multivariate analysis of treatment time as a continuous variable, prolonged treatment time was significantly associated with poorer survival (p = 0.02), indicating a 2% increase in the risk of death for each day of prolongation in therapy. Histology (squamous fared worse) and performance status were also significant in the multivariate model.

CONCLUSIONS

This retrospective analysis demonstrates a correlation between prolonged overall radiotherapy treatment time and survival in patients with locally advanced NSCLC, even when concurrent chemotherapy is used. Further study of novel radiation-chemotherapy dose/fractionation regimens is warranted.

[Delays and treatment interruptions: difficulties in administering radiotherapy in an ideal time-period]

Prescribed total radiation dose should be administered within in a specific time-frame and delays in commencing treatment and/or unplanned interruptions in radiation delivery are unacceptable because, in certain cancer sites, treatment-time prolongation can have a deleterious effect on local tumour control, and on patient outcomes. The present review evaluated the causes of initial treatment delays as well as interruptions in the scheduled radiotherapy. The literature search highlighted a significant concern in avoiding treatment-time prolongation in head and neck, cervix, breast and lung cancer. Among the causes involved in delay in radiotherapy commencement factors such as waiting lists, lack of material and human resources, and an increase complexity in planning, simulation and verification are highlighted. Most authors recommend radiotherapy commencement as soon as possible in radical (exclusive irradiation with active tumour present) and palliative situations with a maximum delay of no more than 6 to 8 weeks in the case of adjuvant radiotherapy (post-resection) programs. Interruptions during the course of treatment include: planned unit maintenance and servicing, acute patient toxicity or unexpected malfunction of linear accelerators; this last feature has the most deleterious effect on patients as well as radiotherapy practitioners. Interruptions that impact on the programmed time-course for radiotherapy needs to be compensated-for so as assure the biological equivalence in treatment efficacy with respect to cancer site and stage.

Impaired diffusion capacity predicts for decreased treatment tolerance and survival in limited stage small cell lung cancer patients treated with concurrent chemoradiation

PURPOSE

To determine if stratification of limited stage small cell lung cancer (LSCLC) patients by pre-treatment pulmonary function test (PFT) prognostic indicators predicts for treatment-related toxicity risks and survival following concurrent chemoradiation.

MATERIALS AND METHODS

From 1989 to 1999, 215 LSCLC patients received six cycles of alternating cyclophosphamide/doxorubicin/vincristine and etoposide/cisplatin (EP). Thoracic radiation (RT) was initiated only with EP and at cycle 2 or 3. RT dose was: 40 Gy/15 fractions/3 weeks or 50 Gy/25 fractions/5 weeks. RT fields encompassed gross and suspected microscopic disease with a 2 cm margin. Pre-treatment PFT values analyzed included forced expiratory volume in 1s (FEV1) (in liter and as % predicted) and diffusion capacity for carbon monoxide (DLCO) (as % predicted). The "marker" for toxicity during concurrent chemoradiation was the duration of any RT breaks initiated for severe hematologic or locoregional symptomatology. Patient outcomes were analyzed for associations between recognized PFT cut-offs (FEV1 <2l, > or =2l; FEV1 <60%, > or =60% predicted; DLCO <60%, > or =60% predicted), toxicity rates, and survival.

RESULTS

For the whole study cohort, median, 2- and 5-year overall survivals were: 14.7 months, 22.7 and 7.2%, respectively. Fifty-six patients (26%) required treatment breaks due to toxicity. FEV1 and DLCO results were available for 96 (45%) and 86 (40%) patients, respectively. Two thirds of FEV1s measured were <2l. On statistical analysis, the incidence of toxicity-related interruptions was significant for DLCO<60% (P=0.043), suggestive for FEV1<2l (P=0.1) and non-significant for FEV1<60%. Patients with simultaneous DLCO<60% and FEV1<2l showed a trend toward increase toxicity risk (P=0.1). For selected PFT measures, median overall survivals were: 12.7 months versus 14.8 months for DLCO<60% versus > or =60%; 13.4 months versus 17.7 months for FEV1<2l versus > or =2l; 15.4 months versus 19.9 months for DLCO<60% + FEV1<2l versus DLCO> or =60% + FEV1> or =2l. Although absolute differences favored all patients with PFT values above the prognostic cut-offs, differences were not statistically significant on this analysis. Patients with both a treatment break and a DLCO<60% had the poorest median survival of all patient subsets, at 11.4 months (P=0.09).

