Additional radiation boost to whole brain radiation therapy may improve the survival of patients with brain metastases in small cell lung cancer

A dosimetric comparison of non-coplanar volumetric modulated arc therapy and non-coplanar fixed field intensity modulated radiation therapy in hippocampus-avoidance whole-brain radiation therapy with a simultaneous integrated boost for brain metastases

Objective

The aim of this study was to investigate the dosimetric differences between non-coplanar volumetric modulated arc therapy (VMAT) and non-coplanar fixed-field intensity-modulated radiotherapy (IMRT) in hippocampus-avoidance whole-brain radiation therapy with a simultaneous integrated boost (HA-WBRT+SIB) for brain metastases using the Monaco treatment planning system (TPS).

Method

A total of 22 patients with brain metastases were retrospectively enrolled. Two radiotherapy treatment plans were designed for each patient: non-coplanar VMAT and non-coplanar fixed field IMRT. The dose distribution of targets and organs at risk (OAR), the number of monitor units (MUs), and pre-treatment plan verification were compared between the two plans while meeting the prescribed dose requirements of the target volume.

Results

There were no significant differences in V50, V55, Dmax, heterogeneity index (HI) and conformity index (CI) of target PGTV between the two plans (p>0.05). For PTV-brain-SIB, there was no significant difference in D98% between IMRT and VMAT (p=0.103). VMAT significantly improved the V30 of PTV-brain-SIB (p<0.001), decreased HI (p=0.003), and increased CI (p<0.001). There were no significant differences in the Dmax to the brain stem, left and right lens, optic chiasm, pituitary gland, and left and right hippocampus between the two plans (p>0.05). Compared with IMRT, VMAT significantly reduced the Dmax to the left and right eyes (p<0.001) and significantly increased the Dmax to the right inner ear (p=0.010). There was no significant difference in the Dmax to the left inner ear between VMAT and IMRT (p=0.458). Compared with IMRT, VMAT significantly reduced the Dmax to the left optic nerve (p=0.006), but significantly increased the Dmax to the right optic nerve (p=0.001). There was no significant difference in the Dmax to the left and right hippocampus between VMAT and IMRT (p>0.05), but VMAT significantly increased the D100% (p<0.05) compared with IMRT. Compared with VMAT, IMRT significantly reduced the MU (p<0.001) but VMAT has a higher treatment efficiency than IMRT, with an average reduction of 41 seconds (294.1 ± 16.4 s for VMAT, 335.8 ± 34.9 s for IMRT, p<0.001). Under the conditions of 3%/2 mm, and 2%/2 mm, the gamma passing rate of the IMRT QA was improved compared to VMAT, with an average increase of 0.6%, p=0.013, and 1.7%, p<0.001, respectively.

Conclusion

Both non-coplanar VMAT and non-coplanar fixed field IMRT based on the Monaco TPS produce clinically acceptable results for HA-WBRT+SIB in patients with brain metastases. Compared with IMRT, VMAT has better dose distribution in the target volume and treatment efficiency, but IMRT can better protect the hippocampus and reduce the number of MUs.

Association between PET-CT accumulation in the hypothalamic/pituitary regions and neuron-specific enolase/primary tumor in limited-stage small cell lung cancer: a case-controlled retrospective study

BACKGROUND

Research on the relationship between neuron-specific enolase (NSE) levels and normal organs, particularly the central nervous system, in small cell lung cancer is limited. Therefore, this study aimed to investigate the relationship between positron emission tomography-computed tomography (PET-CT) accumulation at hypothalamic/pituitary regions, tumor activity, and NSE level in limited-stage small cell lung cancer. We retrospectively analyzed patients who were diagnosed with limited-stage small cell lung cancer at Tokyo Medical University Hospital between July 1, 2019, and May 31, 2023, and were treated with chemoradiotherapy or radiotherapy. Leukocytes, erythrocytes, hemoglobin, platelets, total protein, albumin, NSE, and carcinoembryonic antigen were measured in blood samples obtained before treatment initiation. The maximum standardized uptake value (SUVmax), volume, and total lesion glycolysis (TLG) of each hypothalamic /pituitary region, primary tumor, and lymph node metastases were extracted from PET-CT images. The total tumor volume (primary tumor volume plus lymph node metastases volume) and total TLG (primary tumor TLG plus lymph node metastases TLG) were calculated.

