Meier Hsu

Frequency and Distinctive Spectrum of KRAS Mutations in Never Smokers with Lung Adenocarcinoma

Purpose:KRAS mutations are found in ∼25% of lung adenocarcinomas in Western countries and, as a group, have been strongly associated with cigarette smoking. These mutations are predictive of poor prognosis in resected disease as well as resistance to treatment with erlotinib or gefitinib. Experimental Design: We determined the frequency and type of KRAS codon 12 and 13 mutations and characterized their association with cigarette smoking history in patients with lung adenocarcinomas. Results:KRAS mutational analysis was done on 482 lung adenocarcinomas, 81 (17%) of which were obtained from patients who had never smoked cigarettes. KRAS mutations were found in 15% (12 of 81; 95% confidence intervals, 8-24%) of tumors from never smokers. Similarly, 22% (69 of 316; 95% confidence intervals, 17-27%) of tumors from former smokers, and 25% (21 of 85; 95% confidence intervals, 16-35%) of tumors from current smokers had KRAS mutations. The frequency of KRAS mutation was not associated with age, gender, or smoking history. The number of pack years of cigarette smoking did not predict an increased likelihood of KRAS mutations. Never smokers were significantly more likely than former or current smokers to have a transition mutation (G→A) rather than the transversion mutations known to be smoking-related (G→T or G→C; P < 0.0001). Conclusions: Based on our data, KRAS mutations are not rare among never smokers with lung adenocarcinoma and such patients have a distinct KRAS mutation profile. The etiologic and biological heterogeneity of KRAS mutant lung adenocarcinomas is worthy of further study.

Impact of Dose on Local Failure Rates After Image-Guided Reirradiation of Recurrent Paraspinal Metastases

PURPOSE To examine the impact of dose on local failure (LF) rates in the re-treatment of recurrent paraspinal metastases with image-guided intensity-modulated radiotherapy (IG-IMRT). METHODS AND MATERIALS The records of patients with in-field recurrence after previous spine radiation (median dose, 30 Gy) who received salvage IG-IMRT with either five 4-Gy (20-Gy group, n = 42) or five 6-Gy (30-Gy group, n = 55) daily fractions between January 2003 and August 2008 were reviewed. Institutional practice was 20 Gy before April 2006, when it changed to 30 Gy. A total of 47 cases (48%) were treated adjuvantly, after surgery to decompress epidural disease. LF after IG-IMRT was defined radiographically. RESULTS The median follow-up was 12.1 months (range, 0.2-63.6 months). The 1-year cumulative incidences of LF after 20 Gy and 30 Gy IG-IMRT were 45% and 26%, respectively (p = 0.04). Of all treatment characteristics examined (20-Gy vs. 30-Gy dose group, dose to 95% of the planned and gross target volume, tumor size, histology, receipt of surgery, and interval between first and second radiation), only dose group had a significant impact on actuarial LF incidence (p = 0.04; unadjusted HR, 0.51; 95% CI, 0.27-0.96). There was no incidence of myelopathy. CONCLUSIONS A significant decrease in LF after IG-IMRT with five 6-Gy fractions compared with five 4-Gy fractions was observed without increased risk of myelopathy. Until prospective data comparing stereotactic hypofractionated and single-fraction regimens become available, when reirradiating recurrent paraspinal metastases with IG-IMRT, administration of five 6-Gy daily fractions is reasonable.

Toxicity and outcomes of thoracic re-irradiation using stereotactic body radiation therapy (SBRT)

