Prognostic stratification of stage IIIA-N2 non-small-cell lung cancer after induction chemotherapy: a model based on the combination of morphometric-pathologic response in mediastinal nodes and primary tumor response on serial 18-fluoro-2-deoxy-glucose positron emission tomography

Early radiologic and metabolic tumour response assessment during combined chemo-radiotherapy for locally advanced NSCLC

Background

The role of early treatment response for patients with locally advanced non-small cell lung cancer (LA-NSCLC) treated with concurrent chemo-radiotherapy (cCRT) is unclear. The study aims to investigate the predictive value of response to induction chemotherapy (iCX) and the correlation with pattern of failure (PoF).

Materials and methods

Patients with LA-NSCLC treated with cCRT were included for analyses (n = 276). Target delineations were registered from radiotherapy planning PET/CT to diagnostic PET/CT, in between which patients received iCX. Volume, sphericity, and SUVpeak were extracted from each scan. First site of failure was categorised as loco-regional (LR), distant (DM), or simultaneous LR+M (LR+M). Fine and Gray models for PoF were performed: a baseline model (including performance status (PS), stage, and histology), an image model for squamous cell carcinoma (SCC), and an image model for non-SCC. Parameters included PS, volume (VOL) of tumour, VOL of lymph nodes, ΔVOL, sphericity, SUVpeak, ΔSUVpeak, and oligometastatic disease.

Results

Median follow-up was 7.6 years. SCC had higher sub-distribution hazard ratio (sHR) for LRF (sHR = 2.771 [1.577:4.87], p < 0.01) and decreased sHR for DM (sHR = 0.247 [0.125:0.485], p  <  0.01). For both image models, high diagnostic SUVpeak increased risk of LRF (sHR = 1.059 [1.05:1.106], p < 0.01 for SCC, sHR = 1.12 [1.03:1.21], p < 0.01 for non-SCC). Patients with SCC and less decrease in VOL had higher sHR for DM (sHR = 1.025[1.001:1.048] pr. % increase, p = 0.038).

Conclusion

Poor response in disease volume was correlated with higher sHR of DM for SCC, no other clear correlation of response and PoF was observed. Histology significantly correlated with PoF with SCC prone to LRF and non-SCC prone to DM as first site of failure. High SUVpeak at diagnosis increased the risk of LRF for both histologies.

Pathologic Processing of Lung Cancer Resection Specimens After Neoadjuvant Therapy

Neoadjuvant treatment of non-small cell lung cancer challenges the traditional processing of pathology specimens. Induction therapy before resection allows evaluation of the efficacy of neoadjuvant agents at the time of surgery. Many clinical trials use pathologic tumor response, measured as major pathologic response (MPR, ≤10% residual viable tumor [RVT]) or complete pathologic response (CPR, 0% RVT) as a surrogate of clinical efficacy. Consequently, accurate pathologic evaluation of RVT is crucial. However, pathologic assessment has not been uniform, which is particularly true for sampling of the primary tumor, which instead of the traditional processing, requires different tissue submission because the focus has shifted from tumor typing alone to RVT scoring. Using a simulation study, we analyzed the accuracy rates of %RVT, MPR, and CPR of 31 pretreated primary lung tumors using traditional grossing compared with the gold standard of submitting the entire residual primary tumor and identified the minimum number of tumor sections to be submitted to ensure the most accurate scoring of %RVT, MPR, and CPR. Accurate %RVT, MPR, and CPR calls were achieved in 52%, 87%, and 81% of cases, respectively, using the traditional grossing method. Accuracy rates of at least 90% for these parameters require either submission of all residual primary tumor or at least 20 tumor sections. Accurate %RVT, MPR, and CPR scores cannot be achieved with traditional tumor grossing. Submission of the entire primary tumor, up to a maximum of 20 sections, is required for the most accurate reads.

Treatment Sequencing in Resectable Lung Cancer: The Good and the Bad of Adjuvant Versus Neoadjuvant Therapy

The treatment scenario for patients with resectable non-small cell lung cancer has changed dramatically with the incorporation of immunotherapy. The introduction of immunotherapy into treatment algorithms has yielded improved clinical outcomes in several phase II and III trials in both adjuvant (Impower010 and PEARLS) and neoadjuvant settings (JHU/MSK, LCMC3, NEOSTAR, Columbia/MGH, NADIM, and CheckMate-816), leading to new U.S. Food and Drug Administration approvals in this sense. Different treatment options are now available for patients, making the optimal treatment scenario a matter of intense debate. In this review, we summarize the main results concerning treatment sequencing in resectable non-small cell lung cancer from the past 30 years in the preimmunotherapy era, focusing on recent advances after incorporation of immunotherapy. Finally, the utility of several parameters (PD-L1, tumor mutational burden, radiomics, circulating tumor DNA, T-cell receptor, and immune populations) as predictive biomarkers for therapy personalization is discussed.

Survival Analysis of Surgically Resected ypN2 Lung Cancer after Neoadjuvant Therapy

INTRODUCTION

 Surgery is widely accepted today when downstaging of mediastinal lymph nodes after neoadjuvant therapy is achieved. However, the role of surgery in patients with persistent N2 disease is still controversial. This study aims to detail the diagnostic problems, prognostic features, and long-term survival of the persistent N2 non-small cell lung cancer patient group.

PATIENTS AND METHODS

 One-hundred fifty patients who received neoadjuvant therapy and subsequently underwent resection, in-between 2003 and 2015, were retrospectively analyzed. In this study, "persistent N2" group refers to patients who received neoadjuvant therapy for clinically or histologically proven N2, who underwent a surgery after having been classified as "downstaged" at restaging, but in whom ypN2 lesions were subsequently confirmed on the operative specimens. Patients with multistation N2 were included in the study. There were 119 patients who met the criteria, whereas persistent ypN2 was detected in 28.5% (n = 34) of all patients.

RESULTS

 Overall 5-year survival rate was 47.2%, while it was 23.4% for patients with persistent N2. Factors that adversely affected survival were to have nonsquamous cell histological type (p = 0.006), high ypT stage (p = 0.001), persistent N2 (p = 0.02), and recurrence during follow-up (p < 0.001). A trend toward a shorter survival was observed when the ypN2 zone was subcarinal versus other zones, but did not reach statistical significance (p = 0.08). In addition, a trend toward a shorter survival of patients with multiple N2 involvement (p = 0.412) was observed.

CONCLUSION

 In the persistent N2 group, when multiple involvement or subcarinal involvement was excluded, relatively good survival was detected.

A narrative review of primary research endpoints of neoadjuvant therapy for lung cancer: past, present and future

Objective

This review summarizes the current status of neoadjuvant therapy and discusses the choice of new clinical research endpoints for non-small cell lung cancer.

