A prospective study of PET/CT in initial staging of small-cell lung cancer: comparison with CT, bone scintigraphy and bone marrow analysis

Prognostic value of volumetric metabolic parameters measured by [18F]fluorodeoxyglucose-positron emission tomography/computed tomography in patients with small cell lung cancer

Background

We evaluated the prognostic value of volume-based metabolic positron emission tomography (PET) parameters in patients with small cell lung cancer (SCLC) compared with other factors.

Methods

The subjects were 202 patients with pathologically proven SCLC who underwent pretreatment ¹⁸F-fluorodeoxyglucose (FDG) PET/computed tomography (CT). Volumetric metabolic parameters of intrathoracic malignant hypermetabolic lesions, including maximum and average standardized uptake value, sum of metabolic tumor volume (MTV), and sum of total lesion glycolysis (TLG) were measured.

Results

164 patients had died during follow-up (median 17.4 months) and median overall survival was 14 months. On univariate survival analysis, age, stage, treatment modality, sum of MTV (cutoff = 100 cm³), and sum of TLG (cutoff = 555) were significant predictors of survival. There was a very high correlation between the sum of MTV and the sum of TLG (r = 0.963, P < 0.001). On multivariate survival analysis, age (HR = 1.04, P < 0.001), stage (HR = 2.442, P < 0.001), and sum of MTV (HR = 1.662, P = 0.002) were independent prognostic factors. On subgroup analysis based on limited disease (LD) and extensive disease (ED), sum of MTV and sum of TLG were significant prognostic factors only in LD.

Conclusion

Both sum of MTV and sum of TLG of intrathoracic malignant hypermetabolic lesions are important independent prognostic factors for survival in patients with SCLC, in addition to age and clinical stage. However, it may be more useful in limited disease rather than in extensive disease.

Progress in the management of limited-stage small cell lung cancer

Approximately 15% of lung cancer cases are of the small cell subtype, but this variant is highly aggressive and is often diagnosed at advanced stages. Outcomes after current treatment regimens have been poor, with 5-year survival rates as low as 25% for patients with limited-stage disease. Advances in therapy for small cell lung cancer have included the development of more effective chemotherapeutic agents and radiation techniques. For example, hyperfractionated radiotherapy given early in the course of the disease can reduce local recurrence and extend survival. Other technologic advances in radiation planning and delivery such as intensity-modulated radiotherapy, image-guided adaptive radiotherapy, and 4-dimensional computed tomography/positron emission tomography have facilitated the design of treatment volumes that closely conform to the shape of the tumor, which allows higher radiation doses to be given while minimizing radiation-induced toxicity to adjacent structures. Future improvements in outcomes will require clarifying the molecular basis for this disease.

Functional imaging in lung cancer

Lung cancer represents an increasingly frequent cancer diagnosis worldwide. An increasing awareness on smoking cessation as an important mean to reduce lung cancer incidence and mortality, an increasing number of therapy options and a steady focus on early diagnosis and adequate staging have resulted in a modestly improved survival. For early diagnosis and precise staging, imaging, especially positron emission tomography combined with CT (PET/CT), plays an important role. Other functional imaging modalities such as dynamic contrast-enhanced CT (DCE-CT) and diffusion-weighted MR imaging (DW-MRI) have demonstrated promising results within this field. The purpose of this review is to provide the reader with a brief and balanced introduction to these three functional imaging modalities and their current or potential application in the care of patients with lung cancer.

Small cell carcinoma of the liver and biliary tract without jaundice

An 80-year-old woman presenting with chest pain was found to have a large, lobulated soft tissue mass in the liver and nearby tissues on abdominal computed tomography (CT). The tumor had invaded the common hepatic artery and main portal vein. Jaundice developed 4 wk later, at which point, a pancreas and biliary CT scan revealed a large mass in the right lobe of the liver and a hilar duct obstruction, which was found to be a small cell carcinoma. Despite its rarity, liver and bile duct small cell carcinoma should be considered in the differential diagnosis of atypical chest pain without jaundice.

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

BACKGROUND

Small cell lung cancer (SCLC) is a lethal disease for which there have been only small advances in diagnosis and treatment in the past decade. Our goal was to revise the evidence-based guidelines on staging and best available treatment options.

