Positron emission tomographic scanning in the diagnosis and staging of non-small cell lung cancer 2 cm in size or less.

OBJECTIVE: Several studies have suggested that positron emission tomography is more accurate than computed tomography for the staging of non-small cell lung cancer and can reduce the rate of unnecessary thoracotomy in patients with potentially resectable disease. However, there are few data on the utility of positron emission tomography in the diagnosis of patients with tumors of 2 cm or less in size. METHODS: Patients with cT1/cT2 tumors of 2 cm or less in size were retrospectively reviewed. All had a computed tomographic scan, as well as a positron emission tomographic scan on a dedicated scanner, with a standard uptake value reported. A standard uptake value of 2.5 g/mL or greater was considered positive. The results of computed tomography and positron emission tomography were correlated with pathologic results after either resection (n = 60) or mediastinoscopy (n = 4). RESULTS: Sixty-four patients (38 women; mean age, 66 years) had a mean tumor size of 1.4 cm (range, 0.7-2.0 cm). Forty-three patients had adenocarcinoma, 13 had adenocarcinoma-bronchioloalveolar carcinoma, 5 had squamous cell carcinoma, and 3 had other tumor types. Twenty-nine (45%) tumors had negative positron emission tomographic results. Both tumor size (>1 cm vs < or =1 cm) and cell type (adenocarcinoma-bronchioloalveolar carcinoma vs all other cell types) were significant predictors of positron emission tomography uptake in the primary tumor (P = .05 and .01, respectively). Nodal metastases were detected pathologically in 11 (17%) patients (5 N1 and 6 N2). Positron emission tomographic sensitivity and specificity for nodal metastases were only 45% and 89%, respectively. There was no statistically demonstrable survival difference between positron emission tomography-positive and positron emission tomography-negative tumors (3-year survival of 87% vs 100%, respectively). CONCLUSION: Positron emission tomographic scanning has no demonstrable benefit in the diagnosis, staging, or prognosis of patients with tumors of 2 cm or less in size.

Tumor size is a determinant of stage distribution in t1 non-small cell lung cancer.

STUDY OBJECTIVE: Despite renewed interest in early detection of lung cancer, the relationship between tumor size and survival remains controversial. The objective of this study was to evaluate the relationship between size and stage in patients with T1 (< or = 3.0 cm) non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: A retrospective review of a lung cancer database from 1995 to 2003 identified 503 patients with completely resected invasive NSCLC with tumors < or = 3 cm. All clinical and pathologic characteristics were recorded. Univariate associations between nodal status and other prognostic factors were explored by chi2 and t tests. The independent effect of tumor size > 2 cm vs < or = 2 cm on the risk of nodal disease was analyzed using a logistic regression model. RESULTS: Of the 503 patients, 324 patients (64.4%) had stage IA disease, 52 patients (10.3%) had stage IB disease, 37 patients (7.4%) had stage IIA disease, 15 patients (3%) had stage IIB disease, 43 patients (8.6%) had stage IIIA disease, 24 patients (4.8%) had stage IIIB disease, and 8 patients (1.6%) had stage IV disease. One hundred patients (19.9%) had nodal metastases. The mean (+/- SD) tumor size of cases without nodal disease was 1.90 +/- 0.67 cm, compared to 2.18 +/- 0.69 cm for node-positive tumors (p = 0.0003; 95% confidence interval [CI] for mean difference, 0.13 to 0.43). Forty-eight of 308 patients (15.6%) with smaller carcinomas (< or = 2.0 cm) compared to 52 of 195 patients (26.7%) with carcinomas > 2.0 cm had nodal metastases (p = 0.002). Exploratory multivariate analysis revealed that only tumor size (< or = 2.0 cm [referent] vs > 2.0 cm) affected nodal status and thus stage (adjusted odds ratio, 2.0; 95% CI, 1.3 to 3.1; p = 0.002). CONCLUSIONS: Primary invasive NSCLC > 2.0 cm was twice as likely to have nodal metastases than carcinomas < or = 2.0 cm. Our results suggest that in lung cancer smaller lesions may represent earlier stage disease. These results also suggest the need for further subclassification by tumor size within the current International Union Against Cancer/American Joint Committee on Cancer stage I, with tumors < 2 cm in size contained in a separate substage. This refinement may help to better clarify which patients might benefit from novel adjuvant or neoadjuvant therapeutic interventions.

Surgical resection for residual N2 disease after induction chemotherapy.