Background

Neoadjuvant chemotherapy is a recognized practice in patients with resectable and locally advanced lung cancer. With the introduction of molecular targeted drugs and immune checkpoint inhibitors (ICIs), the overall survival (OS) of patients with lung cancer has been significantly improved, and the original traditional clinical research endpoints are no longer suitable for existing clinical research. In order to accelerate the process of clinical trials and the development and approval of drugs, it is necessary to find suitable alternative indicators as the main indicators of clinical research.

Methods

Therefore, this article focuses on clinical trials using disease-free survival (DFS), progression free survival, and pathological evaluation indicators, pathologic complete response and major pathologic response, as surrogate endpoints. We search related literature through PubMed database and clinical trials through clinicaltrials.gov.

Conclusions

Pathologic complete response and major pathologic response are recommended as surrogate endpoints in the era of neoadjuvant immunotherapy, and secondary endpoints are listed for the prediction of pathological results. In addition, the definitions of major pathological response (MPR) and PCR should be standardized, and a new pathological evaluation standard should be developed, which is applicable to all current treatment methods.

Keywords

Neoadjuvant therapy; resectable lung cancer; clinical research endpoint; pathological response.

Update on Molecular Imaging and Precision Medicine in Lung Cancer

Precision medicine integrates molecular pathobiology, genetic make-up, and clinical manifestations of disease in order to classify patients into subgroups for the purposes of predicting treatment response and suggesting outcome. By identifying those patients who are most likely to benefit from a given therapy, interventions can be tailored to avoid the expense and toxicity of futile treatment. Ultimately, the goal is to offer the right treatment, to the right patient, at the right time. Lung cancer is a heterogeneous disease both functionally and morphologically. Further, over time, clonal proliferations of cells may evolve, becoming resistant to specific therapies. PET is a sensitive imaging technique with an important role in the precision medicine algorithm of lung cancer patients. It provides anatomo-functional insight during diagnosis, staging, and restaging of the disease. It is a prognostic biomarker in lung cancer patients that characterizes tumoral heterogeneity, helps predict early response to therapy, and may direct the selection of appropriate treatment.

IASLC Multidisciplinary Recommendations for Pathologic Assessment of Lung Cancer Resection Specimens After Neoadjuvant Therapy

Currently, there is no established guidance on how to process and evaluate resected lung cancer specimens after neoadjuvant therapy in the setting of clinical trials and clinical practice. There is also a lack of precise definitions on the degree of pathologic response, including major pathologic response or complete pathologic response. For other cancers such as osteosarcoma and colorectal, breast, and esophageal carcinomas, there have been multiple studies investigating pathologic assessment of the effects of neoadjuvant therapy, including some detailed recommendations on how to handle these specimens. A comprehensive mapping approach to gross and histologic processing of osteosarcomas after induction therapy has been used for over 40 years. The purpose of this article is to outline detailed recommendations on how to process lung cancer resection specimens and to define pathologic response, including major pathologic response or complete pathologic response after neoadjuvant therapy. A standardized approach is recommended to assess the percentages of (1) viable tumor, (2) necrosis, and (3) stroma (including inflammation and fibrosis) with a total adding up to 100%. This is recommended for all systemic therapies, including chemotherapy, chemoradiation, molecular-targeted therapy, immunotherapy, or any future novel therapies yet to be discovered, whether administered alone or in combination. Specific issues may differ for certain therapies such as immunotherapy, but the grossing process should be similar, and the histologic evaluation should contain these basic elements. Standard pathologic response assessment should allow for comparisons between different therapies and correlations with disease-free survival and overall survival in ongoing and future trials. The International Association for the Study of Lung Cancer has an effort to collect such data from existing and future clinical trials. These recommendations are intended as guidance for clinical trials, although it is hoped they can be viewed as suggestion for good clinical practice outside of clinical trials, to improve consistency of pathologic assessment of treatment response.

Prognostic value of post-induction chemotherapy 18F-FDG PET-CT in stage II/III non-small cell lung cancer before (chemo-) radiation

INTRODUCTION

The purpose of our present study was to assess the prognostic impact of FDG PET-CT after induction chemotherapy for patients with inoperable non-small-cell lung cancer (NSCLC).

MATERIAL AND METHODS

This retrospective study included 50 patients with inoperable stage II/III NSCLC from January 2012 to July 2015. They were treated for curative intent with induction chemotherapy, followed by concomitant chemoradiation therapy or sequential radiation therapy. FDG PET-CT scans were acquired at initial staging (PET1) and after the last cycle of induction therapy (PET2). Five parameters were evaluated on both scans: SUVmax, SUVpeak, SUVmean, TLG, MTV, and their respective deltas. The prognostic value of each parameter for overall survival (OS) and progression-free survival (PFS) was evaluated with Cox proportional-hazards regression models.

RESULTS

Median follow-up was 19 months. PET1 parameters, clinical and histopathological data were not predictive of the outcome. TLG2 and ΔTLG were prognostic factors for OS. TLG2 was the only prognostic factor for PFS. For OS, log-rank test showed that there was a better prognosis for patients with TLG2< 69g (HR = 7.1, 95%CI 2.8-18, p = 0.002) and for patients with ΔTLG< -81% after induction therapy (HR = 3.8, 95%CI 1.5-9.6, p = 0.02). After 2 years, the survival rate was 89% for the patients with low TLG2 vs 52% for the others. We also evaluated a composite parameter considering both MTV2 and ΔSUVmax. Patients with MTV2> 23cc and ΔSUVmax> -55% had significantly shorter OS than the other patients (HR = 5.7, 95%CI 2.1-15.4, p< 0.01).

CONCLUSION

Post-induction FDG PET might be an added value to assess the patients' prognosis in inoperable stage II/III NSCLC. TLG, ΔTLG as well as the association of MTV and ΔSUVmax seemed to be valuable parameters, more accurate than clinical, pathological or pretherapeutic imaging data.

Predictive and Prognostic Role of Metabolic Response in Patients With Stage III NSCLC Treated With Neoadjuvant Chemotherapy

INTRODUCTION

The purpose of this study was to assess the predictive and prognostic role of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in candidates with stage III non-small-cell lung cancer (NSCLC) to neoadjuvant chemotherapy.

PATIENTS AND METHODS

Sixty-six patients with stage III NSCLC treated with induction chemotherapy from March 2013 to December 2017 were retrospectively identified. Response assessment were evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and European Organisation for Research and Treatment of Cancer (EORTC) criteria. 18F-FDG PET/CT metabolic parameters were analyzed as absolute values as well as percentage changes (Δ) between 2 consecutive scans, for primary tumor (T) and for regional lymph nodes (N). All clinical variables and metabolic parameters were compared with treatment response and correlated with progression-free survival (PFS) and overall survival (OS), based on a median follow-up of 9.4 months.