RESULTS

This study included 19 patients (mean age, 70.1 ± 8.8 years; 13 men and 6 women); the pathology in all patients was small cell lung cancer. Patients were classified into two groups according to the NSE reference value (16.3 ng/mL): six patients having NSE level below the reference value and 13 having NSE level above the reference value. The SUVmax in the hypothalamic/pituitary region was 2.95 in the NSE < 16.3 ng/mL group and 4.10 in the NSE > 16.3 ng/mL group, with a statistically significant difference (p = 0.03). The total tumor volume was 17.8 mL in the NSE < 16.3 ng/mL group and 98.9 mL in the NSE > 16.3 ng/mL group, with a statistically significant difference (p < 0.01). A correlation coefficient of r = 0.458 (p = 0.0486) was observed between SUVmax in the hypothalamus/pituitary and NSE level. A correlation coefficient of r = 0.647 (p < 0.01) was also observed between total tumor volume and NSE level. Finally, a correlation coefficient of r = 0.53 (p = 0.01) was observed between hypothalamic/pituitary TLG and primary tumor TLG.

CONCLUSIONS

The findings demonstrated a correlation between hypothalamic/pituitary activity and tumor activity, suggesting the prognostic significance of NSE.

Adding simultaneous integrated boost to whole brain radiation therapy improved intracranial tumour control and minimize radiation-induced brain injury risk for the treatment of brain metastases

BACKGROUND

Brain metastases (BMs) are the most frequent intracranial tumours associated with poor clinical outcomes. Radiotherapy is essential in the treatment of these tumours, although the optimal radiation strategy remains controversial. The present study aimed to assess whether whole brain radiation therapy with a simultaneous integrated boost (WBRT + SIB) provides any therapeutic benefit over WBRT alone.

METHODS

We included and retrospectively analysed 82 patients who received WBRT + SIB and 83 who received WBRT alone between January 2012 and June 2021. Intracranial progression-free survival (PFS), local tumour control (LTC), overall survival (OS), and toxicity were compared between the groups.

RESULTS

Compared to WBRT alone, WBRT + SIB improved intracranial LTC and PFS, especially in the lung cancer subgroup. Patients with high graded prognostic assessment score or well-controlled extracranial disease receiving WBRT + SIB had improved intracranial PFS and LTC. Moreover, WBRT + SIB also improved the long-term intracranial tumour control of small cell lung cancer patients. When evaluating toxicity, we found that WBRT + SIB might slightly increase the risk of radiation-induced brain injury, and that the risk increased with increasing dosage. However, low-dose WBRT + SIB had a tolerable radiation-induced brain injury risk, which was lower than that in the high-dose group, while it was comparable to that in the WBRT group.

CONCLUSIONS

WBRT + SIB can be an efficient therapeutic option for patients with BMs, and is associated with improved intracranial LTC and PFS. Furthermore, low-dose WBRT + SIB (biologically effective dose [BED] ≤ 56 Gy) was recommended, based on the acceptable risk of radiation-induced brain injury and satisfactory tumour control.

TRIAL REGISTRATION

Retrospectively registered.

Low radiotherapy dose is suitable for brain metastases in SCLC compared with high dose

Objective

This study was designed to evaluate the suitable radiotherapy dose in SCLC patients with BM.

Methods

A retrospective analysis was performed among 121 patients on the prognosis of BM of SCLC who were admitted to our hospital from 2013 to 2023. They all received first line chemotherapy. 80 patients of them received TRT after chemotherapy. The Chi square method was used to compare the categorical data. Univariate survival analysis was estimated by Kaplan Meier method and the logrank was used to compare survival curves between groups. A multivariate prognostic analysis was made by the Cox proportional hazard model. The iOS and iLC of two groups of low dose and high dose were analyzed after propensity score matching (PSM).