BackgroundPatients treated for a thoracic malignancy carry a significant risk of developing other lung lesions. Locoregional control of intrathoracic recurrences is challenging due to the impact of prior therapies on normal tissues. We examined the safety and efficacy of thoracic re-irradiation using high-precision image-guided stereotactic body radiation therapy (SBRT).MethodsRecords of 39 patients with prior intra-thoracic conventionally fractionated radiation therapy (RT) who underwent SBRT for a subsequent primary, recurrent or metastatic lung tumor from 11/2004 to 7/2011 were retrospectively reviewed.ResultsMedian dose of prior RT was 61 Gy (range 30–80 Gy). Median biologically effective prescription dose (α/β = 10) (BED10) of SBRT was 70.4 Gy (range 42.6-180 Gy). With a median followup of 12.6 months among survivors, 1- and 2-year actuarial local progression-free survival (LPFS) were 77% and 64%, respectively. Median recurrence-free (RFS) and overall survival (OS) were 13.8 and 22.0 months, respectively. Patients without overlap of high-dose regions of the primary and re-irradiation plans were more likely to receive a BED10 ≥100 Gy, which was associated with higher LPFS (hazard ratio, [HR] = 0.18, p = 0.04), RFS ([HR] = 0.31, p = 0.038) and OS ([HR] = 0.25, p = 0.014). Grade 2 and 3 pulmonary toxicity was observed in 18% and 5% of patients, respectively. Other grade 2–4 toxicities included chest wall pain in 18%, fatigue in 15% and skin toxicity in 5%. No grade 5 events occurred.ConclusionsSBRT can be safely and successfully administered to patients with prior thoracic RT. Dose reduction for cases with direct overlap of successive radiation fields results in acceptable re-treatment toxicity profile.

HER2 Amplification and HER2 Mutation Are Distinct Molecular Targets in Lung Cancers

Introduction: Human epidermal growth factor receptor 2 gene (HER2 [also known as ERBB2]) alterations have been identified as oncogenic drivers and potential therapeutic targets in lung cancers. The molecular associations of HER2 gene amplification, mutation, and HER2 protein overexpression in lung cancers have not been distinctly defined. To explore these associations, Memorial Sloan Kettering Cancer Center and the University of Colorado combined their data on HER2 alterations in lung cancers. Methods: Tumor specimens from 175 patients with lung adenocarcinomas and no prior targeted therapy were evaluated for the presence of HER2 amplification and mutation and HER2 protein overexpression. Amplification was assessed by fluorescence in situ hybridization (FISH) and defined as an HER2‐to‐chromosome enumeration probe 17 ratio of at least 2.0. Mutation was assessed by fragment analysis, mass spectrometry genotyping, and Sanger sequencing. Overexpression was assessed by immunohistochemical (IHC) staining. The frequencies of HER2 amplification and mutation and HER2 overexpression were calculated and their overlap examined. Results: HER2 amplification was detected by FISH in 5 of 175 cases (3%). HER2 mutation was detected in 4 of 148 specimens (3%), including three identical 12–base pair insertions (p.A775_G776insYVMA) and a 9–base pair insertion, all in exon 20. None of the HER2‐mutant cases was amplified. HER2 overexpression (2+ or 3+) on IHC staining was not detected in the 25 specimens available for testing, and negative IHC staining correlated with the negative results according to FISH. Conclusions: HER2 mutations are not associated with HER2 amplification, thus suggesting a distinct entity and therapeutic target. HER2‐positive lung cancer may not be an adequate term, and patient cohorts for the study of HER2‐targeted agents should be defined by the specific HER2 alteration present.

Outcomes of Patients Undergoing Percutaneous Biliary Drainage to Reduce Bilirubin for Administration of Chemotherapy

PURPOSE To describe outcomes in patients undergoing percutaneous biliary drainage to reduce total serum bilirubin level for administration of chemotherapy. MATERIALS AND METHODS A total of 647 consecutive patients underwent percutaneous biliary drainage between September 2001 and December 2008. In 168, the indication for biliary drainage was to decrease total serum bilirubin level to permit administration of chemotherapy. Of these, 20 were excluded because they had hepatic arterial infusion pumps, leaving 148 patients as the study group. The primary diagnoses for these patients were gallbladder cancer (n = 23), cholangiocarcinoma (n = 21), pancreatic cancer (n = 36), and other metastatic cancers (n = 68). Medical records and imaging studies were reviewed for demographic data, procedural information, pre- and postdrainage total serum bilirubin level levels, 30-day complications, and subsequent biliary procedures. RESULTS The probability of attaining a total serum bilirubin level of 1 mg/dL or lower by 100 days was 31% (95% CI, 23%-39%). Predrainage total serum bilirubin level of 9 mg/dL or lower (hazard ratio [HR], 3.27; 95% CI, 1.86-5.75; P < .001), 100% liver drainage (HR 2.73, 95% CI, 1.56-4.78; P <.001), and lower predrainage International Normalized Ratio (INR; HR, 0.80; 95% CI, 0.70-0.92; P = .002) were associated with an increased likelihood of attaining a total serum bilirubin level of 1 mg/dL or lower. The most common indication for follow-up was pericatheter leakage, which occurred in nearly one third of cases. During follow-up, patients required three visits per 100 catheter-days, or approximately one per month. Median overall survival in this population was approximately 3.5 months. CONCLUSIONS Only 31% of patients attained a normal serum bilirubin level by 100 days, and median overall survival was 107 days. Careful patient selection is warranted before biliary drainage for this indication. Maximal biliary drainage, a preprocedure total serum bilirubin of less than 9 mg/dL, and a lower INR were factors associated with serum bilirubin normalization in this cohort.