RESULTS

Post-induction therapy standardized uptake value (SUV)max_T, SUVmean_T, metabolic tumor volume (MTV_T), and total lesion glycolysis of the tumor (TLG_T) varied significantly between responders and non-responders (6.6 vs. 13.8; P = .001; 4.2 vs. 8.1; P < .001; 6 vs. 17.9; P = .002; and 24.1 vs. 136.3; P < .001, respectively). Likewise, percentage changes (Δ_T) were significantly different between the 2 groups (P < .001). Along with primary tumor, also post-SUVmax_N, post-SUVmean_N, and post-TLG_N (P = .024, P = .015, and P = .024, respectively), as well as all percentage changes (Δ_N) were different between responders and non-responders. RECIST 1.1 and EORTC response classifications were discordant in 27 patients (40.9%; κ = 0.265; P = .003). On multivariate analysis, post-TLG_N was an independent predictor for both PFS and OS, whereas RECIST 1.1 was a predictor only for OS.

CONCLUSIONS

Several metabolic parameters may differentiate responders from non-responders following neoadjuvant chemotherapy in stage III NSCLC. As compared with RECIST 1.1, EORTC seems to be more appropriate for evaluation therapeutic response. Finally, post-TLG_N has significant prognostic information.

Multidisciplinary consensus statement on the clinical management of patients with stage III non-small cell lung cancer

Stage III non-small cell lung cancer (NSCLC) is a very heterogeneous disease that encompasses patients with resected, potentially resectable and unresectable tumours. To improve the prognostic capacity of the TNM classification, it has been agreed to divide stage III into sub-stages IIIA, IIIB and IIIC that have very different 5-year survival rates (36, 26 and 13%, respectively). Currently, it is considered that both staging and optimal treatment of stage III NSCLC requires the joint work of a multidisciplinary team of expert physicians within the tumour committee. To improve the care of patients with stage III NSCLC, different scientific societies involved in the diagnosis and treatment of this disease have agreed to issue a series of recommendations that can contribute to homogenise the management of this disease, and ultimately to improve patient care.

Prognostic value of lymph node ratio after induction therapy in stage IIIA/N2 non-small cell lung cancer: a monocentric clinical study

Background

The optimal treatment modalities for patients with stage IIIA N2 non-small cell lung cancer (NSCLC) are still a matter of debate. To provide best outcome and to avoid unnecessary treatment patient selection for surgical therapy is crucial. In addition to mediastinal downstaging the lymph node ratio (LNR) has been suggested as a prognosticator in this patient group.

Methods

We retrospectively reviewed clinical and histopathologic data of 78 patients with stage IIIA N2 NSCLC, who underwent induction therapy with two cycles of platinum-based chemotherapy for intended surgery at our clinic between 2009 and 2016. To evaluate the prognostic value of the LNR the cut off was set at 0.33 as reported in prior literature.

Results

The median follow-up time was 30.1 months. In multivariate analysis mediastinal down staging was associated with a longer overall survival (OS): 52.2 (range, 5.9-89.7) months for ypN0 versus 24.6 (4.4-84.2) months for ypN1/2 (HR, 2.76; 95% CI, 1.07-7.1, P=0.0348). LNR ≤0.33 was linked to a better OS of 39.3 (range, 5.9-89.7) months compared to 14.7 (range, 4.4-66.2) months for a LNR >0.33 in univariate analysis (P=0.037). In multivariate analysis a statistical trend could be observed (HR, 2.82; 95% CI, 0.98-8.14, P=0.1). In patients with persistent lymph node involvement the LNR could also identify a subgroup of patients with a favorable prognosis (30.1 vs. 14.7 months, P=0.145).

Conclusions

Mediastinal downstaging remains the best prognosticator in stage IIIA N2 NSCLC after induction therapy. However, using the LNR in patients with persistent mediastinal lymph node metastasis a subgroup with a favorable prognosis could be identified. The LNR could aid in finding the best treatment modalities for these patients.

Prognostic Value of 18F-Fluorodeoxyglucose PET/Computed Tomography in Non-Small-Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related death with a poor prognosis. Numerous factors contribute to treatment outcome. 18F-fluorodeoxyglucose (FDG) uptake reflects tumor metabolic activity and is an important prognosticator in patients with NSCLC. Volume-based FDG-PET parameters reflect the metabolic status of a malignancy more accurately than maximum standardized uptake value and thus are better prognostic markers in lung cancer. FDG-avid tumor burden parameters may help clinicians to predict treatment outcomes before and during therapy so that treatment can be adjusted to achieve the best possible outcomes while avoiding side effects.

Maximum standardized uptake value on FDG-PET predicts survival in stage I non-small cell lung cancer following carbon ion radiotherapy

The present study (University Hospital Medical Information Network study no. UMIN000003797) aimed to evaluate whether the maximum standardized uptake value (SUV_max) of pretreatment ¹⁸F-fluorodeoxyglucose-positron emission tomography (FDG-PET) is prognostic factor for stage I non-small cell lung cancer (NSCLC) treated with carbon ion radiotherapy (C-ion RT). Patients treated between June 2010 and June 2013 at Gunma University Heavy Ion Medical Center (Maebashi, Japan) on a prospective protocol were included in the present study. Patients with T1a-b and T2a NSCLC were treated with C-ion RT at a dose of 52.8 Gy [relative biological effectiveness (RBE)] and 60.0 Gy (RBE), respectively, in four fractions. Prior to treatment, all patients underwent FDG-PET, in which the SUV_max of primary tumors was evaluated. Local control, progression-free survival (PFS), and overall survival (OS) were calculated. A total of 45 patients were analyzed and the median follow-up period was 28.9 months. The 2-year local control, PFS and OS rates for all patients were 93, 78 and 89%, respectively. The mean SUV_max of primary tumors was 5.5, and patients were divided into higher (≥5.5) and lower (<5.5) SUV_max groups. The 2-year PFS rates were 61 and 89% for the higher and lower SUV_max groups, respectively (P=0.01), and the 2-year OS rates for the higher and lower SUV_max groups were 76 and 96%, respectively (P=0.01). The higher SUV_max group exhibited a significantly worse PFS and OS compared with the lower SUV_max group; however, the SUV_max was not associated with the local control rate. In total, 2 patients (4%) experienced grade 2 or 3 radiation pneumonitis, with their symptoms improved through conservative treatment. No patients experienced any grade 4 or 5 toxicities. The results of the present study indicate that pretreatment SUV_max is a prognostic indicator for outcomes in patients with stage I NSCLC treated with C-ion RT.

