Reginald F. Munden

Interobserver and Intraobserver Variability in Measurement of Non–Small-Cell Carcinoma Lung Lesions: Implications for Assessment of Tumor Response

PURPOSE Response of solid malignancies to therapy is usually determined by serial measurements of tumor size. The purpose of our study was to assess the consistency of measurements performed by readers evaluating lung tumors. MATERIALS AND METHODS The study group was composed of 33 patients with lung tumors more than 1.5 cm. Bidimensional (BD) and unidimensional (UD) measurements were performed on computed tomography (CT) scans according to the World Health Organization (WHO) criteria and the Response Evaluation Criteria in Solid Tumors (RECIST), respectively. Measurements were performed independently by five thoracic radiologists using printed film and were repeated after 5 to 7 days. Inter- and intraobserver measurement variations were estimated through statistical modeling. RESULTS There were 40 tumors with an average size of 1.8 to 8.0 cm (mean, 4.1 cm). Analysis of variance showed a significant difference (P <.05) among readers and among the measured nodules for UD and BD measurements. Interobserver misclassification rates were more than intraobserver misclassification rates using either progressive disease or response criteria. The probability of misclassifying a tumor with the WHO criteria or RECIST was greatest with interobserver measurements when criteria for progression (43% BD, 30% UD) were used and lowest with intraobserver measurements when criteria for response (2.5% BD, 3.0% UD) were used. In addition, interobserver misclassification rates were more than intraobserver misclassification rates for both regular and irregular tumors. CONCLUSION Measurements of lung tumor size on CT scans are often inconsistent and can lead to an incorrect interpretation of tumor response. Consistency can be improved if the same reader performs serial measurements for any one patient.

The American Association for Thoracic Surgery guidelines for lung cancer screening using low-dose computed tomography scans for lung cancer survivors and other high-risk groups

OBJECTIVE Lung cancer is the leading cause of cancer death in North America. Low-dose computed tomography screening can reduce lung cancer-specific mortality by 20%. METHOD The American Association for Thoracic Surgery created a multispecialty task force to create screening guidelines for groups at high risk of developing lung cancer and survivors of previous lung cancer. RESULTS The American Association for Thoracic Surgery guidelines call for annual lung cancer screening with low-dose computed tomography screening for North Americans from age 55 to 79 years with a 30 pack-year history of smoking. Long-term lung cancer survivors should have annual low-dose computed tomography to detect second primary lung cancer until the age of 79 years. Annual low-dose computed tomography lung cancer screening should be offered starting at age 50 years with a 20 pack-year history if there is an additional cumulative risk of developing lung cancer of 5% or greater over the following 5 years. Lung cancer screening requires participation by a subspecialty-qualified team. The American Association for Thoracic Surgery will continue engagement with other specialty societies to refine future screening guidelines. CONCLUSIONS The American Association for Thoracic Surgery provides specific guidelines for lung cancer screening in North America.

Pleural Effusion in Patients With Chronic Myelogenous Leukemia Treated With Dasatinib After Imatinib Failure

PURPOSE We investigated the risk factors and management of pleural effusion associated with dasatinib therapy for chronic myelogenous leukemia (CML) after failure of imatinib. PATIENTS AND METHODS We analyzed 138 patients with CML treated with dasatinib from November 2003 to January 2006 in one phase I (n = 50) and four phase II (n = 88) studies for the development of pleural effusion. RESULTS Pleural effusion occurred in 48 patients (35%; grade 3/4 in 23 [17%]), including 29% of those treated in chronic phase (CP), 50% in accelerated phase (AP), and 33% in blast phase (BP). By multivariate analysis, history of cardiac disease, hypertension, and use of a twice-daily schedule (v once daily) were identified as factors associated with development of pleural effusions. Effusions were exudative in 78% of the assessable cases. In some patients, effusions were associated with reversible increments of right ventricular systolic pressure. Management included transient dasatinib interruption in 83%, diuretics in 71%, pulse steroids in 27%, and thoracentesis in 19% of patients. CONCLUSION Pleural effusions occur during dasatinib therapy, particularly among patients in AP or BP. A twice-daily schedule may result in a higher incidence of pleural effusion. Close monitoring and timely intervention may allow patients to continue therapy and achieve the desired clinical benefit.

