Correlation of molecular response as measured by 18-FDG positron emission tomography with outcome after chemoradiotherapy in patients with esophageal carcinoma

PURPOSE: To determine whether 18-fluorodeoxyglucose positron emission tomography (PET) computed tomography scans predict the pathologic complete response and disease-free and overall survival in patients with esophageal carcinoma undergoing definitive or preoperative chemoradiotherapy. METHODS AND MATERIALS: The records of patients with esophageal carcinoma presenting for definitive or preoperative treatment and undergoing pre- and post-treatment 18-fluorodeoxyglucose PET-computed tomography scans were retrospectively reviewed. The histologic type, T stage, and nodal status were the variables investigated to determine a relationship with the baseline standardized uptake value (SUV) of the primary tumor at diagnosis. We also attempted to determine whether a relationship exists between the percent decrease in SUV and a pathologic complete response, overall and disease-free survival. RESULTS: A total of 81 patients, 14 women and 67 men, underwent 18-fluorodeoxyglucose PET-computed tomography scanning before treatment and 63 also had post-treatment scans. T stage and tumor location predicted in univariate, but not multivariate, analysis for the initial SUV. Of the patients with a postchemoradiotherapy SUV of <2.5, 66% had tumor in the surgical specimen and 64% of patients had positive lymph nodes at surgery that were not imaged on the postchemoradiotherapy PET scan. A trend existed for post-treatment SUV and the days from radiotherapy to surgery to predict for a pathologic complete response (p = 0.09 and p = 0.08, respectively). The post-treatment SUV predicted for disease-free survival in the definitive chemoradiotherapy group (p = 0.01). CONCLUSIONS: A correlation was found between the depth of tumor invasion and the baseline SUV. The post-treatment SUV predicted for disease-free survival in the definitive chemoradiotherapy group. Caution should be exercised in using post-treatment PET scans to determine the necessity for surgical resection.     

Fractionated stereotactic body radiation therapy in the treatment of primary, recurrent, and metastatic lung tumors: the role of positron emission tomography/computed tomography-based treatment planning

PURPOSE: The aim of this study was to assess the outcomes of patients treated with stereotactic body radiation therapy (SBRT) in patients with primary, recurrent, or metastatic lung lesions, with a focus on positron emission tomography (PET)/computed tomography (CT)-based management. PATIENTS AND METHODS: Fifty-one patients with primary stage I non-small-cell lung cancer (NSCLC; n = 26), recurrent lung cancer after definitive treatment (n = 12), or solitary lung metastases (n = 13) were treated with SBRT between 2005 and 2007. Patients were treated with the CyberKnife Robotic Radiosurgery System with Synchrony respiratory tracking. A dose of 60 Gy was delivered in 3 fractions. All patients had CT or PET/CT performed at approximately 3-month intervals after treatment. RESULTS: The median follow-up was 12 months. Local control at median follow-up was 85% in patients with stage I NSCLC, 92% in patients with recurrent lung cancer, and 62% in the patients with solitary lung metastasis. Analysis of the 28 patients with pre- and post-treatment PET/CT scans demonstrated that those with stable disease (n = 4) had a mean standardized uptake value (SUV) decrease of 28%, partial responders (n = 11) had a decrease of 48%, and patients with a complete response (n = 11) had a decrease of 94%. Patients with progressive disease (n = 2) had an SUV decrease of only 0.4%. Only 2 patients (7%) who had reduced fluorodeoxyglucose avidity later progressed locally. No correlations were found between pretreatment SUV and tumor response, disease progression, or survival. Overall 1-year survival rates were 81%, 67%, and 85% among the patients with primary NSCLC, recurrent lung cancer, and solitary lung metastases, respectively. CONCLUSION: Stereotactic body radiation therapy with CyberKnife is an effective treatment for patients with medically inoperable recurrent or metastatic lung cancer. Positron emission tomography/CT is valuable in staging, planning, and evaluating treatment response and might predict long-term outcome.     