The long-term prognosis of induction chemotherapy followed by surgery for N2 non-small cell lung cancer: A retrospective case series study

INTRODUCTION

The long-term prognosis of induction chemotherapy followed by surgery for N2 non-small lung cell cancer (NSCLC) remains controversial.

PATIENTS AND METHODS

We retrospectively reviewed the data and assessed the prognosis of 31 N2-NSCLC patients who underwent induction chemotherapy followed by surgery at our institution between January 1999 and December 2013. Potential prognostic factors, such as age, gender, tumor histology, tumor marker levels, tumor size, the number of N2 lymph nodes, the time from the last induction chemotherapy to the date of surgery, induction chemotherapy, RECIST response, downstaging status, pathological stage, adjuvant chemotherapy, and EF, were analyzed.

RESULTS

The chemotherapy regimens of 30 of the 31 patients included a platinum agent. Complete resection was performed in 96.7% of the cases. Pathological downstaging was induced in 9 (29%) of the 31 patients. The median follow-up period was 7.89 years. The median DFI was 13.9 months. The recurrence rate was 74.2%. The 5-year OS was 56.9%. Univariate analyses revealed that none of the factors significantly affected OS, while the tumor histology had a significant effect on the DFI.

CONCLUSION

Although the recurrence rate in our study was similar to previous studies, our survival data were much better than those of past reports. Although the tumor histology was the only factor that had a significant association with DFI in the current study, the possibility of bias exists.

Molecular Imaging and Precision Medicine in Lung Cancer

Precision medicine allows tailoring of preventive or therapeutic interventions to avoid the expense and toxicity of futile treatment given to those who will not respond. Lung cancer is a heterogeneous disease functionally and morphologically. PET is a sensitive molecular imaging technique with a major role in the precision medicine algorithm of patients with lung cancer. It contributes to the precision medicine of lung neoplasia by interrogating tumor heterogeneity throughout the body. It provides anatomofunctional insight during diagnosis, staging, and restaging of the disease. It is a biomarker of tumoral heterogeneity that helps direct selection of the most appropriate treatment, the prediction of early response to cytotoxic and cytostatic therapies, and is a prognostic biomarker in patients with lung cancer.

Mechanism and non-mechanism based imaging biomarkers for assessing biological response to treatment in non-small cell lung cancer

Therapeutic options in locally advanced non-small cell lung cancer (NSCLC) have expanded in the past decade to include a palate of targeted interventions such as high dose targeted thermal ablations, radiotherapy and growing platform of antibody and small molecule therapies and immunotherapies. Although these therapies have varied mechanisms of action, they often induce changes in tumour architecture and microenvironment such that response is not always accompanied by early reduction in tumour mass, and evaluation by criteria other than size is needed to report more effectively on response. Functional imaging techniques, which probe the tumour and its microenvironment through novel positron emission tomography and magnetic resonance imaging techniques, offer more detailed insights into and quantitation of tumour response than is available on anatomical imaging alone. Use of these biomarkers, or other rational combinations as readouts of pathological response in NSCLC have potential to provide more accurate predictors of treatment outcomes. In this article, the robustness of the more commonly available positron emission tomography and magnetic resonance imaging biomarker indices is examined and the evidence for their application in NSCLC is reviewed.

Microscopic N2 disease exhibits a better prognosis in resected non-small-cell lung cancer

OBJECTIVES

The management of pIIIA-N2 non-small-cell lung cancer (NSCLC) is still controversial. In particular, there are wide variations in overall survival (OS), suggesting the existence of subgroups among N2 patients. We aimed to evaluate the prognostic value of microscopic pN2 in NSCLC.

METHODS

Between 1996 and 2015, the data from all 982 pathologically stage IIIA-N2 patients who underwent surgery with curative intent for NSCLC were retrospectively reviewed. Microscopic pN2 disease was defined as a nodal metastasis ranging from 0.2 to 2 mm in size.

RESULTS

With a median follow-up of 17 months (2-101), the 5-year OS for the whole cohort was 31%. Microscopic N2 was observed in 309 (31.5%) patients. Microscopic N2 was associated with better median OS compared with macroscopic N2 [42 months (95% CI 36.85-47.15) vs 23 months (95% CI 19.7-26.29), P < 0.0001, with a corresponding 5-year OS rate of 39 and 21%, respectively]. In multivariate analysis, microscopic N2 remained a favourable independent prognostic factor [HR 0.681 (95% CI 0.481-0.967), P = 0.03]. The median OS of microscopic N2 patients who benefitted from simple follow-up was significantly better than those who underwent chemotherapy, radiation therapy or both [43 months (95% CI 24.22-61.78) vs 22 months (95% CI 17.43-26.47) vs 31 months (95% CI 27.66-34.34) vs 16 months (95% CI 14.6-17.4), P = 0.008].

CONCLUSION

Microscopic N2 seems to be associated with better prognosis in patients with pIIIA-N2 NSCLC and these could benefit from a simple follow-up. Prospective cohort studies are necessary to confirm these preliminary results.

Utility of Routine PET Imaging to Predict Response and Survival After Induction Therapy for Non-Small Cell Lung Cancer

BACKGROUND

Data from clinical trials suggest that changes in the glucose avidity of the primary site of lung cancer during induction therapy, measured by changes in (18)F-fluorodeoxyglucose positron emission tomography, correlate with tumor response. Little information about the utility of changes in positron emission tomography imaging of involved lymph nodes during induction chemotherapy is available. The utility of positron emission tomography imaging of either the primary site or nodal metastases, obtained during routine clinical care outside of a clinical trial setting, to predict response has also not been examined.

METHODS

A retrospective review of all surgical patients with non-small cell lung cancer at a single institution imaged between 2000 and 2006 with (18)F-fluorodeoxyglucose positron emission tomography before or after induction therapy was performed.

RESULTS

An increase in standardized uptake value in the primary site of disease during induction therapy was associated with reduced overall survival after resection. Neither pretreatment standardized uptake value nor percentage change in the primary site was associated with overall survival after resection. A decrease in standardized uptake value of greater than 60% in the involved N2 mediastinal nodes was the best predictor of overall survival, better than changes seen in the primary site of disease.

CONCLUSIONS

An increase in glucose avidity of non-small cell lung cancers during induction therapy was associated with a worse prognosis compared with stable or any decrease in standardized uptake value. Changes in the glucose avidity of mediastinal nodal metastases may be a stronger predictor of survival than changes in the primary site of disease.

Adaptive Neoadjuvant Chemotherapy Guided by (18)F-FDG PET in Resectable Non-Small Cell Lung Cancers: The NEOSCAN Trial

INTRODUCTION

Although perioperative chemotherapy improves survival in patients with resectable lung cancers, systemic recurrence remains common. Neoadjuvant chemotherapy permits response assessment and an opportunity to switch treatment regimens. Response measured by fludeoxyglucose ((18)F-FDG) positron emission tomography (PET) correlates with clinical outcomes better than computed tomography (CT) does. This trial assessed PET-measured response rate to alternative chemotherapy in patients with a suboptimal PET response after two cycles of neoadjuvant chemotherapy.

