A phase II study of paclitaxel + etoposide + cisplatin + concurrent radiation therapy for previously untreated limited stage small cell lung cancer (E2596): a trial of the Eastern Cooperative Oncology Group

Population Survival Kinetics Derived from Clinical Trials of Potentially Curable Lung Cancers

Using digitized data from progression-free survival (PFS) and overall survival Kaplan-Meier curves, one can assess population survival kinetics through exponential decay nonlinear regression analyses. To demonstrate their utility, we analyzed PFS curves from published curative-intent trials of non-small cell lung cancer (NSCLC) adjuvant chemotherapy, adjuvant osimertinib in resected EGFR-mutant NSCLC (ADAURA trial), chemoradiotherapy for inoperable NSCLC, and limited small cell lung cancer (SCLC). These analyses permit assessment of log-linear curve shape and estimation of the proportion of patients cured, PFS half-lives for subpopulations destined to eventually relapse, and probability of eventual relapse in patients remaining progression-free at different time points. The proportion of patients potentially cured was 41% for adjuvant controls, 58% with adjuvant chemotherapy, 17% for ADAURA controls, not assessable with adjuvant osimertinib, 15% with chemoradiotherapy, and 12% for SCLC. Median PFS half-life for relapsing subpopulations was 11.9 months for adjuvant controls, 17.4 months with adjuvant chemotherapy, 24.4 months for ADAURA controls, not assessable with osimertinib, 9.3 months with chemoradiotherapy, and 10.7 months for SCLC. For those remaining relapse-free at 2 and 5 years, the cure probability was 74%/96% for adjuvant controls, 77%/93% with adjuvant chemotherapy, 51%/94% with chemoradiation, and 39%/87% with limited SCLC. Relatively easy population kinetic analyses add useful information.

Chemotherapy combined with bevacizumab for small cell lung cancer with brain metastases: A case report

BACKGROUND

Small cell lung cancer (SCLC) is a common and aggressive subtype of lung cancer. It is characterized by rapid growth and a high mortality rate. Approximately 10% of patients with SCLC present with brain metastases at the time of diagnosis, which is associated with a median survival of 5 mo. This study aimed to summarize the effect of bevacizumab on the progression-free survival (PFS) and overall survival of patients with brain metastasis of SCLC.

CASE SUMMARY

A 62-year-old man was referred to our hospital in February 2023 because of dizziness and numbness of the right lower extremity without headache or fever for more than four weeks. The patient was diagnosed with limited-stage SCLC. He received 8 cycles of chemotherapy combined with maintenance bevacizumab therapy and achieved a PFS of over 7 mo.

CONCLUSION

The combination of bevacizumab and irinotecan effectively alleviated brain metastasis in SCLC and prolonged PFS.

Radiation and Systemic Therapy for Limited-Stage Small-Cell Lung Cancer

Progress in the overall treatment of small-cell lung cancer (SCLC) has moved at a slower pace than non-small-cell lung cancer. In fact, the standard treatment regimen for limited stage SCLC has not appreciably shifted in more than 20 years, consisting of four to six cycles of cisplatin and etoposide chemotherapy concurrent with thoracic radiotherapy (TRT) followed by prophylactic cranial irradiation (PCI) for responsive disease. Nevertheless, long-term outcomes have improved with median survival approaching 25-30 months, and approximately one third of patients now survive 5 years. This is likely attributable in part to improvements in staging, including use of brain magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography imaging, advances in radiation treatment planning, and supportive care. The CONVERT and CALGB 30610 phase III trials failed to demonstrate a survival advantage for high-dose, once-daily TRT compared with standard 45 Gy twice-daily TRT, although high-dose, once-daily TRT remains common in practice. A phase III comparison of high-dose 60 Gy twice-daily TRT versus 45 Gy twice-daily TRT aims to confirm the provocative outcomes reported with 60 Gy twice daily in the phase II setting. Efforts over time have shifted from intensifying PCI, to attempting to reduce treatment-related neurotoxicity, to more recently questioning whether careful magnetic resonance imaging surveillance may obviate the routine need for PCI. The addition of immunotherapy has resulted in mixed success in extensive-stage SCLC with modest benefit observed with programmed death-ligand 1 inhibitors, and several ongoing trials assess programmed death-ligand 1 inhibition concurrent or adjuvant to chemoradiotherapy in limited-stage SCLC. Major advances in future treatment will likely depend on a better understanding and exploiting of molecular characteristics of SCLC with increasing personalization of therapy.