Results

In all the patients, the median follow-up time was 18.6 months (range 6.30~85.7), the 2-year iOS and iLC rates were 15.4% and 70.3%, respectively, and cerebral necrosis occurred in 2 patients. In univariate analysis related to iOS, extracranial disease control (p=0.023), higher DS-GPA (≥2) (p=0.016), immunotherapy (p=0.049), low-dose(p=0.030), and WBRT+SIB (p=0.009) were significantly associated with an increase in survival rate. After PSM, the 2-year iOS of low dose (n=49) was significantly higher than that of high dose (n=49) (P=0.025), while the 2-year iLC was not significantly improved (P=0.267). In DS-GPA < 2 subgroup, the iOS of low dose group was significantly higher than that of high dose group (p=0.019). In the DS-GPA ≥ 2 subgroup, the 2-year iLC of the low dose group was significantly inferior than that of the high dose group (p=0.044).

Conclusions

The iLC was improved along with increasing radiotherapy dose, but high dose had inferior iOS compared to low dose, while there were not significantly improving iLC when radiotherapy BED >56Gy. But in patients with DS-GPA≥2 subgroup, high dose brought better iLC benefits.

Propensity score-matched analysis comparing hippocampus-avoidance whole-brain radiotherapy plus simultaneous integrated boost with hippocampus‑avoidance whole-brain radiotherapy alone for multiple brain metastases-a retrospective study in multiple institutions

BACKGROUND

The optimal treatment for multiple brain metastases has been recently controversially discussed.This study was aimed to explore the feasibility of Hippocampus-Avoidance Whole-Brain Radiotherapy plus a simultaneous integrated boost (HA-WBRT + SIB) in patients with multiple brain metastases and assess tumor control in comparison with Hippocampus-Avoidance Whole-Brain Radiotherapy (HA-WBRT) alone for brain metastases.

METHODS

In this study, 63 patients with multiple brain metastases (≥ 4 metastases) had undergone HA-WBRT + SIB between January 2016 and December 2020 in the observation group:HA-WBRT (30 Gy in 12 fractions, the maximum dose of the hippocampus ≤ 14 Gy) plus a simultaneous integrated boost (48 Gy in 12 fractions) for brain metastases.Overall Survival (OS), Median survival,intracranial control (IC = control within the entire brain), intracranial progression-free survival (iPFS) and adverse events were compared with the control group (a HA-WBRT retrospective cohort) by propensity score matching analysis.

RESULTS

After 1:1 propensity score matching,there were 56 patients in each group (the observation group, the control group). OS, median survival and iPFS were significantly longer in the observation group (18.4 vs. 10.9 months, P<0.001), (13.0 vs. 8.0 months, P<0.001), (13.9 vs.7.8 months, P<0.001). In comparison of 1-year-IC rates, the observation group also demonstrated higher than the control group (51.8% vs. 21.4%, P = 0.002), respectively. Seven hippocampal metastases were found in the control group (4/56,7.1%) and the observation group (3/56,5.4%) after HA-WBRT. The death rate of intracranial progression were 23.2% in the observation group and 37.5% in the control group.All adverse events were not significant difference between the two groups (P>0.05).

CONCLUSIONS

HA-WBRT + SIB resulted in better OS,median survival, IC, iPFS, an acceptable risk of radiation response, and a potential way of declining neurocognitive adverse events, which may be a better treatment for patients with multiple brain metastases.

The Impact of Chemosensitivity on the Outcome of Brain Metastases in Small-Cell Lung Cancer: A Retrospective Analysis

PURPOSE

The purpose of this study was to investigate the prognostic differences between patients with small-cell lung cancer (SCLC) with different chemosensitivity to first-line chemotherapy who developed brain metastasis (BM) as the first site of progression.

METHODS

Patients with a BM after first-line treatment in the Tianjin Cancer Hospital were retrospectively analyzed. According to the time-free interval (TFI) between the completion of first-line chemotherapy and the onset of the BM, the patients were divided into the chemo-sensitive group (TFI ≥ 90 days, n = 145) and the chemo-resistant group (TFI < 90 days, n = 97). The survival time, which was calculated from the diagnosis of the BM, was analyzed after the onset of brain metastasis (BM-OS). Survival curves were plotted using the Kaplan-Meier method, and differences between groups were compared using the log-rank test.