METHODS

This phase II study enrolled patients with resectable stage IB-IIIA lung cancers (primary tumor ≥ 2 cm and peak standard uptake value [SUVpeak] ≥ 4.5). Patients had a pretreatment (18)F-FDG PET/CT scan before two cycles of cisplatin (or carboplatin) plus gemcitabine (squamous cell carcinoma) or pemetrexed (adenocarcinoma) and then a repeat PET/CT scan. If SUVpeak in the primary tumor decreased by at least 35%, patients continued the initial chemotherapy. Individuals with less than a 35% PET response were switched to vinorelbine plus docetaxel. Postoperative radiotherapy was recommended to all patients with positive N2 nodes. A Simon's optimal two-stage design was used to evaluate the primary end point of a PET Response in Solid Tumors-defined response rate to vinorelbine plus docetaxel in previously nonresponding patients.

RESULTS

Forty patients were enrolled. Fifteen patients (38% [95% confidence interval: 38-53]) had less than a 35% decrease in SUVpeak, and 13 received vinorelbine plus docetaxel. The study met its primary end point with 10 of 15 PET metabolic responses to alternate therapy (67%). Chemotherapy toxicities never precluded surgical exploration.

CONCLUSIONS

Utilizing (18)F-FDG PET/CT to assess response and change preoperative chemotherapy in nonresponding patients can improve radiographic measures of response. This adaptive approach can also be used to test new drugs, attempting to optimize perioperative chemotherapy to achieve better long-term outcomes.

Volumetric comparison of positron emission tomography/computed tomography using 4'-[methyl-¹¹C]-thiothymidine with 2-deoxy-2-¹⁸F-fluoro-D-glucose in patients with advanced head and neck squamous cell carcinoma

OBJECTIVE

We prospectively compared the diagnostic value of PET/computed tomography (CT) findings using the tracers 4'-[methyl-11C]-thiothymidine (11C-4DST) and 2-deoxy-2-18F-fluoro-D-glucose (18F-FDG) in patients with head and neck squamous cell carcinoma (HNSCC).

PATIENTS AND METHODS

Thirty-eight patients with advanced HNSCC underwent 11C-4DST PET/CT and 18F-FDG PET/CT before treatment. Maximum standardized uptake values (SUVmax) were measured for both PET/CT studies; in addition, total lesion glycolysis (TLG) of 18F-FDG PET/CT and total lesion proliferation (TLP) of 11C-4DST PET/CT were measured. Absolute TLG and TLP values as well as values with various SUV thresholds were measured. All patients were followed up for 13.5±7.5 months (mean±SD) to monitor recurrence.

RESULTS

A statistically significant correlation was observed between the primary tumor SUVmax for 11C-4DST PET/CT and 18F-FDG PET/CT (r=0.46, P<0.01). TLP values with SUV thresholds strongly correlated with TLG values relative to the same thresholds (r=0.60-0.92, P<0.001). Nine of the 38 patients with post-treatment recurrence were identified. Receiver operating characteristic curves for TLG3.0 and TLP2.5 showed the highest prognostic ability for recurrence; the sensitivity and specificity of TLG3.0 were 89 and 72%, respectively, and the sensitivity and specificity of TLP2.5 were 89 and 55%, respectively.

CONCLUSION

In patients with advanced HNSCC, the TLP of 11C-4DST PET/CT strongly correlated with the TLG of 18F-FDG PET/CT. Although there were no large differences between these values, the receiver operating characteristic curves of the absolute TLG had slightly better prognostic ability for recurrence.

Role of adjuvant radiotherapy in completely resected non-small-cell lung cancer

Most long-term survivors of non-small-cell lung cancer (NSCLC) are patients who have had a completely resected tumour. However, this is only achievable in about 30% of the patients. Even in this highly selected group of patients, there is still a high risk of both local and distant failure. Adjuvant treatments such as chemotherapy (CT) and radiotherapy (RT) have therefore been evaluated in order to improve their outcome. In patients with stage II and III, administration of adjuvant platinum-based chemotherapy is now considered the standard of care, based on level 1 evidence. The role of postoperative radiation therapy (PORT) remains controversial. In the PORT meta-analysis published in 1998, the conclusions were that if PORT was detrimental to patients with stage I and II completely resected NSCLC, the role of PORT in the treatment of tumours with N2 involvement was unclear and further research was warranted. Thus at present, after complete resection, adjuvant radiotherapy should not be administered in patients with early lung cancer. Recent retrospective and non-randomised studies, as well as subgroup analyses of recent randomised trials evaluating adjuvant chemotherapy, provide evidence of the possible benefit of PORT in patients with mediastinal nodal involvement. The role of PORT needs to be evaluated also for patients with proven N2 disease who undergo neoadjuvant chemotherapy followed by surgery. The risk of local recurrence for N2 patients varies between 20% and 60%. Based on currently available data, PORT should be discussed for fit patients with completely resected NSCLC with N2 nodal involvement, preferably after completion of adjuvant chemotherapy or after surgery if patients have had preoperative chemotherapy. There is a need for new randomised evidence to reassess PORT using modern three-dimensional conformal radiation technique, with attention to normal organ sparing, particularly lung and heart, to reduce the possible over-added toxicity. Quality assurance of radiotherapy as well as quality of surgery – and most particularly nodal exploration modality – should both be monitored. A new large multi-institutional randomised trial Lung ART evaluating PORT in this patient population is needed and is now under way.

Lung cancer

(18)F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) plays a key role in the evaluation of undiagnosed lung nodules, when primary lung cancer is strongly suspected, or when it has already been diagnosed by other techniques. Although technical factors may compromise characterization of small or highly mobile lesions, lesions without apparent FDG uptake can generally be safely observed, whereas FDG-avid lung nodules almost always need further evaluation. FDG-PET/CT is now the primary staging imaging modality for patients with lung cancer who are being considered for curative therapy with either surgery or definitive radiation therapy.

(18)F-fluorodeoxyglucose positron emission tomography to assess response after radiation therapy in anaplastic thyroid cancer

AIM

To assess the interest of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET/CT) to evaluate the tumor response after radiotherapy (RT) in anaplastic thyroid cancer (ATC) patients.