F-18 fluorodeoxyglucose positron emission tomography staging in radical radiotherapy candidates with nonsmall cell lung carcinoma: powerful correlation with survival and high impact on treatment

BACKGROUND: Successful treatment of nonsmall cell lung carcinoma (NSCLC) with radical radiotherapy (RT) requires accurate delineation of tumor extent. Conventional computed tomography-based noninvasive staging often estimates intrathoracic thoracic tumor extent incorrectly and fails to detect distant metastasis. High sensitivity and specificity are reported for F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) staging in potentially resectable NSCLC. The authors investigated FDG-PET staging in radical RT candidates with unresectable NSCLC. METHODS: The authors prospectively studied 153 consecutive patients with unresectable NSCLC who were candidates for radical RT after conventional staging and had PET scans. Patients were allocated both "before PET" and "after PET" stages. Subsequent management was recorded. Survival analysis was used to compare validity of pre-PET and post-PET staging. RESULTS: After PET, 107 patients (70%) actually received radical therapies (radical RT with or without concurrent chemotherapy, n = 102; radical surgery, n = 5); 46 patients (30%) received palliative treatment because of PET-detected distant metastasis (n = 28; 18%) or extensive locoregional disease (n = 18; 12%). Palliative therapies were RT (n = 33), chemotherapy (n = 12), or supportive care (n = 1). All five surgically treated patients underwent potentially curative resections after downstaging by PET. For radically treated patients, post-PET stage (P = 0.0041) but not pre-PET stage (P = 0.19) was strongly associated with survival. Radically treated patients survived longer than those treated palliatively (P = 0.02; 1-year survival, 69% and 44%, respectively; 2-year survival, 44% radical; no palliative patients had 2-yr follow-up). CONCLUSIONS: Positron emission tomography-assisted staging detected unsuspected metastasis in 20%, strongly influenced choice of treatment strategy, frequently impacted RT planning, and was a powerful predictor of survival. Potential impact of FDG-PET is even greater in radical RT candidates with NSCLC than in surgical candidates.     

Metabolic (FDG-PET) response after radical radiotherapy/chemoradiotherapy for non-small cell lung cancer correlates with patterns of failure

BACKGROUND: We previously reported that F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) response correlated strongly with survival after radical radiotherapy (RT)/chemoradiotherapy for non-small cell lung cancer (NSCLC). PET-response, survival and patterns of failure data are presented with long-term follow-up. METHODS: Pre- and post-treatment FDG-PET scans were performed for 88 patients after concurrent platinum-based radical chemo/RT (n = 73) or radical RT alone (n = 15). PET responses were prospectively assessed as either complete metabolic response (CMR), partial metabolic response (PMR), stable metabolic disease (SMD), or progressive metabolic disease (PMD). RESULTS: RT was 60 Gy in 30 fractions in 6 weeks. Follow-up PET was performed at a median of 70 days after treatment. PET responses were: CMR, n = 40 (45%); PMR, n = 32 (36%); SMD, n = 5 (6%) and PMD 11 (13%). Estimated median survival after follow-up PET was 23 months; median follow-up duration 35 months. One and 2 year survival after follow-up PET was 68% and 45%, respectively. Median survival for CMR and non-CMR patients was 31 and 11 months, respectively (p = 0.0001). One-year survival for CMR and non-CMR patients was 93% and 47%, respectively and 2 years survival was 62% and 30%, respectively. Excluding PMD patients, non-CMR patients had higher rates of local failure (HR 2.15, p = 0.009) and distant metastasis (HR 2.05, p = 0.041) than CMR patients. By last follow-up, 20 of 40 CR patients (50%) had PMD, with local failure (n = 8), distant metastasis (n = 2) or both (n = 10). CONCLUSIONS: Attainment of CMR after radical RT/chemoRT for NSCLC bestows superior freedom from local and distant relapse; late local relapse is common.     

Inadequacy of computed tomography in assessing patients with esophageal carcinoma after induction chemoradiotherapy