RESULTS

In total, the median BM-OS was 8.4 months. The median BM-OS in the chemo-sensitive group was 8.8 months, and it was 8.0 months in the chemo-resistant group (p = 0.538). In patients without extracranial progression (n = 193), the median BM-OSes in the chemo-sensitive and chemo-resistant groups were 9.4 months and 9.7 months, respectively (p = 0.947). In patients with extracranial progression (n = 49), the median BM-OSes in the chemo-sensitive and chemo-resistant groups were 5.4 months and 4.2 months, respectively (p = 0.161). Conclusions: After the development of a BM as the first site of progression following chemotherapy in patients with SCLC, the prognosis of chemo-sensitive patients was not necessarily superior to chemo-resistant patients, especially in patients without extracranial progression.

The effect of smoking on survival in lung carcinoma patients with brain metastasis: a systematic review and meta-analysis

The effects of smoking on survival in BM patients have yet to be reviewed and meta-analysed. However, previous studies have shown that smokers had a greater risk of dying from lung cancer compared to non-smokers. This meta-analysis, therefore, aimed to analyse the effects of cigarette smoking on overall survival (OS) and progression-free survival (PFS) in lung cancer BM patients. PubMed, Embase, Web of Science, Cochrane and Google Scholar were searched for comparative studies regarding the effects of smoking on incidence and survival in brain metastases patients up to December 2020. Three independent reviewers extracted overall survival (OS) and progression-free survival data (PFS). Random-effects models were used to pool multivariate-adjusted hazard ratios (HR). Out of 1890 studies, fifteen studies with a total of 2915 patients met our inclusion criteria. Amongst lung carcinoma BM patients, those who were smokers (ever or yes) had a worse overall survival (HR: 1.34, 95% CI 1.13, 1.60, I2: 72.1%, p-heterogeneity < 0.001) than those who were non-smokers (never or no). A subgroup analysis showed the association to remain significant in the ever/never subgroup (HR: 1.34, 95% CI 1.11, 1.63) but not in the yes/no smoking subgroup (HR: 1.30, 95% CI 0.44, 3.88). This difference between the two subgroups was not statistically significant (p = 0.91). Amongst lung carcinoma BM patients, smoking was associated with a worse OS and PFS. Future studies examining BMs should report survival data stratified by uniform smoking status definitions.

Optimizing Whole Brain Radiotherapy Treatment and Dose for Patients With Brain Metastases From Small Cell Lung Cancer

Purpose

This study aimed to evaluate the survival outcomes of whole brain radiotherapy (WBRT) compared to whole brain radiotherapy plus local radiation boost (WBRT + boost), and further identify whether higher biologically effective dose (BED) of WBRT + boost translates into a survival benefit in small cell lung cancer (SCLC) patients with brain metastasis (BM).

Methods

SCLC patients with BM from January 1, 2012, to December 31, 2019, were retrospectively analyzed. Overall survival (OS) and intracranial progression-free survival (iPFS) were evaluated by the Kaplan–Meier method and compared by the log-rank test. Univariate and multivariate regression analyses of prognostic factors for OS were performed using Cox proportional hazards regression models. The cutoff value of BED was determined by the receiver operating characteristic (ROC) curve analysis.

Results

Among the 180 eligible patients, 82 received WBRT + boost and 98 received WBRT. Both OS and iPFS in the WBRT + boost group were significantly superior to those in the WBRT group (median OS: 20 vs. 14 months, p = 0.011; median iPFS: 16 vs. 10 months, p = 0.003). At a cutoff value of 58.35 Gy in the WBRT + boost group, 52 for the high-BED (>58.35 Gy) group, 30 for the low-BED (≤58.35 Gy) group. High BED was significantly associated with improved OS and iPFS compared with low BED in the WBRT + boost group (median OS: 23 vs. 17 months, p = 0.002; median iPFS: 17 vs. 10 months, p = 0.002).

Conclusions

Compared with WBRT alone, WBRT + boost improved OS and iPFS in SCLC patients with BM. High BED (>58.35 Gy) for WBRT + boost may be a reasonable consideration for SCLC patients with BM.