Thoracic radiotherapy in small cell lung cancer-a narrative review

Small-cell lung cancer (SCLC) represents 10–15% of all lung cancers and has a poor prognosis. Thoracic radiotherapy plays a central role in current SCLC management. Concurrent chemoradiotherapy (CTRT) is the standard of care for localised disease (stage I−III, limited-stage, LS). Definitive thoracic radiotherapy may be offered in metastatic patients (stage IV, extensive stage, ES-SCLC) after chemotherapy. For LS-SCLC, the gold standard is early accelerated hyperfractionated twice-daily CTRT (4 cycles of cisplatin etoposide, starting with the first or second chemotherapy cycle). Modern radiation techniques should be used with involved-field radiotherapy based on baseline CT and PET/CT scans. In ES-SCLC, thoracic radiotherapy should be discussed in cases of initial bulky mediastinal disease/residual thoracic disease not progressing after induction chemotherapy. This strategy was however not assessed in recent trials establishing chemo-immunotherapy as the standard first line treatment in ES-SCLC. Future developments include technical radiotherapy advances and the incorporation of new drugs. Thoracic irradiation is delivered more precisely given technical developments (IMRT, image-guided radiotherapy, stereotactic radiotherapy), reducing the risks of severe adverse events. Stereotactic ablative radiotherapy may be discussed in rare early stage (T1 to 2, N0) inoperable patients. A number of current clinical trials are investigating immunoradiotherapy. In this review, we highlight the current role of thoracic radiotherapy and describe ongoing research in the integration of biological surrogate markers, advanced radiotherapy technologies and novel drugs in SCLC patients.

Radiation Therapy for Small Cell Lung Cancer: An ASTRO Clinical Practice Guideline

PURPOSE

Several sentinel phase III randomized trials have recently been published challenging traditional radiation therapy (RT) practices for small cell lung cancer (SCLC). This American Society for Radiation Oncology guideline reviews the evidence for thoracic RT and prophylactic cranial irradiation (PCI) for both limited-stage (LS) and extensive-stage (ES) SCLC.

METHODS

The American Society for Radiation Oncology convened a task force to address 4 key questions focused on indications, dose fractionation, techniques and timing of thoracic RT for LS-SCLC, the role of stereotactic body radiation therapy (SBRT) compared with conventional RT in stage I or II node negative SCLC, PCI for LS-SCLC and ES-SCLC, and thoracic consolidation for ES-SCLC. Recommendations were based on a systematic literature review and created using a consensus-building methodology and system for grading evidence quality and recommendation strength.

RESULTS

The task force strongly recommends definitive thoracic RT administered once or twice daily early in the course of treatment for LS-SCLC. Adjuvant RT is conditionally recommended in surgically resected patients with positive margins or nodal metastases. Involved field RT delivered using conformal advanced treatment modalities to postchemotherapy volumes is also strongly recommended. For patients with stage I or II node negative disease, SBRT or conventional fractionation is strongly recommended, and chemotherapy should be delivered before or after SBRT. In LS-SCLC, PCI is strongly recommended for stage II or III patients who responded to chemoradiation, conditionally not recommended for stage I patients, and should be a shared decision for patients at higher risk of neurocognitive toxicities. In ES-SCLC, radiation oncologist consultation for consideration of PCI versus magnetic resonance surveillance is strongly recommended. Lastly, the use of thoracic RT is strongly recommended in select patients with ES-SCLC after chemotherapy treatment, including a conditional recommendation in those responding to chemotherapy and immunotherapy.

CONCLUSIONS

RT plays a vital role in both LS-SCLC and ES-SCLC. These guidelines inform best clinical practices for local therapy in SCLC.

Anti-angiogenesis treatment in a patient with appendix metastasis of small cell lung cancer: A case report

RATIONALE

Small-cell lung cancer (SCLC) is a common pathological type of lung cancer, but appendiceal metastasis of SCLC was rare. At present, clinical studies on the maintenance therapy of SCLC have not reached a significant conclusion.