BACKGROUND: Induction chemoradiotherapy followed by surgery may improve survival of patients with esophageal carcinoma. Computed tomography (CT) has been used to evaluate the tumor response after completing induction chemoradiotherapy. The authors examined the ability of CT to evaluate the pathologic tumor response to induction therapy and to stage the tumor correctly. METHODS: Preinduction and postinduction chemoradiotherapy CT scans were reviewed retrospectively for 50 patients enrolled in a protocol of induction chemoradiotherapy followed by surgery. All studies were performed on third-generation or fourth-generation scanners. Radiographic response was determined using Eastern Cooperative Oncology Group solid tumor response criteria for bidimensional measurable disease. This was compared with the pathologic tumor response. CT-tumor (T) classification using the modified Tio scale was compared with the pathologic T classification. RESULTS: CT-T classification did not correlate with the pathologic stage (P = 0.09) or the pathologic tumor response (P = 0.22). The postinduction chemoradiotherapy CT accurately staged the T classification in 42% of patients but overstaged 36% of patients and understaged 20% of patients. CT had a sensitivity of 65%, a specificity of 33%, a positive predictive value of 58%, and a negative predictive value of 41% in evaluating the pathologic tumor response. CONCLUSIONS: CT is a poor diagnostic study tool for determining the pathologic tumor response or the pathologic disease stage after induction chemoradiotherapy in patients with esophageal carcinoma.     

Clinical outcome and predictors of survival and pneumonitis after stereotactic ablative radiotherapy for stage I non-small cell lung cancer

ABSTRACT: BACKGROUND: Stereotactic ablative radiotherapy (SABR) can achieve excellent local control rates in early-stage non-small cell lung cancer (NSCLC) and has emerged as a standard treatment option for patients who cannot undergo surgery or those with isolated recurrences. However, factors that may predict toxicity or survival are largely unknown. We sought here to identify predictors of survival and pneumonitis after SABR for NSCLC in a relatively large single-institution series. METHODS: Subjects were 130 patients with stage I NSCLC treated with four-dimensional computed tomography (4D CT) --planned, on-board volumetric image--guided SABR to 50 Gy in 4 fractions. Disease was staged by positron emission tomography/computed tomography (PET/CT) and scans were obtained again at the second follow-up after SABR. RESULTS: At a median follow-up time of 26 months, the 2-year local control rate was 98.5%. The median overall survival (OS) time was 60 months, and OS rates were 93.0% at 1 year, 78.2% at 2 years, and 65.3% at 3 years. No patient experienced grade 4--5 toxicity; 15 had radiation pneumonitis (12 [9.3%] grade 2 and 3 [2.3%] grade 3). Performance status, standardized uptake value (SUV)max on staging PET/CT, tumor histology, and disease operability were associated with OS on univariate analysis, but only staging SUVmax was independently predictive on multivariate analysis (P = 0.034). Dosimetric factors were associated with radiation pneumonitis on univariate analysis, but only mean ipsilateral lung dose >=9.14 Gy was significant on multivariate analysis (P = 0.005). CONCLUSIONS: OS and radiation pneumonitis after SABR for stage I NSCLC can be predicted by staging PET SUVmax and ipsilateral mean lung dose, respectively.     

FDG-PET-detected extracranial metastasis in patients with non-small cell lung cancer undergoing staging for surgery or radical radiotherapy--survival correlates with metastatic disease burden

The prognostic significance of extracranial distant metastasis detected by positron emission tomography (PET) was investigated in patients with non-small cell lung cancer (NSCLC). Forty-two patients staged with 18 F-fluorodeoxyglucose-PET-detected distant metastasis before planned surgery (n=7) or radical radiotherapy (RT)/chemoradiotherapy (n=35) for NSCLC were identified from a prospective database. The influence of metastasis number and other prognostic factors was investigated using Cox's regression analysis. Treatment after PET included surgery (n=2), radical RT (n =5), palliative RT (n=25), chemotherapy (n=8) or supportive care (n=2). All but 4 patients had died by the last follow-up. Median survival was 9 months overall, 12 months for 27 patients with single PET-detected metastasis and 5 months for 15 patients with >1 metastasis (p=0.009). It was found that the Eastern Cooperative Oncology Group performance status (p=0.027) but not pre-PET stage, weight loss or metastasis site correlated with survival. PET-detected metastatic tumor burden appeared to influence survival and should be evaluated as a prognostic factor in NSCLC.     

Prognostic relevance of response evaluation using [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography in patients with locally advanced non-small-cell lung cancer.