Feasibility of automated planning for whole-brain radiation therapy using deep learning

PURPOSE

The purpose of this study was to develop automated planning for whole-brain radiation therapy (WBRT) using a U-net-based deep-learning model for predicting the multileaf collimator (MLC) shape bypassing the contouring processes.

METHODS

A dataset of 55 cases, including 40 training sets, five validation sets, and 10 test sets, was used to predict the static MLC shape. The digitally reconstructed radiograph (DRR) reconstructed from planning CT images as an input layer and the MLC shape as an output layer are connected one-to-one via the U-net modeling. The Dice similarity coefficient (DSC) was used as the loss function in the training and ninefold cross-validation. Dose-volume-histogram (DVH) curves were constructed for assessing the automatic MLC shaping performance. Deep-learning (DL) and manually optimized (MO) approaches were compared based on the DVH curves and dose distributions.

RESULTS

The ninefold cross-validation ensemble test results were consistent with DSC values of 94.6 ± 0.4 and 94.7 ± 0.9 in training and validation learnings, respectively. The dose coverages of 95% target volume were (98.0 ± 0.7)% and (98.3 ± 0.8)%, and the maximum doses for the lens as critical organ-at-risk were 2.9 Gy and 3.9 Gy for DL and MO, respectively. The DL technique shows the consistent results in terms of the DVH parameter except for MLC shaping prediction for dose saving of small organs such as lens.

CONCLUSIONS

Comparable with the MO plan result, the WBRT plan quality obtained using the DL approach is clinically acceptable. Moreover, the DL approach enables WBRT auto-planning without the time-consuming manual MLC shaping and target contouring.

Whole Brain Radiation Therapy Plus Focal Radiation Boost May Generate Better Survival Benefit for Brain Metastases From Non-small Cell Lung Cancer

Background

Owing to improved systemic therapies, the survival of patients with non-small cell lung cancer (NSCLC) was prolonged, and the risk of brain metastases was consequently increased. This study aims to compare different radiotherapy for brain metastases in patients with NSCLC.

Materials and methods

The patients with NSCLC who were treated with whole brain radiation therapy (WBRT) or stereotactic radiosurgery (SRS) for brain metastases at three medical centers between January 2012 and December 2017 were retrospectively analyzed.

Results

Of the 684 eligible patients, 217 received WBRT plus focal radiation boost (WBRT+boost), 324 received WBRT, and 143 received SRS. Patients with WBRT+boost lived longer than those with WBRT (median overall survival (OS), 22.2 vs 13.7 months, P < 0.001) or SRS (22.2 vs 17.3 months, P = 0.011). In subgroup analyses, the survival advantage of WBRT+boost was more obvious among patients with 1 to 3 brain metastases or who received targeted therapy than did SRS. From pair-wise comparisons of intracranial progression-free survival (iPFS), WBRT+boost was also superior to WBRT (12.9 vs 10.6 months, P = 0.028) and SRS (12.9 vs 9.1 months, P = 0.001).

Conclusions

Patients who were treated with WBRT+boost experienced significantly longer OS and iPFS than those with WBRT or SRS alone. WBRT+boost should be a preferred strategy for brain metastases in NSCLC patients.

[Formula: see text]: deep learning-based radiomics for the time-to-event outcome prediction in lung cancer

Hand-crafted radiomics has been used for developing models in order to predict time-to-event clinical outcomes in patients with lung cancer. Hand-crafted features, however, are pre-defined and extracted without taking the desired target into account. Furthermore, accurate segmentation of the tumor is required for development of a reliable predictive model, which may be objective and a time-consuming task. To address these drawbacks, we propose a deep learning-based radiomics model for the time-to-event outcome prediction, referred to as DRTOP that takes raw images as inputs, and calculates the image-based risk of death or recurrence, for each patient. Our experiments on an in-house dataset of 132 lung cancer patients show that the obtained image-based risks are significant predictors of the time-to-event outcomes. Computed Tomography (CT)-based features are predictors of the overall survival (OS), with the hazard ratio (HR) of 1.35, distant control (DC), with HR of 1.06, and local control (LC), with HR of 2.66. The Positron Emission Tomography (PET)-based features are predictors of OS and recurrence free survival (RFS), with hazard ratios of 1.67 and 1.18, respectively. The concordance indices of [Formula: see text], [Formula: see text], and [Formula: see text] for predicting the OS, DC, and RFS show that the deep learning-based radiomics model is as accurate or better in predicting predefined clinical outcomes compared to hand-crafted radiomics, with concordance indices of [Formula: see text], [Formula: see text], and [Formula: see text], for predicting the OS, DC, and RFS, respectively. Deep learning-based radiomics has the potential to offer complimentary predictive information in the personalized management of lung cancer patients.