PATIENT CONCERNS

We reported on a 52-year-old man who diagnosed as extensive stage SCLC with abdominal pain for 2 months, aggravated for 2 days.

DIAGNOSES

The patient was diagnosed with extensive-stage SCLC, relapsed with appendix metastasis after treatment by emergency abdominal surgery.

INTERVENTIONS

The patient received systemic treatments, including surgery, bevacizumab in combination with chemotherapy and bevacizumab alone was continued as maintenance therapy.

OUTCOMES

The patient had an overall survival would more than 23 months, and he gained another 8 months of progression-free survival after first-line radiochemotherapy.

LESSONS

Although SCLC appendix metastasis is rare, continuous anti-angiogenic therapy combined with bevacizumab maintenance therapy after surgical treatment can prolong survival.

A pooled analysis of individual patient data from National Clinical Trials Network clinical trials of concurrent chemoradiotherapy for limited-stage small cell lung cancer in elderly patients versus younger patients

BACKGROUND

Platinum and etoposide with thoracic radiation followed by prophylactic cranial irradiation constitute the standard treatment for limited-stage small cell lung cancer (LS-SCLC). Many patients with LS-SCLC are elderly with comorbidities.

METHODS

Individual patient data were collected from 11 phase 2 or 3 trials for LS-SCLC conducted by the National Clinical Trials Network and activated from 1990 to 2010. The primary endpoint was overall survival (OS); the secondary endpoints were progression-free survival (PFS), the rate of severe adverse events, and off-treatment reasons. The outcomes were compared for patients 70 years old or older (elderly patients) and patients younger than 70 years (younger patients).

RESULTS

Individual patient data from 1049 younger patients (81%) and 254 elderly patients (19%) were analyzed. In the multivariate model, elderly patients, in comparison with younger patients, had worse OS (hazard ratio [HR], 1.38; 95% confidence interval [CI], 1.18-1.63; median OS for elderly patients, 17.8 months; OS for younger patients, 23.5 months) and worse PFS (HR, 1.19; 95% CI, 1.03-1.39; median PFS for elderly patients, 10.6 months; median PFS for younger patients, 12.3 months). Elderly patients, in comparison with younger patients, experienced more grade 5 adverse events (8% vs 3%; P < .01) and more grade 3 or higher dyspnea (11% vs 7%; P = .03) but less grade 3 or higher esophagitis/dysphagia (14% vs 19%; P = .04) and less grade 3 or higher vomiting (11% vs 17%; P = .01). Elderly patients completed treatment less often, discontinued treatment because of adverse events and patient refusal more frequently, and died during treatment more frequently.

CONCLUSIONS

Elderly patients with LS-SCLC have worse PFS and OS and more difficulty in tolerating therapy. Future trials should incorporate assessments of elderly patients, novel monitoring of adverse events, and more tolerable radiation and systemic therapies.

[Radiotherapy for small cell lung carcinoma]

Radiotherapy for small cell lung carcinoma has known significant improvements over the past 10 years especially through routine use of PET-CT in the initial work-up and contouring before treatment. Prophylactic cranial irradiation remains a standard of care for locally advanced disease and is a subject of controversy for metastatic disease. A new indication for thoracic radiotherapy may soon arise for metastatic disease, still confirmation studies are ongoing.

Quantitative analysis of tumor shrinkage due to chemotherapy and its implication for radiation treatment planning in limited-stage small-cell lung cancer

Background

The optimal timing of chemoradiotherapy in limited-stage small-cell lung cancer (LS-SCLC) hasn’t been established, although evidence from studies supported that patients can benefit from early radiation therapy. The purpose of this study was to quantify tumor shrinkage in response to induction chemotherapy (IC), evaluate the impact of tumor shrinkage on radiation dosimetric parameters and determine its implication for the timing of radiation therapy for patients with LS-SCLC.

Methods

Twenty patients with LS-SCLC who were treated with IC followed by concomitant radiation therapy were investigated retrospectively. Ten patients received 1 cycle of IC, and 10 patients received 2 cycles of IC. Pre-IC CT imaging was coregistered with a simulation CT, and virtual radiation plans were created for pre- and post-IC thoracic disease in each case. The changes in the gross target volume (GTV), planning target volume (PTV) and dosimetric factors associated with the lungs, esophagus and heart were analyzed.