PURPOSE: The objective of this study was to determine the accuracy of (early) response measurements using [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography (18FDG PET) with respect to survival of patients with stage IIIA-N2 non-small-cell lung cancer (NSCLC) undergoing induction chemotherapy (IC), with a comparative analysis of PET methods. PATIENTS AND METHODS: In a prospective multicenter study, PET was performed in patients before IC and after one and three cycles. Computed tomography (CT) was performed before and after IC. Glucose consumption (metabolic rate of glucose [MRglu]) was measured using Patlak graphical analysis and correlated with simplified methods. Mediastinal lymph node (MLN) status was assessed visually. Cox proportional hazards analysis was used to determine the prognostic relevance of CT and PET measures of response with respect to survival. RESULTS: Complete PET data sets were available in 47 patients. Median survival was 21 months. MLN status after IC by PET predicted survival (hazard ratio [HR], 2.33; 95% CI, 1.04 to 5.22; P = .04) in contrast with CT (HR, 1.87; 95% CI, 0.81 to 4.30; P = .14). Residual MRglu after IC proved to be the best prognostic factor (HR, 1.95; 95% CI, 1.28 to 2.97; P = .002). Multivariate stepwise analysis showed that PET identified prognostically different strata in patients considered responsive according to CT. Residual MRglu after one cycle selected patients with different outcomes (HR, 2.04; 95% CI, 1.18 to 3.52; P = .01). Simplified quantitative 18FDG PET methods were correlated with Patlak graphical analysis during and after therapy (r > or = 0.90). CONCLUSION: 18FDG PET has additional value over CT in monitoring response to IC in patients with stage IIIA-N2 NSCLC, and it seems feasible to predict survival early during IC. Simple semiquantitative and complex PET methods perform equally well.     

Clinical impact of (18)F fluorodeoxyglucose positron emission tomography in patients with non-small-cell lung cancer: a prospective study.

PURPOSE: To prospectively study the impact of (18)F fluorodeoxyglucose (FDG) positron emission tomography (PET) on clinical management of patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: One hundred five consecutive patients with NSCLC undergoing (18)F FDG PET were analyzed. Before PET, referring physicians recorded scan indication, conventional clinical stage, and proposed treatment plan. PET scan results were reported in conjunction with available clinical and imaging data, including results of computed tomography (CT). Subsequent management and appropriateness of PET-induced changes were assessed by follow-up for at least 6 months or until the patient's death. RESULTS: Indications for PET were primary staging (n = 59), restaging (n = 34), and suspected malignancy subsequently proven to be NSCLC (n = 12). In 27 (26%) of 105 of cases, PET results led to a change from curative to palliative therapy by upstaging disease extent. Validity of the PET result was established in all but one case. PET appropriately downstaged 10 of 16 patients initially planned for palliative therapy, allowing either potentially curative treatment (four patients) or no treatment (six patients). PET influenced the radiation delivery in 22 (65%) of 34 patients who subsequently received radical radiotherapy. Twelve patients considered probably inoperable on conventional imaging studies were downstaged by PET and underwent potentially curative surgery. PET missed only one primary tumor (5-mm scar carcinoma). CT and PET understaged three of 20 surgical patients (two with N1 lesions < 5 mm and one with unrecognized atrial involvement), and PET missed one small intrapulmonary metastasis apparent on CT. No pathological N2 disease was missed on PET. CONCLUSION: FDG PET scanning changed or influenced management decisions in 70 patients (67%) with NSCLC. Patients were frequently spared unnecessary treatment, and management was more appropriately targeted.     

High rates of tumor growth and disease progression detected on serial pretreatment fluorodeoxyglucose‐positron emission tomography/computed tomography scans in radical radiotherapy candidates with nonsmall cell lung cancer

BACKGROUND:

The authors studied growth and progression of untreated nonsmall cell lung cancer (NSCLC) by comparing diagnostic and radiotherapy (RT) planning fluorodeoxyglucose (FDG)‐positron emission tomography (PET)/computed tomography (CT) scans before proposed radical chemo‐RT.

METHODS:

Patients enrolled on a prospective clinical trial were eligible for this analysis if they underwent 2 pretreatment whole body FDG‐PET/CT scans, >7 days apart. Scan 1 was performed for diagnosis/disease staging and scan 2 for RT planning. Interscan comparisons included disease stage, metabolic characteristics, tumor doubling times, and change in treatment intent.