Long-Term Outcomes and Patterns of Relapse of Early-Stage Extranodal Marginal Zone Lymphoma Treated With Radiation Therapy With Curative Intent

PURPOSE To report the long-term outcome and patterns of relapse of a large cohort of marginal zone lymphoma (MZL) patients treated with curative-intent radiation therapy (RT) alone. PATIENTS AND METHODS We reviewed the charts of 490 consecutive patients with stage IE or IIE MZL referred between 1992 and 2012 to our institution. Of those, 244 patients (50%) were treated with RT alone. Pathology was confirmed by hematopathologists at our institution. Patient and disease factors were analyzed for association with relapse-free survival (RFS) and overall survival (OS). RESULTS Median age of the cohort was 59 years, and median follow-up was 5.2 years. Ann Arbor stage was IE in 92%. Most common disease sites were stomach (50%), orbit (18%), non-thyroid head-and-neck (8%), skin (8%), and breast (5%). Median RT dose was 30 Gy. Five-year OS and RFS were 92% and 74%, respectively. Cumulative incidence of disease-specific death was just 1.1% by 5 years. Sixty patients (24%) developed relapse of disease; 10 were in the RT field. Crude rate of transformation to pathologically confirmed large-cell lymphoma was 1.6%. On multivariable analysis, primary disease site (P=.007) was independently associated with RFS, along with age (P=.04), presence of B-symptoms (P=.02), and International Prognostic Index risk group (P=.03). All disease sites except for head-and-neck had worse RFS relative to stomach. CONCLUSION Overall and cause-specific survival are high in early-stage extra-nodal MZL treated with curative RT alone. In this large cohort of 244 patients, most patients did not experience relapse of MZL after curative RT; when relapses did occur, the majority were in distant sites. Stomach cases were less likely to relapse than other anatomic sites. Transformation to large-cell lymphoma was rare.

Recurrent non-small cell lung cancer: evaluation of CT-guided radiofrequency ablation as salvage therapy.

Background Radiofrequency ablation (RFA) is a potential application as a salvage tool after failure of surgery, chemotherapy, or radiotherapy of non-small cell lung cancer (NSCLC). Although several studies have evaluated the use of RFA in primary NSCLC, there is little literature on its potential application as a salvage tool. Purpose To evaluate CT-guided RFA employed as a salvage therapy for pulmonary recurrences of NSCLC after prior treatment with chemotherapy, radiation therapy, and/or surgery. Material and Methods A retrospective computer database search yielded 33 patients with biopsy proven primary NSCLC who underwent CT-guided RFA of 39 recurrent tumors following surgery, chemotherapy, and/or radiotherapy. Follow-up imaging was performed with CT and PET-CT. The endpoints of interest were progression-free survival (PFS) and time to local progression (TTLP). PFS and TTLP were compared by lesion size (<3 cm, ≥3 cm). Results The median PFS was 8 months. For patients with a tumor size <3 cm median PFS was 11 months, whereas the median PFS of patients with a tumor size ≥3 cm was 5 months. The difference did not reach statistical significance (P = 0.09). The median TTLP of all tumors was 14 months. TTLP of ablated tumors <3 cm in size was 24 months, compared to 8 months for ablated tumors ≥3 cm in size. The difference did not reach statistical significance (P = 0.07). Conclusion RFA of recurrent NSCLC may be a valuable salvage tool to achieve local tumor control, especially in tumors measuring <3 cm in size.