BACKGROUND: Induction therapy is a common treatment modality for patients with stage IIIA non-small cell lung cancer (NSCLC). Although mediastinal nodal downstaging after induction therapy is generally considered a favorable prognostic feature, the benefit of resection in the presence of residual N2 disease is controversial. In this study we analyzed our experience with resection after induction chemotherapy in patients with residual N2 disease to more precisely define the role of surgical resection in this group of patients. METHODS: In this retrospective analysis, we reviewed the records of 78 patients with N2 disease who received induction therapy with preoperative intent between 1990 and 2003. All patients had potentially resectable disease. Survival analysis was performed using the Kaplan-Meier method. A Cox proportional hazards regression model was used to evaluate multiple prognostic factors. RESULTS: There were 78 patients (39 men) with a median age of 64 years. Sixty had nonsquamous histology. Resection was performed in 52 patients (47 R0). Hospital mortality was 1.9%. A complete pathologic response occurred in 2 of 52 (3.8%) patients and 19 of 52 (36%) patients had no residual N2 disease. Overall 5-year survival for resected patients was 23%. Overall 5-year survival was 30% for N0-N1 patients and 19% for those with residual N2 disease. Multivariable analysis identified clinical response to therapy (p = 0.0007) and histology (p = 0.01), but not residual N2 disease (p = 0.65), as important prognostic variables. CONCLUSIONS: Surgical resection may be a viable option for patients with residual N2 disease after induction chemotherapy, provided an R0 resection can be performed.

Reduced frontal white matter integrity in early-onset schizophrenia: a preliminary study.

BACKGROUND: Research suggests that brain frontal white matter (WM) might be qualitatively altered in adolescents with early onset schizophrenia (EOS). Diffusion tensor imaging provides a relatively new approach for quantifying possible connectivity of WM in vivo. METHODS: Diffusion tensor imaging was used to examine the WM integrity of frontal regions at seven levels from 25 mm above to 5 mm below the anterior commissure-posterior commissure (AC-PC) plane. Three other regions were examined: the occipital region at the AC-PC plane and the genu and splenium of the corpus callosum. Fractional anisotropy was compared between 12 adolescents (nine male, 3 female) with EOS (onset of psychotic symptoms by age 18 years) and nine age-similar healthy comparison subjects (six male, 3 female). RESULTS: Adolescents with EOS had significantly reduced fractional anisotropy in the frontal WM at the AC-PC plane in both hemispheres and in the occipital WM at the AC-PC plane in the right hemisphere. CONCLUSIONS: These preliminary data support a hypothesis that alterations in brain WM integrity occur in adolescents with EOS. Abnormalities found in this study were similar to those reported in adults with chronic schizophrenia. Additional studies are needed to assess whether there is progression of WM abnormalities in schizophrenia.

Pain measurement with evoked potentials: combination of subjective ratings, randomized intensities, and long interstimulus intervals produces a P300-like confound.

Evoked potentials in response to painful stimuli have been studied as objective measures of pain. Bromm has advocated experimental conditions in which, (1) stimulus intensities are randomized, and (2) subjects rate each stimulus. However, a cognitive, i.e. information processing, 'late positive component' (LPC), e.g. the P300, may be elicited by these same conditions, whether or not the stimuli are painful. The LPC may overlap, and interfere with the measurement of, responses that are only seen with painful stimuli. We compared the LPC in two experimental protocols using ten subjects and electrical stimuli. In the 'Rating Protocol', shocks of different intensity levels were randomly presented and subjects rated the intensity of each stimulus. In the 'Oddball Standards Protocol', the same levels were used, but each was presented in a separate block of a single level. Stimuli were presented more rapidly and subjects had to push a button in response to occasional double shocks (oddball targets), but not to single shocks (oddball standards). The oddball targets served to direct subjects' attention to the stimuli, but only the evoked potential responses to the oddball standards were used for data analysis. To look at the difference between protocols, we computed a difference condition (Rating protocol responses minus Oddball Standards protocol responses) which we called Incremental activity. The Incremental LPC (average amplitudes from 350 to 650 ms) had a more parietal topography (amplitude at electrode Pz greater than at Cz) than the Oddball Standards LPC (Cz > Pz; protocol x electrode interaction P<0.001). This implies that the Rating Protocol LPC included P300-like activity. The parietal Incremental activity began as early as 250-350 ms after the stimulus in the responses to the most painful stimuli and therefore can confound the measurement of pain activity in the evoked potential.