RESULTS:

Eighty‐two patients underwent planning PET/CT scans between October 2004 and February 2007. Of these, 28 patients (61% stage III, 18% stage II) had undergone prior staging PET/CT scans. The median interscan period was 24 days (range, 8‐176 days). Interscan disease progression (TNM stage) was detected in 11 (39%) patients. The probability of upstaging within 24 days was calculated to be 32% (95% confidence interval [CI], 18%‐49%). Treatment intent changed from curative to palliative in 8 (29%) cases, in 7 because of PET. For 17 patients who underwent serial PET/CT scans under standardized conditions, there was a mean relative interscan increase of 19% in tumor maximum standardized uptake value (SUV) (P = .022), 16% in average SUV (P = .004), and 116% in percentage injected dose (P = .002). Estimated doubling time of FDG avid tumor was 66 days (95% CI, 51‐95 days).

CONCLUSIONS:

Rapid tumor progression was detected in patients with untreated, predominantly stage III, NSCLC on serial FDG‐PET/CT imaging, highlighting the need for prompt diagnosis, staging, and initiation of therapy in patients who are candidates for potentially curative therapy. Cancer 2010. © 2010 American Cancer Society.     

Impact of hybrid fluorodeoxyglucose positron-emission tomography/computed tomography on radiotherapy planning in esophageal and non-small-cell lung cancer

PURPOSE: The aim of this study was to investigate the impact of a hybrid fluorodeoxyglucose positron-emission tomography/computed tomography (FDG-PET/CT) scanner in radiotherapy planning for esophageal and non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: A total of 30 patients (16 with esophageal cancer, 14 with NSCLC) underwent an FDG-PET/CT for radiotherapy planning purposes. Noncontrast total-body spiral CT scans were obtained first, followed immediately by FDG-PET imaging which was automatically co-registered to the CT scan. A physician not involved in the patients' original treatment planning designed a gross tumor volume (GTV) based first on the CT dataset alone, while blinded to the FDG-PET dataset. Afterward, the physician designed a GTV based on the fused PET/CT dataset. To standardize PET GTV margin definition, background liver PET activity was standardized in all images. The CT-based and PET/CT-based GTVs were then quantitatively compared by way of an index of conformality, which is the ratio of the intersection of the two GTVs to their union. RESULTS: The mean index of conformality was 0.44 (range, 0.00-0.70) for patients with NSCLC and 0.46 (range, 0.13-0.80) for patients with esophageal cancer. In 10 of the 16 (62.5%) esophageal cancer patients, and in 12 of the 14 (85.7%) NSCLC patients, the addition of the FDG-PET data led to the definition of a smaller GTV. CONCLUSION: The incorporation of a hybrid FDG-PET/CT scanner had an impact on the radiotherapy planning of esophageal cancer and NSCLC. In future studies, we recommend adoption of a conformality index for a more comprehensive comparison of newer treatment planning imaging modalities to conventional options.     

The prognostic value of positron emission tomography in non-small cell lung cancer: analysis of 266 cases

Positron emission tomography (PET) is more accurate than computed tomography (CT) in the staging of non-small cell lung cancer (NSCLC). We analyzed the prognostic value of PET for survival in NSCLC patients. METHODS: Consecutive patients with proven NSCLC with PET for staging were selected. Staging by laboratory tests, bronchoscopy, chest X-ray, and CT was performed in all patients, leading to a clinical stage (c-TNM) prior to PET. A separate classification (pet-TNM) was obtained from PET images by observers blinded to clinical data. We performed univariate survival analysis with ECOG performance score, sex, weight loss, comorbidity, histology, c-TNM, and pet-TNM as variables. Cox regression analysis was performed with significant variables from the univariate analyses. RESULTS: Two hundred and sixty-six patients were included, 205 men and 61 women. c-TNM and pet-TNM were identical in 150 (56%) patients, 69 were upstaged, and 47 were downstaged by PET. At time of analysis, 198 (74%) patients had died. Univariate analysis showed significant survival differences for ECOG performance score (0 versus 1/2), weight loss (<10% versus >or=10%), pulmonary comorbidity, c-TNM, and pet-TNM (stage IA versus IB, IIA, IIB, IIIA, IIIB, IV). Cox regression analysis identified pet-TNM as the most significant (p < 0.001) prognostic factor, followed by ECOG performance score (p = 0.018). CONCLUSION: Tumor stage as determined by PET is the most significant prognostic factor for survival in patients with NSCLC.     

