ABSTRACT
Despite recent improvements to current therapies and the emergence of novel agents to manage advanced non-small cell lung cancer (NSCLC), the patients' overall survival remains poor. Re-challenging with first-line chemotherapy upon relapse is common in the management of small cell lung cancer but is not well reported for advanced NSCLC. NSCLC relapse has been attributed to acquired drug resistance, but the repopulation of sensitive clones may also play a role, in which case re-challenge may be appropriate. Here, we report the results of re-challenge with gemcitabine plus carboplatin in 22 patients from a single institution who had previously received gemcitabine plus platinum in the first-line setting and had either partial response or a progression-free interval of longer than 6 months. In this retrospective study, the charts of patients who underwent second-line chemotherapy for NSCLC in our cancer center between January 2005 and April 2010 were reviewed. All the patients who received a combination of gemcitabine and carboplatin for re-challenge were included in the study. These patients were offered second-line treatment on confirmation of clear radiological disease progression. The overall response rate was 15% and disease control rate was 75%. The median survival time was 10.4 months, with 46% of patients alive at 1 year. These results suggest that re-challenge chemotherapy should be considered in selected patients with radiological partial response or a progression-free survival of longer than 6 months to the initial therapy.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Carboplatin/administration & dosage , Carcinoma, Non-Small-Cell Lung/pathology , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Disease Progression , Disease-Free Survival , Female , Follow-Up Studies , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Remission Induction , Retrospective Studies , Survival Rate , GemcitabineABSTRACT
PURPOSE: (18)F-Fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) has benefits in target volume (TV) definition in radiotherapy treatment planning (RTP) for non-small-cell lung cancer (NSCLC); however, an optimal protocol for TV delineation has not been determined. We investigate volumetric and positional variation in gross tumor volume (GTV) delineation using a planning PET/CT among three radiation oncologists and a PET radiologist. METHODS AND MATERIALS: RTP PET/CT scans were performed on 28 NSCLC patients (Stage IA-IIIB) of which 14 patients received prior induction chemotherapy. Three radiation oncologists and one PET radiologist working with a fourth radiation oncologist independently delineated the GTV on CT alone (GTV(CT)) and on fused PET/CT images (GTV(PETCT)). The mean percentage volume change (PVC) between GTV(CT) and GTV(PETCT) for the radiation oncologists and the PVC between GTV(CT) and GTV(PETCT) for the PET radiologist were compared using the Wilcoxon signed-rank test. Concordance index (CI) was used to assess both positional and volume change between GTV(CT) and GTV(PETCT) in a single measurement. RESULTS: For all patients, a significant difference in PVC from GTV(CT) to GTV(PETCT) exists between the radiation oncologist (median, 5.9%), and the PET radiologist (median, -0.4%, p = 0.001). However, no significant difference in median concordance index (comparing GTV(CT) and GTV(FUSED) for individual cases) was observed (PET radiologist = 0.73; radiation oncologists = 0.66; p = 0.088). CONCLUSIONS: Percentage volume changes from GTV(CT) to GTV(PETCT) were lower for the PET radiologist than for the radiation oncologists, suggesting a lower impact of PET/CT in TV delineation for the PET radiologist than for the oncologists. Guidelines are needed to standardize the use of PET/CT for TV delineation in RTP.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Positron-Emission Tomography , Radiation Oncology , Tumor Burden , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/radiotherapy , Female , Fluorodeoxyglucose F18 , Humans , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Lung Neoplasms/radiotherapy , Male , Middle Aged , Neoplasm Staging , Positron-Emission Tomography/methods , Radiopharmaceuticals , Remission Induction , Statistics, Nonparametric , Tomography, X-Ray Computed/methodsABSTRACT
PURPOSE: Positron emission tomography (PET), in addition to computed tomography (CT), has an effect in target volume definition for radical radiotherapy (RT) for non-small-cell lung cancer (NSCLC). In previously PET-CT staged patients with NSCLC, we assessed the effect of using an additional planning PET-CT scan for gross tumor volume (GTV) definition. METHODS AND MATERIALS: A total of 28 patients with Stage IA-IIIB NSCLC were enrolled. All patients had undergone staging PET-CT to ensure suitability for radical RT. Of the 28 patients, 14 received induction chemotherapy. In place of a RT planning CT scan, patients underwent scanning on a PET-CT scanner. In a virtual planning study, four oncologists independently delineated the GTV on the CT scan alone and then on the PET-CT scan. Intraobserver and interobserver variability were assessed using the concordance index (CI), and the results were compared using the Wilcoxon signed ranks test. RESULTS: PET-CT improved the CI between observers when defining the GTV using the PET-CT images compared with using CT alone for matched cases (median CI, 0.57 for CT and 0.64 for PET-CT, p = .032). The median of the mean percentage of volume change from GTV(CT) to GTV(FUSED) was -5.21% for the induction chemotherapy group and 18.88% for the RT-alone group. Using the Mann-Whitney U test, this was significantly different (p = .001). CONCLUSION: PET-CT RT planning scan, in addition to a staging PET-CT scan, reduces interobserver variability in GTV definition for NSCLC. The GTV size with PET-CT compared with CT in the RT-alone group increased and was reduced in the induction chemotherapy group.
Subject(s)
Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Lung Neoplasms/diagnostic imaging , Positron-Emission Tomography/methods , Tomography, X-Ray Computed/methods , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/radiotherapy , Carcinoma, Squamous Cell/diagnostic imaging , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/radiotherapy , Female , Fluorodeoxyglucose F18 , Humans , Lung Neoplasms/pathology , Lung Neoplasms/radiotherapy , Male , Middle Aged , Neoplasm Staging/methods , Observer Variation , Radiopharmaceuticals , Radiotherapy Planning, Computer-Assisted/methods , Remission Induction , Tumor BurdenABSTRACT
PURPOSE: To investigate whether failure to suppress the prostate-specific antigen (PSA) level to Subject(s)
Gonadotropin-Releasing Hormone/agonists
, Prostate-Specific Antigen/blood
, Prostatic Neoplasms/blood
, Prostatic Neoplasms/therapy
, Aged
, Aged, 80 and over
, Androgen Antagonists/therapeutic use
, Follow-Up Studies
, Humans
, Male
, Middle Aged
, Neoadjuvant Therapy/methods
, Prostatic Neoplasms/mortality
, Prostatic Neoplasms/pathology
, Radiotherapy, Conformal
, Reference Values
, Retrospective Studies
, Survival Rate