Respiratory-driven lung tumor motion is independent of tumor size, tumor location, and pulmonary function

PURPOSE To determine whether superior-inferior lung tumor motion is predictable by tumor size or location, or pulmonary function test results. METHODS AND MATERIALS Superior-inferior tumor motion was measured on orthogonal radiographs taken during simulation of 22 patients with inoperable lung cancer diagnosed by orthogonal radiographs. RESULTS The tumor size averaged 5.5 +/- 3.1 cm (range 1.5-12 cm). Seven of 11 central tumors demonstrated some motion compared with 5 of 11 peripheral tumors. Four of 5 upper lobe tumors moved compared with 8 of 17 tumors that were either middle or lower lobe lesions. The mean fourth rib motion was 7.3 +/- 3.2 mm (range 2-15). The mean FeV(1) was 1.8 +/- 1.2 (range 0.55-5.33. The mean diffusing capacity of the lung for carbon monoxide was 14.0 +/- 6.5 (range 7.8-21.9). The mean total lung capacity was 6.5 +/- 1.2 (range 3.3-8.4). None of these parameters correlated with tumor motion. Although lateral tumor motion could not be consistently determined, 1 tumor moved 10 mm anterior-posteriorly. CONCLUSIONS Lung tumors often move significantly during respiration. Tumor motion is not predictable by tumor size or location, or pulmonary function test results. Therefore, tumor motion must be measured in all patients. Measurement in three dimensions will likely be necessary to maximize the irradiated lung volumes or choose beam arrangements parallel to the major axis of motion.

A multidisciplinary surgical approach to superior sulcus tumors with vertebral invasion

BACKGROUND Vertebral body invasion by superior sulcus tumor has traditionally been considered a contraindication to surgical resection. Attempts at definitive radiation or chemoradiation have not been successful. Recent advances in spinal instrumentation have allowed more complete resection of vertebral body tumors. We, therefore, reviewed our recent experience with vertebral resection of superior sulcus tumors. METHODS All patients (n = 17) undergoing resection of superior sulcus tumors with T4 involvement of the vertebrae from October 18, 1990 to September 21, 1998 at the University of Texas M.D. Anderson Cancer Center (MDACC) were evaluated. Their clinical and pathologic data were reviewed and analyzed for short- and long-term outcomes. RESULTS Total vertebrectomy was performed in 7 patients (42%), partial vertebrectomy in 7 (42%), and 3 (18%) underwent neural foramina or transverse process resection. The median hospital stay was 11 days. Postoperative complications occurred in 7 patients (42%) and included pneumonia (6, 36%), arrhythmia (2, 12%), cerebrospinal fluid leak (2, 12%), wound breakdown (1, 6%), and reoperation for bleeding (1, 6%). Sixteen out of 17 patients received preoperative or postoperative radiation therapy. No perioperative mortality occurred. All patients remained ambulatory after spinal reconstruction. Overall actuarial survival at 2 years was 54%, with 11 patients still alive 2 to 50 months after resection. Locoregional tumor recurrence was noted in all 6 patients who had positive surgical margins, as opposed to 1 out of 11 patients (9%) with negative margins (p < 0.006). Additionally, the 2-year actuarial survival of patients with negative microscopic margins was 80% versus 0% for positive margins (p < 0.0006). CONCLUSIONS An aggressive multidisciplinary approach to superior sulcus tumors with vertebral invasion can lead to long-term survival with acceptable morbidity if negative margins can be obtained. Vertebral body invasion should no longer be considered a contraindication for resection of superior sulcus tumors.

Quantifying the Effect of IV Contrast Media on Integrated PET/CT: Clinical Evaluation

OBJECTIVES The use of IV contrast media in PET/CT can result in an overestimation of PET attenuation factors that potentially can affect interpretation. The objective of this study was to quantify the effect of IV contrast media in PET/CT and assess its impact on patients with intrathoracic malignancies. MATERIALS AND METHODS Nine patients had CTs performed with and without IV contrast media followed by (18)F-FDG PET. PET images were reconstructed using contrast-enhanced and unenhanced CT. To quantify the effect of contrast media on standardized uptake values (SUV), similar regions of interest (ROIs) were drawn on the subclavian vein, heart, liver, spleen, and site of malignancy on both CT and corresponding reconstructed PET images, and the mean and maximum values were compared. In addition, two physicians blinded to the imaging parameters that were used evaluated the reconstructed PET images to assess whether IV contrast media had an effect on clinical interpretation. RESULTS For all patient studies, the subclavian vein region on the ipsilateral side of contrast media administration had the highest increase in CT numbers with a corresponding average SUV(max) increase of 27.1%. Similarly, ROIs of the heart and at the site of malignancy showed an increase in the maximum attenuation value with a corresponding average SUV(max) increase of 16.7% and 8.4%, respectively. Other locations had relatively small attenuation value differences with a correspondingly negligible SUV variation. CONCLUSION Although there is a significant increase in SUV in regions of high-contrast concentration when contrast-enhanced CT is used for attenuation correction, this increase is clinically insignificant. Accordingly, in PET/CT, IV contrast-enhanced CT can be used in combination with the PET to evaluate patients with cancer.