Predictive role of positron emission tomography (PET) in the outcome of lymphoma patients

An extensive analysis of the reliability of positron emission tomography (PET) after induction treatment in patients with Hodgkin's disease (HD) or aggressive non-Hodgkin's lymphoma (NHL). In all, 75 untreated patients with HD (n=41) or aggressive NHL (n=34) were studied with both PET and CT scans following standard chemotherapy induction therapy (ABVD or MACOP-B) with/without radiotherapy. Histopathological analysis was performed when considered necessary. After treatment, four out of five (80%) patients who were PET(+)/CT(-) relapsed, as compared with zero out of 29 patients in the PET(-)/CT(-) subset. Among the 41 CT(+) patients, 10 out of 11 (91%) who were PET(+) relapsed, as compared with 0 out of 30 who were PET(-). The actuarial relapse-free survival (RFS) rates were 9 and 100% in the PET(+) and PET(-) subsets, respectively (P=0.00001). All five patients who were PET(+)/CT(-) underwent a lymph node biopsy: in four (80%) cases, persistent lymphoma and was confirmed at histopathological examination. Two HD patients who were PET(-)/CT(+) (with large residual masses in the mediastinum or lung) were submitted to biopsy, which in both cases revealed only fibrosis. In HD and aggressive NHL patients, PET positivity after induction treatment is highly predictive for the presence of residual disease, with significant differences being observable in terms of RFS. PET negativity at restaging strongly suggests the absence of active disease; histopathological verification is important in patients who show PET positivity.     

基于CT或PET/CT的影像组学信息预测Ⅰ期非小细胞肺癌立体定向消融放疗疗效的初步研究

背景与目的:影像组学作为极具潜力的新领域,是指从影像图像中提取有价值的图像特征,并将这些特征数据定量化并转换成可挖掘的数据矿用以指导临床.该回顾性研究应用影像组学的方法初步探索PET/CT对比常规CT在Ⅰ期非小细胞肺癌(non-small cell lung cancer,NSCLC)患者接受立体定向消融放疗(stereotactic ablative radiotherapy,SABR)后疗效预测方面的可行性.方法:回顾性收集经病理证实并在复旦大学附属肿瘤医院行SABR治疗的Ⅰ期NSCLC患者,提取治疗前PET/CT和定位CT图像,由放疗科医师勾画病灶,运用影像组学的方法进行特征值的提取、分析和总结,采用NMF聚类法(non-negative matrix factorization)分析这些特征值是否能够对有无局部进展的患者进行区分,所有统计学算法都在R平台(R Development Core Team)上实现.结果:16例患者纳入最终分析,在PET/CT的影像组学PET特征中发现两个差异有统计学意义的特征值(灰度共生矩阵最大相关系数和灰度游程共生矩阵长行程加重),可以用以区分患者是否出现局部进展,而在所有定位CT图像提取的特征值中并没有类似发现.结论:在经过SABR治疗后的Ⅰ期NSCLC患者中应用基线PET/CT及胸部定位CT提供的信息进行影像组学分析后,PET/CT似乎能够提供更具统计效能的PET特征值用以预测疗效,对比胸部定位CT提供的信息,PET/CT所提取的特征值可能更敏感、更全面甚至更具特征性.     

The role of positron emission tomography in evaluating mediastinal lymph node metastases in non-small-cell lung cancer

Positron emission tomography (PET) is a modality that differentiates malignant from benign processes based upon metabolism rather than anatomy. A number of studies have confirmed improved accuracy of PET over computed tomography (CT), but until a few recent studies, most had failed to include satisfactory histologic confirmation. The objective of this study was to compare PET and CT to histologic staging of the mediastinum in patients with non-small-cell lung cancer (NSCLC). Histologic examination of mediastinal lymph nodes (MLNs) was performed on 40 patients with NSCLC at mediastinoscopy and/or at surgical resection. PET scans were interpreted by one of two nuclear medicine physicians, blinded to histology, using CT scans for anatomic localization. CT scans were independently evaluated for mediastinal lymphadenopathy. The overall accuracy, sensitivity, and specificity of PET were 78% (31 of 40), 67% (four of six), and 79% (27 of 34), respectively. The overall accuracy, sensitivity, and specificity of CT were 68% (27 of 40), 50% (three of six), and 71% (24 of 34), respectively. PET was superior to CT at correctly identifying mediastinal nodal metastases; however, both modalities were inferior to the gold standard of surgical staging. PET is more accurate than CT in staging the mediastinum of patients with NSCLC. PET failed to identify lymph node metastasis in 33% of patients with histologically proven MLN involvement, and false positives were present in 15%. At present, mediastinoscopy should remain the standard of care for preoperative mediastinal staging for NSCLC.     