Results

The mean GTV and PTV for all of the patients decreased by 60.9% and 40.2%, respectively, which resulted in a significant reduction in the radiation exposure to the lungs, esophagus and heart. Changes in the PTV and radiation exposure of normal tissue were not significantly affected by the number of chemotherapy cycles delivered, although patients who received 2 cycles of IC had a greater decrease in GTV than those who received only 1 cycle of IC (69.6% vs. 52.1%, p = 0.273).

Conclusions

Our data showed that targeting the tumor post-IC may reduce the radiation dose to normal tissue in patients with LS-SCLC. However, the benefit to the normal tissue was not increased by an additional cycle of IC. These findings suggest that the first cycle of chemotherapy is very important for tumor shrinkage and that initiating thoracic radiation therapy at the second cycle of chemotherapy may be a reasonable strategy for timing of radiation therapy in LS-SCLC treatment.

Radiation/paclitaxel treatment of p53-abnormal non-small cell lung cancer xenograft tumor and associated mechanism

BACKGROUND

Mutations in key tumor suppressor genes such as tumor protein 53 (TP53) and phosphatase and tensin homolog deleted on chromosome ten (PTEN) are the main genetic alterations in cancers. TP53 mutations have been found in most patients with non-small cell lung cancer (NSCLC), whereas PTEN mutations are rarely found in lung cancer, though most NSCLCs lack PTEN protein synthesis. However, the signaling involved in radio- and chemotherapy of NSCLC with wild-type PTEN and nonfunctional p53 is not clearly understood.

METHODS

In this study, we established a xenograft tumor model with H358 NSCLC cells expressing wild-type PTEN, but nonfunctional p53. Protein expression and phosphorylation of PTEN and its downstream signal molecules in NSCLC tissues were detected by Western blot.

RESULTS

We demonstrated that radiation and paclitaxel alone inhibited tumor growth, but a combined therapy of radiation and paclitaxel was more effective in inhibiting NSCLC tumor growth. Interestingly, both radiation and paclitaxel significantly increased PTEN protein expression and phosphorylation. Further identification of the affected PTEN downstream molecules showed that Akt phosphorylation at Ser(473) and Thr(308) residues was significantly decreased, whereas Bax and cleaved caspase-3 levels were significantly increased in tumor tissues treated with both radiation and paclitaxel. The combined treatment was more effective than either treatment alone in regulating the studied molecules. We also found that paclitaxel, but not radiation, inhibited phosphoinositide 3-kinase (PI3K) activity.

CONCLUSIONS

Our study suggested that a PTEN-PI3K-Akt-Bax signaling cascade is involved in the therapeutic effect of combined radiation/paclitaxel treatment in NSCLC without p53 expression. Our study also suggested that PTEN is an ideal target in tumors with wild-type PTEN and a lack of functional p53.

Limited-stage small cell lung cancer: current chemoradiotherapy treatment paradigms

In the U.S., the prevalence of small cell lung cancer (SCLC) is declining, probably reflecting the decreasing prevalence of tobacco use. However, a significant number of patients will receive a diagnosis of SCLC, and approximately 40% of patients with SCLC will have limited-stage (LS) disease, which is potentially curable with the combination of chemotherapy and radiation therapy. The standard therapy for LS-SCLC is concurrent chemoradiotherapy, and the 5-year survival rate observed in clinical trials is approximately 25%. The standard chemotherapy remains cisplatin and etoposide, but carboplatin is frequently used in patients who cannot tolerate or have a contraindication to cisplatin. Substantial improvements in survival have been made through improvements in radiation therapy. Concurrent chemoradiotherapy is the preferred therapy for patients who are appropriate candidates. The optimal timing of concurrent chemoradiotherapy is during the first or second cycle, based on data from meta-analyses. The optimal radiation schedule and dose remain topics of debate, but 1.5 Gy twice daily to a total of 45 Gy and 1.8-2.0 Gy daily to a total dose of 60-70 Gy are commonly used treatments. For patients who obtain a near complete or complete response, prophylactic cranial radiation reduces the incidence of brain metastases and improves overall survival. The ongoing Radiation Therapy Oncology Group and Cancer and Leukemia Group B and the European and Canadian phase III trials will investigate different radiation treatment paradigms for patients with LS-SCLC, and completion of these trials is critical.