METHODS AND MATERIALS

92 patients were treated for ATC at our institution from 1987 to 2012, out of which 64 (70%) received an aggressive multimodal treatment and 28 (30%) a palliative treatment. In the multimodal treatment group, curative-intended surgery, chemotherapy, and RT were delivered in 35 (55%), 59 (92%), and 56 (88%) patients. The maximum standardized uptake value (SUVmax) was determined in tumor (T), nodes (N) and metastases (M) in each available (18)F-FDG PET/CT.

RESULTS

The median follow-up was 3.2years. The 1-year actuarial overall survival (OS) was 18% (median: 5.2months) in the entire population and 27% (median: 7months) in the multimodal treatment group. In the multivariate analysis, RT, surgery, and pre-RT chemotherapy independently predicted for OS, with HRs respectively of 0.1, 0.3, and 0.5. Quantification of FDG uptake with SUVmax was assessable in 26 (40%), 19 (30%), and 25 (39%) of (18)F-FDG PET/CT performed initially (prior to any treatment), prior to RT, and after RT, respectively. Mean SUVmax significantly decreased in T (p<0.001), but not in N (p=0.1) and M (p=0.3) during the assessment period, which might be related to the local effect of RT. Comparing pre- and post-RT (18)F-FDG PET/CT, the T mean relative SUVmax decrease was lower (23±54%) in the 4 patients that had a local relapse (LR) as compared with others in the 12 others patients (62±33%; p=0.3). A relative SUVmax decrease inferior to 20% significantly predicted for LR (p=0.02).

CONCLUSION

The prognosis of ATC patients remains dismal despite an aggressive multimodal treatment. Although our results were not significant, (18)F-FDG PET/CT could potentially serve as a surrogate marker of treatment response in ATC.

Positron Emission Tomography (PET) in Oncology

Since its introduction in the early nineties as a promising functional imaging technique in the management of neoplastic disorders, FDG-PET, and subsequently FDG-PET/CT, has become a cornerstone in several oncologic procedures such as tumor staging and restaging, treatment efficacy assessment during or after treatment end and radiotherapy planning. Moreover, the continuous technological progress of image generation and the introduction of sophisticated software to use PET scan as a biomarker paved the way to calculate new prognostic markers such as the metabolic tumor volume (MTV) and the total amount of tumor glycolysis (TLG). FDG-PET/CT proved more sensitive than contrast-enhanced CT scan in staging of several type of lymphoma or in detecting widespread tumor dissemination in several solid cancers, such as breast, lung, colon, ovary and head and neck carcinoma. As a consequence the stage of patients was upgraded, with a change of treatment in 10%-15% of them. One of the most evident advantages of FDG-PET was its ability to detect, very early during treatment, significant changes in glucose metabolism or even complete shutoff of the neoplastic cell metabolism as a surrogate of tumor chemosensitivity assessment. This could enable clinicians to detect much earlier the effectiveness of a given antineoplastic treatment, as compared to the traditional radiological detection of tumor shrinkage, which usually takes time and occurs much later.

Multimodality treatment with surgery for locally advanced non-small-cell lung cancer with n2 disease: a review article

Stage III non-small-cell lung cancer (NSCLC) is composed of a heterogeneous population of lesions (ie, T4N0-3, T3N1-3, and T1a-2aN2-3), which makes it difficult to establish a definitive treatment strategy. Although several retrospective and prospective studies have been conducted to investigate the significance of multimodality treatments with surgery for patients with resectable stage III NSCLC, the role of surgery still remains controversial. In this article, we review the results of retrospective and prospective studies that have investigated the significance of multimodality treatment with surgery for patients with stage III NSCLC, particularly those with mediastinal lymph node metastasis, and the implications for the treatment of this controversial subset of patients.

PET/CT in therapy evaluation of patients with lung cancer

FDG-PET/CT is a well documented and widespread used imaging modality for the diagnosis and staging of patient with lung cancer. FDG-PET/CT is increasingly used for the assessment of treatment effects during and after chemotherapy. However, PET is not an accepted surrogate end-point for assessment of response rate in clinical trials. The aim of this review is to present current evidence on the use of PET in response evaluation of patients with lung cancer and to introduce the pearls and pitfalls of the PET-technology relating to response assessment. Based on this and relating to validation criteria, including stable technology, standardization, reproducibility and broad availability, the review discusses why, despite numerous studies on response assessment indicating a possible role for FDG-PET/CT, PET still has no place in guidelines relating to response evaluation in lung cancer.

Phase II trial of neoadjuvant bevacizumab plus chemotherapy and adjuvant bevacizumab in patients with resectable nonsquamous non-small-cell lung cancers

INTRODUCTION

Bevacizumab improves survival in patients with advanced non-small-cell lung cancer (NSCLC). This phase II clinical trial assessed the effects of the addition of bevacizumab to neoadjuvant chemotherapy in resectable nonsquamous NSCLC.

METHODS

Patients with resectable stage IB-IIIA nonsquamous NSCLC were treated with bevacizumab followed by imaging 2 weeks later to assess single-agent effect. After this they received two cycles of bevacizumab with four cycles of cisplatin and docetaxel followed by surgical resection. Resected patients were eligible for adjuvant bevacizumab. The primary endpoint was the rate of pathological downstaging (decrease from pretreatment clinical stage to post-treatment pathological stage). Secondary endpoints included overall survival, safety, and radiologic response.

RESULTS

Fifty patients were enrolled. Thirty-four (68%) were clinical stage IIIA. All three doses of neoadjuvant bevacizumab were delivered to 40 of 50 patients. Six patients (12%) discontinued because of bevacizumab-related adverse events. The rate of downstaging (38%), response to chemotherapy (45%), and perioperative complications (12%) were comparable with historical data. No partial responses were observed to single-agent bevacizumab, but 18% of the patients developed new intratumoral cavitation, with a trend toward improved pathologic response (57% versus 21%; p = 0.07). A major pathologic response (≥90% treatment effect) was associated with survival at 3 years (100% versus 49%; p = 0.01). No patients with KRAS-mutant NSCLC (0 of 10) had a pathologic response as compared with 11 of 31 with wild-type KRAS.

CONCLUSION

Although preoperative bevacizumab plus chemotherapy was feasible, it did not improve downstaging in unselected patients. New cavitation after single-agent bevacizumab is a potential biomarker. Alternative strategies are needed for KRAS-mutant tumors.

(18)F-FDG-PET/CT in assessing response to neoadjuvant chemoradiotherapy for potentially resectable locally advanced esophageal cancer

PURPOSE

To correlate metabolic response to neoadjuvant chemoradiotherapy (NACR) on FDG-PET/CT using PERCIST-based criteria to pathologic and clinical response, and survival in patients with locally advanced esophageal cancer (LAEC).