Functional polymorphisms of the microsomal epoxide hydrolase gene: a reappraisal on a early-onset lung cancer patients series

As concomitant chemoradiotherapy for stage III NSCLC is associated with survival advantage in comparison to a sequential approach, we conducted a phase III randomised study aiming to determine the best sequence and safety of chemotherapy (CT) and chemoradiotherapy (CT-RT), using a regimen with cisplatin (CDDP), gemcitabine (GEM) and vinorelbine (VNR). Unresectable stage III NSCLC patients received CDDP (60 mg/m(2)), GEM (1g/m(2), days 1 and 8) and VNR (25mg/m(2), days 1 and 8) with reduced dosage of GEM and VNR during radiotherapy (66Gy). Two cycles of CT with radiotherapy followed by two further cycles of CT alone were administered in arm A or the reverse sequence in arm B. The study was prematurely closed for poor accrual due to administrative problems. Forty-nine eligible patients were randomised. Response rates and median survival times were, respectively 57% (95% CI: 36-78%) and 17 months (95% CI: 9.3-24.6 months) in arm A and 79% (95% CI: 64-94%) and 23.9 months (95% CI: 13.3-34.5 months) in arm B (p>0.05). Chemotherapy dose-intensity was significantly reduced in arm A. Grade 3-4 oesophagitis occurred in 5 patients. One case of grade 5 radiation pneumonitis was observed. In conclusion, chemoradiotherapy with CDDP, GEM and VNR appears feasible as initial treatment or after induction chemotherapy. Consolidation chemoradiotherapy seems less toxic with a better observed response rates and survival although no valid conclusion can be drawn from the comparison of both arms.     

Impact of positron emission tomography/computed tomography surveillance at 12 and 24 months for detecting head and neck cancer recurrence

BACKGROUND:

In head and neck cancer (HNC), 3‐month post‐treatment positron emission tomography (PET)/computed tomography (CT) reliably identifies persistent/recurrent disease. However, further PET/CT surveillance has unclear benefit. The impact of post‐treatment PET/CT surveillance on outcomes is assessed at 12 and 24 months.

METHODS:

A 10‐year retrospective analysis of HNC patients was carried out with long‐term serial imaging. Imaging at 3 months included either PET/CT or magnetic resonance imaging, with all subsequent imaging comprised of PET/CT. PET/CT scans at 12 and 24 months were evaluated only if preceding interval scans were negative. Of 1114 identified patients, 284 had 3‐month scans, 175 had 3‐ and 12‐month scans, and 77 had 3‐, 12‐, and 24‐month scans.

RESULTS:

PET/CT detection rates in clinically occult patients were 9% (15 of 175) at 12 months, and 4% (3 of 77) at 24 months. No difference in outcomes was identified between PET/CT‐detected and clinically detected recurrences, with similar 3‐year disease‐free survival (41% vs 46%, P = .91) and 3‐year overall survival (60% vs 54%, P = .70) rates. Compared with 3‐month PET/CT, 12‐month PET/CT demonstrated fewer equivocal reads (26% vs 10%, P < .001). Of scans deemed equivocal, 6% (5 of 89) were ultimately found to be positive.

CONCLUSIONS:

HNC patients with negative 3‐month imaging appear to derive limited benefit from subsequent PET/CT surveillance. No survival differences were observed between PET/CT‐detected and clinically detected recurrences, although larger prospective studies are needed for further investigation. Cancer 2013. © 2012 American Cancer Society.     