Tumor Primary Site and Histology Subtypes Role in Radiotherapeutic Management of Brain Metastases

Randomized controlled trials have failed to report any survival advantage for WBRT combined with SRS in the management of brain metastases, despite the enhanced local and distant control in comparison to each treatment alone. Literature review have revealed important role of primary histology of the tumor when dealing with brain metastases. NSCLC responds better to combined approach even when there was only single brain metastasis present while breast cancer has registered better survival with SRS alone probably due to better response of primary tumor to advancement in surgical and chemotherapeutic agents. Furthermore, mutation status (EGFR/ALK) in lung cancer and receptor status (ER/PR/HER2) in breast cancer also exhibit diversity in their response to radiotherapy. Radioresistant tumors like renal cell carcinoma and melanoma brain metastases have achieved better results when treated with SRS alone. Secondly, single brain metastasis may benefit from local and distant brain control achieved with combined treatment. These diverse outcomes suggest a primary histology-based analysis of the radiotherapy regimens (WBRT, SRS, or their combination) would more ideally establish the role of radiotherapy in the management of brain metastases. Molecularly targeted therapeutic and immunotherapeutic agents have revealed synergism with radiation therapy particularly SRS in treating cancer patients with brain metastases. Clinical updates in this regard have also been reviewed.

Brain Metastasis Organotropism

Brain metastases are associated with poor prognosis irrespective of the primary tumor they originate from. Current treatments for brain metastases are palliative, and patients with symptomatic brain metastasis have a one-year survival of <20%. Lung cancer, breast cancer, and melanoma have higher incidences of brain metastases compared with other types of cancers. However, it is not very clear why some cancers metastasize to the brain more frequently than others. Studies thus far suggest that brain-specific tropism of certain types of cancers is defined by a winning combination of the following factors: unique genetic subtypes of primary tumors or its subclones enabling detachment, dissemination, blood-brain barrier penetration, plus proliferation and survival in hypoxic low-glucose microenvironment; specific transcriptomic and epigenetic changes of colony-forming metastatic cells, allowing their outgrowth; favorable metastasis-permissive microenvironment of the brain created by interactions of cancer cells and cells in the brain through triggering inflammation, recruiting myeloid-derived suppressor cells, and promoting metabolic adaptation; immunosuppression resulting in the failure of adaptive immune response to recognize or kill cancer cells in the brain. Here, we briefly review recent advances in understanding brain metastasis organotropism and outline directions for future research.

High Biologically Effective Dose Radiotherapy for Brain Metastases May Improve Survival and Decrease Risk for Local Relapse Among Patients With Small-Cell Lung Cancer: A Propensity-Matching Analysis

To evaluate whether high biologically effective dose (BED) radiotherapy improves local control and survival outcomes for patients with brain metastases (BMs) from small-cell lung cancer (SCLC) and to determine possible prognostic factors. From January 1998 to June 2018, 250 patients with BM from SCLC were retrospectively analyzed. The Cutoff Finder program was used to classify patients by BED. Overall survival (OS) and BM progression-free survival (BM-PFS) were analyzed using the Kaplan-Meier method and log-rank test. A Cox regression model was used to calculate the hazard ratio and 95% CI for prognostic factors for OS among the study population and propensity score (PS)-matched patients. A BED of 47.4 was taken as the optimal cutoff value. Both OS and BM-PFS were significantly improved in the high-BED (>47.4 Gy) than in the low-BED (≤47.4 Gy) group (median OS: 17.5 months vs 9.5 months, P < .001, median BM-PFS: 14.4 months vs 8.3 months, P < .001). Biologically effective dose (P < .001), Eastern Cooperative Oncology Group performance status (P = .047), smoking (P = .005), and pleural effusion (P = .004) were independent prognostic factors for OS. Propensity score matching with a ratio of 1:2 resulted in 57 patients in the high-BED group and 106 patients in the low-BED group. In the PS-matched cohort, OS and BM-PFS were significantly prolonged in the high-BED group compared with the low-BED group (P < .001). Biologically effective dose >47.4 Gy improves survival among patients with BM from SCLC. Eastern Cooperative Oncology Group score, smoking, and pleural effusion independently affect OS of SCLC patients with BM.