A Prospective Study of Total Plasma Cell-Free DNA as a Predictive Biomarker for Response to Systemic Therapy in Patients with Advanced Non-Small Cell Lung Cancers

BACKGROUND While previous studies have reported on the prognostic value of total plasma cell-free deoxyribonucleic acid (cfDNA) in lung cancers, few have prospectively evaluated its predictive value for systemic therapy response. PATIENTS AND METHODS We conducted a prospective study to evaluate the association between changes in total cfDNA and radiologic response to systemic therapy in patients with stage IIIB/IV non-small-cell lung cancers (NSCLCs). Paired blood collections for cfDNA and computed tomography (CT) assessments by RECIST v1.0 were performed at baseline and 6-12 weeks after therapy initiation. Total cfDNA levels were measured in plasma using quantitative real-time polymerase chain reaction. Associations between changes in cfDNA and radiologic response, progression-free survival (PFS), and overall survival (OS) were measured using Kruskal-Wallis and Kaplan-Meier estimates. RESULTS A total of 103 patients completed paired cfDNA and CT response assessments. Systemic therapy administered included cytotoxic chemotherapy in 57% (59/103), molecularly targeted therapy in 17% (17/103), and combination therapy in 26% (27/103). Median change in cfDNA from baseline to response assessment did not significantly differ by radiologic response categories of progression of disease, stable disease and partial response (P = 0.10). However, using radiologic response as continuous variable, there was a weak positive correlation between change in radiologic response and change in cfDNA (Spearmans correlation coefficient 0.21, P = 0.03). Baseline cfDNA levels were not associated with PFS [hazard ratio (HR) = 1.06, 95% confidence interval (CI) 0.93-1.20, P = 0.41] or OS (HR = 1.04, 95% CI 0.93-1.17, P = 0.51), neither were changes in cfDNA. CONCLUSIONS In this large prospective study, changes in total cfDNA over time did not significantly predict radiologic response from systemic therapy in patients with advanced NSCLC. Pretreatment levels of total cfDNA were not prognostic of survival. Total cfDNA level is not a highly specific predictive biomarker and future investigations in cfDNA should focus on tumor-specific genomic alterations using expanded capabilities of next-generation sequencing.

Overall survival among older U.S. adults with ALL remains low despite modest improvement since 1980: SEER analysis

To the editor: Over the past 4 decades, outcomes have improved dramatically among pediatric patients with acute lymphoblastic leukemia (ALL), with observed cure rates now >80% in developed countries.[1][1] This progress can be attributed, in part, to large cooperative group studies, advances in

Stereotactic Body Radiation Therapy for Primary Lung Cancers >3 Centimeters

Introduction: A retrospective analysis of the outcomes of stereotactic body radiation therapy (SBRT) in the treatment of large (>3 cm) non–small-cell lung cancers (NSCLCs). Methods: Between February 2007 and November 2011, 63 patients with T2-T4N0 NSCLC were treated with SBRT. Toxicity was graded per Common Terminology Criteria for Adverse Events, version 4.0. Local failure-free survival (LFFS), recurrence-free survival, and overall survival curves were estimated using the Kaplan–Meier method and univariate analysis was performed using Cox regression. Results: Median follow-up was 16.9 months. One- and 2-year LFFS was 88.8% and 75.7%, 1- and 2-year recurrence-free survival was 59.0% and 41.6%, and 1- and 2-year overall survival was 77.1% and 57.6%, respectively. Planning target volume less than 106 cm3 was associated with a significantly higher 1- and 2-year LFFS (p =0.05). Grade 2 or higher acute and late pulmonary toxicities occurred in 19.3% and 19.3% of patients, respectively, and were not associated with common dose–volume parameters; 22.8% of patients developed grade 2 or higher chest wall pain, which was significantly associated with chest wall V30 70 cm3 or more (p = 0.03). Conclusions: SBRT for larger NSCLC tumors achieves high LFFS with acceptable toxicity. LFFS was worse with planning target volume 106 cm3 or more. Grade 2 or higher chest wall pain was associated with chest wall V30 70 cm3 or more.