Clinical observation of platinum-based combined with concurrent three-dimensional conformal radiotherapy in patients with locally advanced non-small cell lung cancer

Objective:The aim of our study was to explore the short-term ef icacy of platinum-based combined with concur-rent chemoradiotherapy for local y advanced non-smal-celllung cancer (NSCLC). Methods:Between 2006 to 2010, 78 cases of local y advanced NSCLC were enrol ed into this trial. Al patients were given platinum-based chemotherapy combined with concurrent three-dimensional conformal radiotherapy (3-DCRT). Chest CT scans were obtained during end-expiratory and end-inspiratory pauses when performing positioning. Image fusion was done after the image data was transferred to treat-ment plan system (TPS). The target volume was delineated on the fusion images. The chemotherapy was given on the first day of radiotherapy. Comprehensive examinations were conducted 4-6 weeks after concurrent chemoradiotherapy to assess short-term ef icacy. Results:Complete remission (CR) was achieved in 8 cases and partial remission (PR) in 54 cases. The ef iciency rate reached 79.5%. Grade III-IV radiation esophagitis occurred in 11.5%. No exit and death cases during treat-ment. Conclusion:Concurrent chemo-radiotherapy could significantly improve the short-term ef icacy and prolong survival of stage III NSCLC, meanwhile the adverse reactions could be tolerated.     

Clinical implications of defining the gross tumor volume with combination of CT and 18FDG-positron emission tomography in non-small-cell lung cancer

PURPOSE: To compare the planning target volume (PTV) definitions for computed tomography (CT) vs. positron emission tomography (PET) in non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: A total of 21 patients with NSCLC underwent three-dimensional conformal radiotherapy planning. All underwent a staging F-18 fluorodeoxyglucose-position emission tomography (18FDG-PET) scan and underwent treatment simulation using CT plus a separate planning 18FDG-PET scan. Three sets of target volumes were defined: Set 1, CT volumes (CT tumor + staging PET nodal disease); Set 2, PET volumes (planning PET tumor {gross tumor volume (GTV) = [(0.3069 x mean standardized uptake value) + 0.5853])}; Set 3, composite CT-PET volumes (fused CT-PET tumor). Sets 1 and 2 were compared using a matching index. Three-dimensional conformal radiotherapy plans were created using the Set 1 (CT) volumes; and coverage of the Set 3 (composite) volumes was evaluated. Separate three-dimensional conformal radiotherapy plans were designed for the Set 3 volumes. RESULTS: For the primary tumor GTV, the Set 1 (CT) volume was larger than the Set 2 (PET) volume in 48%, smaller in 33%, and equal in 19%. The mean matching index was 0.65 (35% CT-PET mismatch). Although quantitatively similar, the volumes differed qualitatively. The Set 3 (composite) volume was larger than either CT or PET alone in 62%, smaller in 24%, and equal in 14%. The dose-volume histogram parameters did not differ among the plans for Set 1 (CT) vs. Set 3 (composite) volumes. Small portions of the Set 3 PTV were significantly underdosed in 40% of cases using the CT-only plan. CONCLUSION: Computed tomography and PET are complementary and should be obtained in the treatment position and fused to define the GTV for NSCLC. Although the quantitative absolute target volume is sometimes similar, the qualitative target locations can be substantially different, leading to underdosage of the target when planning is done using CT alone without PET fusion.     

Prognostic effect of incongruous lymph node status in early-stage non-small cell lung cancer

IntroductionTumor recurrence is an important issue for patients with stage I non-small cell lung cancer (NSCLC) and adjuvant therapy is considered of no benefit to a tumor less than 4 cm. The purpose of this study was to evaluate the impact of positron emission tomography/computed tomography (PET/CT) on tumor recurrence in patients with a completely resected pN0 NSCLC less than 4 cm.MethodsBetween January 2011 and December 2016, 211 consecutive patients with diagnoses of stage I NSCLC less than 4 cm after complete resection were included. The maximum of standard uptake value (SUVmax) of primary tumor and the presence of positive lymph nodes on PET/CT scans were documented. Disease-free survival was evaluated by the Kaplan-Meier method and recurrence risk factors were identified by univariable and multivariable analyses.ResultsPatients with positive lymph nodes on PET/CT had a lower 5-year disease-free survival (37.6% vs 72.7%, p < 0.001). Multivariable analysis demonstrated that the tumor SUVmax >2.93, the presence of positive lymph nodes on PET/CT, and poor differentiation were significant factors for tumor recurrence. Patients with the tumor SUVmax >2.93 and positive lymph nodes on PET/CT simultaneously had 5.33-fold increase in the risk of recurrence (p < 0.001).ConclusionThe presence of positive lymph nodes on PET/CT scans can be a good indicator in predicting patients with high risk of developing recurrence in pN0 NSCLC less than 4 cm. This result helps identify patients likely to benefit from adjuvant therapy.