Multi-Institutional Phase I/II Trial of Oral Bexarotene in Combination With Cisplatin and Vinorelbine in Previously Untreated Patients With Advanced Non–Small-Cell Lung Cancer

PURPOSE Bexarotene (Targretin; Ligand Pharmaceuticals, Inc, San Diego, CA) is a retinoid-X-receptor (RXR)-selective retinoid with preclinical antitumor activity in squamous cell cancers. In this phase I/II trial, we combined bexarotene with cisplatin and vinorelbine in the treatment of patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Forty-three patients who had stage IIIB NSCLC with pleural effusion or stage IV NSCLC and had received no prior therapy received bexarotene in combination with cisplatin (100 mg/m2) and vinorelbine (alternating doses of 30 mg/m2 and 15 mg/m2). In the phase I portion, the daily dose of bexarotene was escalated in cohorts of three patients from 150 mg/m2 to 600 mg/m2, beginning 1 week before the start of the cisplatin-vinorelbine regimen. Once the maximum-tolerated dose (MTD) of bexarotene was determined, the study entered the phase II portion. Response rate was the primary end point; median survival time and 1-year survival rate were secondary end points. RESULTS In the phase I portion, the daily MTD of bexarotene was determined to be 400 mg/m2. Eight of 43 patients exhibited major responses. Seven (25%) of the 28 patients in the phase II portion responded to treatment. The median survival time in the phase II portion was 14 months; nine (32%) of the 28 patients were still alive at a minimum follow-up of 2 years. One-year and projected 3-year survival rates were 61% and 30%, respectively. The most common grade 3 and 4 adverse events were hyperlipemia, leukopenia, nausea, vomiting, pneumonia, dyspnea, anemia, and asthenia. Grade 3 and 4 laboratory abnormalities with incidences greater than 5% were decreased hemoglobin levels and WBC, absolute neutrophil, and absolute lymphocyte counts and increased prothrombin time and creatinine and amylase levels. Of the two cases of pancreatitis, one required hospitalization and both were associated with increased triglyceride levels. There was one death secondary to renal insufficiency unrelated to bexarotene treatment. CONCLUSION In patients with advanced NSCLC, bexarotene with cisplatin and vinorelbine yielded acceptable phase II response rates (25%) and was associated with better-than-expected survival (14-month median survival time; 61% 1-year, 32% 2-year, and 30% projected 3-year survival rates). The regimen should be studied in larger clinical trials.

Prediction of Survival by [18F]Fluorodeoxyglucose Positron Emission Tomography in Patients With Locally Advanced Non–Small-Cell Lung Cancer Undergoing Definitive Chemoradiation Therapy: Results of the ACRIN 6668/RTOG 0235 Trial

PURPOSE In this prospective National Cancer Institute-funded American College of Radiology Imaging Network/Radiation Therapy Oncology Group cooperative group trial, we hypothesized that standardized uptake value (SUV) on post-treatment [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) correlates with survival in stage III non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Patients received conventional concurrent platinum-based chemoradiotherapy without surgery; postradiotherapy consolidation chemotherapy was allowed. Post-treatment FDG-PET was performed at approximately 14 weeks after radiotherapy. SUVs were analyzed both as peak SUV (SUVpeak) and maximum SUV (SUVmax; both institutional and central review readings), with institutional SUVpeak as the primary end point. Relationships between the continuous and categorical (cutoff) SUVs and survival were analyzed using Cox proportional hazards multivariate models. RESULTS Of 250 enrolled patients (226 were evaluable for pretreatment SUV), 173 patients were evaluable for post-treatment SUV analyses. The 2-year survival rate for the entire population was 42.5%. Pretreatment SUVpeak and SUVmax (mean, 10.3 and 13.1, respectively) were not associated with survival. Mean post-treatment SUVpeak and SUVmax were 3.2 and 4.0, respectively. Post-treatment SUVpeak was associated with survival in a continuous variable model (hazard ratio, 1.087; 95% CI, 1.014 to 1.166; P = .020). When analyzed as a prespecified binary value (≤ v > 3.5), there was no association with survival. However, in exploratory analyses, significant results for survival were found using an SUVpeak cutoff of 5.0 (P = .041) or 7.0 (P < .001). All results were similar when SUVmax was used in univariate and multivariate models in place of SUVpeak. CONCLUSION Higher post-treatment tumor SUV (SUVpeak or SUVmax) is associated with worse survival in stage III NSCLC, although a clear cutoff value for routine clinical use as a prognostic factor is uncertain at this time.

Detection of interval distant metastases: clinical utility of integrated CT-PET imaging in patients with esophageal carcinoma after neoadjuvant therapy.

The objective of the study was to determine the utility of integrated computed tomography / positron emission tomography (CT‐PET) imaging for detecting interval distant metastases and assessing therapeutic response in patients with locally advanced, potentially resectable esophageal carcinoma after neoadjuvant therapy.

Lung Cancer Epidemiology, Risk Factors, and Prevention

The greatest risk by far for developing lung cancer is cigarette smoking, but age, radon exposure, environmental pollution, occupational exposures, gender, race, and pre-existing lung disease also are important contributors. However, not all people with these risk factors develop lung cancer, and some without any known risk factor do, indicating the importance of genetic influences. Future advances in understanding and treating lung cancer will be based on genetic analysis. The most effective preventive measure is to never start or to stop cigarette smoking.