CONCLUSIONS

Impaired DLCO (i.e. <60%) is a novel predictor of increased treatment-related toxicity leading to interruptions. The present study suggests a probable role for DLCO and FEV1 (in l) as prognostic factors for predicting survival but larger patient samples are required for confirmation. Patients with impaired DLCOs experiencing treatment interruptions have the poorest survival. Assessment of pre-treatment PFTs contributes to determining optimal management strategies for LSCLC patients receiving definitive chemoradiation.

Shifting from hypofractionated to "conventionally" fractionated thoracic radiotherapy: a single institution's 10-year experience in the management of limited-stage small-cell lung cancer using concurrent chemoradiation

PURPOSE

To perform a retrospective review of a single institution's 10-year experience in treating limited-stage small-cell lung cancer (LS-SCLC) with a concurrent chemoradiation regimen modeled after the experimental arm of a randomized National Cancer Institute of Canada trial in which hypofractionated radiotherapy started with cycle 2 of chemotherapy. We then looked at the impact on patient outcomes of changing the RT during the course of the decade to a "conventionally" (2 Gy) fractionated regimen, with a focus on toxicity and survival rates.

METHODS AND MATERIALS

Between 1989 and 1999, 215 LS-SCLC patients received six cycles of chemotherapy consisting of cyclophosphamide, doxorubicin, and vincristine alternating with etoposide and cisplatin every 3 weeks. Thoracic RT was administered concurrently with etoposide and cisplatin (at cycle 2 or 3) only and consisted of either 40 Gy in 15 fractions for 3 weeks or 50 Gy in 25 fractions for 5 weeks. RT fields encompassed gross and suspected microscopic disease with 2-cm margins. Prophylactic cranial irradiation (PCI) was offered to complete responders according to clinician preference. RT interruption during concurrent chemoradiation was used as the "marker" for treatment toxicity. The analysis compared the RT schedules for differences in toxicity, survival, and recurrence patterns.

RESULTS

The overall survival rate for 215 patients at 2 and 5 years was 22.7% and 7.2%, respectively, with a median survival of 14.7 months. Thoracic RT consisted of 40 Gy in 3 weeks for 122 patients (57%) and 50 Gy in 5 weeks for 92 patients (43%). PCI was administered to 21 (44%) and 47 (56%) patients receiving 40 Gy and 50 Gy, respectively. The patient- and treatment-related variables were comparable between the two cohorts treated with the different RT prescriptions. RT interruptions during concurrent chemoradiation were recorded in 56 cases (26%), with a median duration of 5 days (range 1-18). No differences in treatment-related toxicity rates were demonstrated between the two dose cohorts (p = 0.35). The overall and disease-free survival rates (patients stratified by PCI use) at 5 years for the 40- and 50-Gy schedules were 14.3% and 12.0% (p = 0.71) and 20.7% and 22.2% (p = 0.76), respectively. Sites of first failure were recorded in 132 patients (61%). Comparing the 40-Gy and 50-Gy cohorts, the rate of any first relapse was 40% vs. 42% and the chest as the first relapse site was 34% vs. 45% (patients stratified by PCI use), respectively. The brain failure rate reflected PCI use and was not related to the thoracic RT schedule.

CONCLUSION

Changing from a hypofractionated to a conventionally fractionated RT thoracic prescription did not alter outcomes because the survival, thoracic control, and toxicity rates were statistically similar. This suggests that the hypofractionated schedule remains practicable and should be considered in the setting of randomized clinical trials. In view of the benefits that accelerated schedules provide for both patients and cost containment, clinicians may opt to use this tolerable regimen in managing LS-SCLC. Regarding the future development of novel chemoradiation programs, the most critical factor in ensuring improved outcomes for LS-SCLC may be limiting the duration of RT and overall treatment time.