Whole brain radiation therapy plus focal boost may be a suitable strategy for brain metastases in SCLC patients: a multi-center study

Background

The treatment for brain metastases in small cell lung cancer (SCLC) is still controversial. The purpose of this study was to compare different brain radiotherapy treatments on SCLC patients with brain metastases.

Methods

In this multi-center retrospective study, SCLC patients who had undergone whole brain radiation therapy (WBRT) or stereotactic radiosurgery (SRS) for brain metastases from January 2012 to December 2018 were retrospectively screened.

Results

A total of 263 eligible SCLC patients were included in this study, among whom, 73 were women and 190 were men. According to accepted brain radiotherapy, the remaining patients were divided into WBRT plus focal radiation boost (WBRT+boost), WBRT, and SRS groups. In pairwise comparisons of the overall survival (OS), WBRT+boost group led to longer survival than did WBRT both in all patients (17.9 vs 8.7 months; P < 0.001) and 140 matched patients (17.9 vs 11.7 months; P = 0.045). There were no significant differences in OS between WBRT+boost and SRS groups in all patients (17.9 vs 14.5 months; P = 0.432). Among 74 matched patients between WBRT+boost and SRS groups, however, patients who received WBRT+boost led to a longer survival than did SRS alone (21.8 vs 12.9 months; P = 0.040). In pairwise comparison of the intracranial progression-free survival time (iPFS), WBRT+boost group also showed survival advantages over WBRT (10.8 vs 6.5 months; P = 0.005) and SRS groups (10.8 vs 7.5 months; P = 0.032).

Conclusion

Due to the SCLC-derived multiple brain metastases and better survival time, focal radiation boost combined with adjuvant WBRT may be a preferred strategy for SCLC patients with brain metastases.

A noteworthy treatment of metastatic small-cell lung cancer with afatinib, followed by subsequent development of rare metastatic lesions in the ascending and sigmoid colon

BACKGROUND

Small-cell lung cancer (SCLC) represents a group of highly fatal diseases with a tendency toward fast growth, early metastasis, and easy development of chemotherapy resistance. In the past 30 years, few advances have been made in the systemic treatment of SCLC, and cisplatin/etoposide has remained the standard of care for limited-stage SCLC and, in combination with radiotherapy, extensive-stage SCLC. The preferred metastatic sites of SCLC include the brain, liver, adrenal glands, bone, and bone marrow. However, bowel metastasis caused by SCLC is extremely rarely proved in patients while they are still alive (although autopsy studies suggest that silent metastases to the bowel are more common), and the standard treatment for bowel metastasis has never been reported. The mean time between the identification of gastrointestinal metastasis and mortality in patients with lung cancer is 100.6 days, with a range of 21-145 days.

CASE

We report the case of a patient with extensive SCLC (including brain metastasis), in which exon 19 deletion of epidermal growth factor receptor (EGFR) was detected. She initially refused chemotherapy and cranial radiotherapy and instead only agreed to oral target therapy. The second-generation EGFR-tyrosine kinase inhibitor (TKI), afatinib, was administered to the patient, and partial remission, including smaller metastatic brain tumors, was noted. Even though the subsequent development of rare metastatic lesions in the ascending and sigmoid colon was proved by colonoscopic biopsies, the prolonged overall survival (400 days) without standard treatment was marked in this case.

CONCLUSION

The patient with extensive metastasis of SCLC did not receive standard systemic chemotherapy. Instead, she initially received second-generation EGFR-TKI afatinib alone and later on whole brain radiotherapy as well (3 weeks before she expired). The prolonged overall survival of 400 days was marked and is worthy of sharing and further investigation.