MATERIALS AND METHODS

Forty-five patients with LAEC underwent PET/CT at baseline and after NACR. Tumors were evaluated using PERCIST (PET response criteria in solid tumors)-based criteria including SUL, SUL tumor/liver ratio, % change in SUL. These parameters were compared to pathology regression grade (PRG), clinical response (including residual or new disease beyond the surgical specimen), and overall survival.

RESULTS

On surgical pathology, there was complete or near-complete regression of tumor in 51.1 %, partial response in 42.2 %, and lack regression in 4.4 %. One patient (2.2 %) had progression of disease on imaging and did not undergo surgical resection. None of the baseline PET parameters had significant correlation to pathology regression grade or clinical response. On follow-up, a positive correlation was found between post-therapy SUL ratio, %∆ SUL and %∆ SUL ratio and clinical response (p = 0.025, 0.035, 0.030, respectively). A weak correlation was found between post-therapy SUL ratio to PRG (p = 0.049). A strong correlation was found between the metabolic response score and PRG (p = 0.002) as well as between metabolic response and clinical response (p < 0.001).

CONCLUSION

PERCIST-based metabolic response assessment to NACR in LAEC may correlate with clinical outcome and survival.

Recent Trends in PET Image Interpretations Using Volumetric and Texture-based Quantification Methods in Nuclear Oncology

Image quantification studies in positron emission tomography/computed tomography (PET/CT) are of immense importance in the diagnosis and follow-up of variety of cancers. In this review we have described the current image quantification methodologies employed in (18)F-fluorodeoxyglucose ((18)F-FDG) PET in major oncological conditions with particular emphasis on tumor heterogeneity studies. We have described various quantitative parameters being used in PET image analysis. The main contemporary methodology is to measure tumor metabolic activity; however, analysis of other image-related parameters is also increasing. Primarily, we have identified the existing role of tumor heterogeneity studies in major cancers using (18)F-FDG PET. We have also described some newer radiopharmaceuticals other than (18)F-FDG being studied/used in the management of these cancers. Tumor heterogeneity studies are being performed in almost all major oncological conditions using (18)F-FDG PET. The role of these studies is very promising in the management of these conditions.

Radiographic evaluation of the patient with lung cancer: surgical implications of imaging

Lung cancer is the leading cause of cancer deaths in the United States. Despite many advances in treatment, surgery remains the preferred treatment modality for patients presenting with early stage disease. Imaging is critical in the preoperative evaluation of these patients being considered for a curative resection. Advanced imaging techniques provide valuable information, including primary diagnostics, staging, and intraoperative localization for suspected lung cancer. Knowledge of surgical implications of imaging findings can aid both radiologists and surgeons in delivering safe and effective care.

Retrospective study of surgical resection in the treatment of limited stage small cell lung cancer

BACKGROUND

Patients with small cell lung cancer (SCLC) are mainly treated by chemotherapy/radiotherapy, either alone or combined. Surgical resection is an optional treatment for few SCLC patients. The efficacy of surgical intervention for SCLC remains controversial. This study evaluates the validity of surgery for patients with limited stage SCLC.

METHODS

We conducted a retrospective review of 59 patients with limited stage SCLC who received trimodal therapy from 2004 to 2011. Progression-free survival (PFS) and overall survival (OS) were calculated using the statistic methods of Kaplan-Meier and the log-rank test.

RESULTS

Among the 59 limited stage SCLC patients, 54 patients with stage I-III SCLC received surgical treatment with curative intent, and 42.6% (23/54) patients received preoperative chemotherapy. The radical resection rate of the group of preoperative chemotherapy and the group of initial surgical resection were 82.6% (19/23) and 54.8% (17/31), respectively. The corresponding five-year survival rates were 59% and 22% with significant differences (P = 0.032 and 0.041, respectively). In total, 36 (66.7%) patients underwent radical surgery with resection of the primary mass and mediastinal lymph nodes. In the radical surgery series, five-year survival, according to stage I-III categories, were 59%, 53%, and 26%, respectively. For the 30 stage III patients, the five-year survival of the radical group of 26% was lower than the non-radical group of 67%, and PFS analysis showed similar tendencies.

CONCLUSION

Preoperative chemotherapy is the most favorable initial treatment for patients with limited disease SCLC. Complete surgical resection is considered for patients with stage I and II. Surgical resection remains of no benefit for stage III SCLC patients with persistent N2/N3 after chemotherapy.

Modern post-operative radiotherapy for stage III non-small cell lung cancer may improve local control and survival: a meta-analysis

BACKGROUND

We hypothesized that modern postoperative radiotherapy (PORT) could decrease local recurrence (LR) and improve overall survival (OS) in patients with stage IIIA-N2 non-small-cell lung cancer (NSCLC).

METHODS

To investigate the effect of modern PORT on LR and OS, we identified published phase III trials for PORT and stratified them according to use or non-use of linear accelerators. Non-individual patient data were used to model the potential benefit of modern PORT in stage IIIA-N2 NSCLC treated with induction chemotherapy and resection.

RESULTS

Of the PORT phase III studies, eleven trials (2387 patients) were included for OS analysis and eight (1677 patients) for LR. PORT decreased LR, whether given with cobalt, cobalt and linear accelerators, or with linear accelerators only. An increase in OS was only seen when PORT was given with linear accelerators, along with the most significant effect on LR (relative risk for LR and OS 0.31 (p=0.01) and 0.76 (p=0.02) for PORT vs. controls, respectively). Four trials (357 patients) were suitable to assess LR rates in stage III NSCLC treated with surgery, in most cases after induction chemotherapy. LR as first relapse was 30% (105/357) after 5 years. In the modeling part, PORT with linear accelerators was estimated to reduce LR rates to 10% as first relapse and to increase the absolute 5-year OS by 13%.

CONCLUSIONS

This modeling study generates the hypothesis that modern PORT may increase both LR and OS in stage IIIA-N2 NSCLC even in patients being treated with induction chemotherapy and surgery.

Treatment of stage III non-small cell lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines

OBJECTIVES

Stage III non-small cell lung cancer (NSCLC) describes a heterogeneous population with disease presentation ranging from apparently resectable tumors with occult microscopic nodal metastases to unresectable, bulky nodal disease. This review updates the published clinical trials since the last American College of Chest Physicians guidelines to make treatment recommendations for this controversial subset of patients.

METHODS

Systematic searches were conducted through MEDLINE, Embase, and the Cochrane Database for Systematic Review up to December 2011, focusing primarily on randomized trials, selected meta-analyses, practice guidelines, and reviews.