Neuropsychological effects of treatments for adults with cancer: a meta-analysis and review of the literature

A meta-analysis was conducted to evaluate possible neuropsychological effects of treatments for cancer in adults. A search revealed 30 studies, encompassing 29 eligible samples, and leading to inclusion of a total of 838 patients and control participants. A total of 173 effect sizes (Cohen's d) were extracted across 7 cognitive domains and as assessed in the literature via 3 methods of comparison (post-treatment compared with normative data, controls, or baseline performance). Statistically significant negative effect sizes were found consistently across both normative and control methods of comparison for executive function, verbal memory, and motor function. The largest effects were for executive function and verbal memory normative comparisons (-.93 and -.91, respectively). When limiting the sample of studies in the analyses to only those with relatively "less severe" diagnoses and treatments, the effects remained. While these results point toward some specific cognitive effects of systemic cancer therapies in general, no clear clinical implications can yet be drawn from these results. More research is needed to clarify which treatments may produce cognitive decrements, the size of those effects, and their duration, while ruling out a wide variety of possible mediating or moderating variables.

Continued cigarette smoking by patients receiving concurrent chemoradiotherapy for limited-stage small-cell lung cancer is associated with decreased survival

PURPOSE

To determine the impact of continued smoking by patients receiving chemotherapy (CHT) and radiotherapy (RT) for limited-stage small-cell lung cancer (LSCLC) on toxicity and survival.

PATIENTS AND METHODS

A retrospective review was carried out on 215 patients with LSCLC treated between 1989 and 1999. Treatment consisted of six cycles of alternating cyclophosphamide, doxorubicin, vincristine and etoposide, cisplatin (EP). Thoracic RT was concurrent with EP (cycle 2 or 3) only. Patients were known smokers, with their smoking status recorded at the start of chemoradiotherapy (CHT/RT). RT interruption during concurrent CHT/RT was used as the marker for treatment toxicity.

RESULTS

Of 215 patients, smoking status was recorded for 186 patients (86.5%), with 79 (42%) continuing to smoke and 107 (58%) abstaining during CHT/RT. RT interruptions were recorded in 38 patients (20.5%), with a median duration of 5 days (range, 1 to 18 days). Median survival for former smokers was greater than for continuing smokers (18 v 13.6 months), with 5-year actuarial overall survival of 8.9% versus 4%, respectively (log-rank P =.0017). Proportion of noncancer deaths was comparable between the two cohorts. Continuing smokers did not have a greater incidence of toxicity-related treatment breaks (P =.49), but those who continued to smoke and also experienced a treatment break had the poorest overall survival (median, 13.4 months; log-rank P =.0014).

CONCLUSION

LSCLC patients who continue to smoke during CHT/RT have poorer survival rates than those who do not. Smoking did not have an impact on the rate of treatment interruptions attributed to toxicity.

Thoracic radiotherapy for limited-stage small cell lung cancer: issues of timing, volumes, dose, and fractionation

Although meta-analysis of randomized trials comparing chemotherapy alone versus chemotherapy plus thoracic irradiation demonstrated that thoracic radiotherapy reduced mortality by 14%, this analysis probably underestimates the effect of optimally delivered thoracic irradiation integrated with appropriate chemotherapy. However, there remains much debate as to the optimal timing of the radiotherapy and the radiotherapy volume, dose, and fractionation. Theoretically, early use of radiotherapy should reduce the probability of chemotherapy and radiation resistance, accelerated repopulation, and metastatic events. Deferred or sequential radiotherapy potentially allows smaller radiotherapy fields. Of the seven randomized controlled trials examining timing, only those with early chemoradiation have 5-year survival rates in excess of 20%. The "chemoradiation package" can be defined as the time from the start of chemotherapy until the completion of radiotherapy. The best median survival and long-term survival rates have been observed in trials with a chemoradiation package time of less than 6 weeks. Protocols combining chemotherapy and radiotherapy must respect radiobiologic principles concerning the time factor derived from radiotherapy fractionation studies.