RESULTS

For individuals with stage IIIA or IIIB disease, good performance scores, and minimal weight loss, treatment with combined chemoradiotherapy results in better survival than radiotherapy alone. Consolidation chemotherapy or targeted therapy following definitive chemoradiation for stage IIIA is not supported. Neoadjuvant therapy followed by surgery is neither clearly better nor clearly worse than definitive chemoradiation. Most of the arguments made regarding patient selection for neoadjuvant therapy and surgical resection provide evidence for better prognosis but not for a beneficial impact of this treatment strategy; however, weak comparative data suggest a possible role if only lobectomy is needed in a center with a low perioperative mortality rate. The evidence supports routine platinum-based adjuvant chemotherapy following complete resection of stage IIIA lung cancer encountered unexpectedly at surgery. Postoperative radiotherapy improves local control without improving survival.

CONCLUSIONS

Multimodality therapy is preferable in most subsets of patients with stage III lung cancer. Variability in the patients included in randomized trials limits the ability to combine results across studies and thus limits the strength of recommendations in many scenarios. Future trials are needed to investigate the roles of individualized chemotherapy, surgery in particular cohorts or settings, prophylactic cranial radiation, and adaptive radiation.

Positron emission tomography-computed tomography in the management of lung cancer: An update

This communication presents an update on the current role of positron emission tomography-computed tomography (PET-CT) in the various clinical decision-making steps in lung carcinoma. The modality has been reported to be useful in characterizing solitary pulmonary nodules, improving lung cancer staging, especially for the detection of nodal and metastatic site involvement, guiding therapy, monitoring treatment response, and predicting outcome in non-small cell lung carcinoma (NSCLC). Its role has been more extensively evaluated in NSCLC than small cell lung carcinoma (SCLC). Limitations in FDG PET-CT are encountered in cases of tumor histotypes characterized by low glucose uptake (mucinous forms, bronchioalveolar carcinoma, neuroendocrine tumors), in the assessment of brain metastases (high physiologic 18F-FDG uptake in the brain) and in cases presenting with associated inflammation. The future potentials of newer PET tracers beyond FDG are enumerated. An evolving area is PET-guided assessment of targeted therapy (e.g., EGFR and EGFR tyrosine kinase overexpression) in tumors which have significant potential for drug development.

Performance of integrated positron emission tomography/computed tomography for mediastinal nodal staging in non-small cell lung carcinoma

Integrated positron emission tomography (PET)/CT is routinely used for mediastinal nodal staging of non-small cell lung carcinoma in centers throughout the world. This modality is the most accurate noninvasive means by which to identify metastatic disease in mediastinal lymph nodes. This article reviews the evidence supporting the use of PET/CT and discusses the clinical applicability of this modality.

Prognostic implications of volume-based measurements on FDG PET/CT in stage III non-small-cell lung cancer after induction chemotherapy

PURPOSE

We sought to determine whether metabolic volume-based measurements on FDG PET/CT scans could provide additional information for predicting outcome in patients with stage III non-small-cell lung cancer (NSCLC) treated with induction chemotherapy.

METHODS

Included in the study were 32 patients with stage III NSCLC who were treated with induction platinum-based chemotherapy followed in 21 by surgery. All patients had an FDG PET/CT scan before and after the induction chemotherapy. Tumours were delineated using adaptive threshold methods. The SUVmax, SUVpeak, SUVmean, tumour volume (TV), total lesion glycolysis (TLG), and volume and largest diameter on the CT images (CTV and CTD, respectively) were calculated. Index ratios of the primary tumour were calculated by dividing the follow-up measurements by the baseline measurements. The prognostic value of each parameter for event-free survival (EFS) was determined using Cox regression models.

RESULTS

The median follow-up time was 19 months (range 6-43 months). Baseline PET and CT parameters were not significant prognostic factors. After induction therapy, only SUVmax, SUVpeak, SUVmean, TV, TLG and CTV were prognostic factors for EFS, in contrast to CTD. Of the index ratios, only TV and TLG ratios were prognostic factors for EFS. Patients with a TLG ratio <0.48 had a longer EFS than those with a TLG ratio >0.48 (13.9 vs. 9.2 months, p = 0.04). After adjustment for the effect of surgical treatment, all the parameters significantly correlated with EFS remained significant.

CONCLUSION

SUV, metabolic volume-based indices, and CTV after induction chemotherapy give independent prognostic information in stage III NSCLC. However, changes in metabolic TV and TLG under induction treatment provide more accurate prognostic information than SUV alone, and CTD and CTV.

Are pretreatment 18F-FDG PET tumor textural features in non-small cell lung cancer associated with response and survival after chemoradiotherapy?

There is evidence in some solid tumors that textural features of tumoral uptake in (18)F-FDG PET images are associated with response to chemoradiotherapy and survival. We have investigated whether a similar relationship exists in non-small cell lung cancer (NSCLC).

METHODS

Fifty-three patients (mean age, 65.8 y; 31 men, 22 women) with NSCLC treated with chemoradiotherapy underwent pretreatment (18)F-FDG PET/CT scans. Response was assessed by CT Response Evaluation Criteria in Solid Tumors (RECIST) at 12 wk. Overall survival (OS), progression-free survival (PFS), and local PFS (LPFS) were recorded. Primary tumor texture was measured by the parameters coarseness, contrast, busyness, and complexity. The following parameters were also derived from the PET data: primary tumor standardized uptake values (SUVs) (mean SUV, maximum SUV, and peak SUV), metabolic tumor volume, and total lesion glycolysis.

RESULTS

Compared with nonresponders, RECIST responders showed lower coarseness (mean, 0.012 vs. 0.027; P = 0.004) and higher contrast (mean, 0.11 vs. 0.044; P = 0.002) and busyness (mean, 0.76 vs. 0.37; P = 0.027). Neither complexity nor any of the SUV parameters predicted RECIST response. By Kaplan-Meier analysis, OS, PFS, and LPFS were lower in patients with high primary tumor coarseness (median, 21.1 mo vs. not reached, P = 0.003; 12.6 vs. 25.8 mo, P = 0.002; and 12.9 vs. 20.5 mo, P = 0.016, respectively). Tumor coarseness was an independent predictor of OS on multivariable analysis. Contrast and busyness did not show significant associations with OS (P = 0.075 and 0.059, respectively), but PFS and LPFS were longer in patients with high levels of each (for contrast: median of 20.5 vs. 12.6 mo, P = 0.015, and median not reached vs. 24 mo, P = 0.02; and for busyness: median of 20.5 vs. 12.6 mo, P = 0.01, and median not reached vs. 24 mo, P = 0.006). Neither complexity nor any of the SUV parameters showed significant associations with the survival parameters.

CONCLUSION

In NSCLC, baseline (18)F-FDG PET scan uptake showing abnormal texture as measured by coarseness, contrast, and busyness is associated with nonresponse to chemoradiotherapy by RECIST and with poorer prognosis. Measurement of tumor metabolic heterogeneity with these parameters may provide indices that can be used to stratify patients in clinical trials for lung cancer chemoradiotherapy.