METHODS

A comprehensive literature search covering 2004 to 2011 was conducted in MEDLINE, Embase, and five Cochrane databases using SCLC terms. This was cross-checked with the authors' own literature searches and knowledge of the literature. Results were limited to research in humans and articles written in English.

RESULTS

The staging classification should include both the old Veterans Administration staging classification of limited stage (LS) and extensive stage (ES), as well as the new seventh edition American Joint Committee on Cancer/International Union Against Cancer staging by TNM. The use of PET scanning is likely to improve the accuracy of staging. Surgery is indicated for carefully selected stage I SCLC. LS disease should be treated with concurrent chemoradiotherapy in patients with good performance status. Thoracic radiotherapy should be administered early in the course of treatment, preferably beginning with cycle 1 or 2 of chemotherapy. Chemotherapy should consist of four cycles of a platinum agent and etoposide. ES disease should be treated primarily with chemotherapy consisting of a platinum agent plus etoposide or irinotecan. Prophylactic cranial irradiation prolongs survival in those individuals with both LS and ES disease who achieve a complete or partial response to initial therapy. To date, no molecularly targeted therapy agent has demonstrated proven efficacy against SCLC.

CONCLUSION

Evidence-based guidelines are provided for the staging and treatment of SCLC. LS-SCLC is treated with curative intent with 20% to 25% 5-year survival. ES-SCLC is initially responsive to standard treatment, but almost always relapses, with virtually no patients surviving for 5 years. Targeted therapies have no proven efficacy against SCLC.

Small cell lung cancer

Neuroendocrine tumors account for approximately 20% of lung cancers; most (≈15%) are small cell lung cancer (SCLC). These NCCN Clinical Practice Guidelines in Oncology for SCLC focus on extensive-stage SCLC because it occurs more frequently than limited-stage disease. SCLC is highly sensitive to initial therapy; however, most patients eventually die of recurrent disease. In patients with extensive-stage disease, chemotherapy alone can palliate symptoms and prolong survival in most patients; however, long-term survival is rare. Most cases of SCLC are attributable to cigarette smoking; therefore, smoking cessation should be strongly promoted.

Imaging features of extrapulmonary small cell carcinoma

Small cell carcinoma accounts for approximately 20% of lung cancers; however, it rarely occurs at other sites. Extrapulmonary small cell carcinoma (EPSCC) is notoriously aggressive with a strong propensity for both regional and distant spread. The majority of the literature on these uncommon tumours is from a clinicopathological viewpoint with a relative paucity of detail regarding the radiological findings. This review will focus on the imaging features of EPSCC in its predominant sites of origin: the gastrointestinal tract, genitourinary tract, head, neck, and breast. We will also discuss the role of positron-emission tomography (PET)/computed tomography (CT) in the staging of EPSCC.

Clinical applicability of staging small cell lung cancer according to the seventh edition of the TNM staging system

The two-stage system of limited and extensive disease has been widely employed for small cell lung cancer (SCLC). However, the International Association for the Study of Lung Cancer has proposed that the TNM classification should be incorporated into clinical practice. The purpose of this study was to evaluate the applicability of the Union for International Cancer Control (UICC) 7th TNM staging system to SCLC. We retrospectively reviewed the medical records of consecutive patients with newly diagnosed histologically proven SCLC between March 2005 and January 2010. Patients who had other concurrent malignancies or had combined-type SCLC were excluded. We assessed overall survival (OS) according to the T descriptor, N descriptor, M descriptor, and TNM stage grouping. In total, 320 SCLC patients were included. Median age was 65 years and 286 patients (89.4%) were male. Median OS was 12.7 months. There were no significant differences in OS according to the T descriptor (P = 0.880). However, there were significant differences in OS according to the N (P < 0.001) and M (P < 0.001) descriptors and TNM stage grouping (P < 0.001). Hazard ratios for OS, adjusted for known prognostic factors, differed significantly according to the N and M descriptor, and TNM stage grouping, but not according to the T descriptors. The UICC 7th TNM staging system may contribute to a more precise prognosis in SCLC patients. Further studies are required to evaluate the applicability of the TNM staging system to SCLC.

Increasing Role of FDG-PET/CT in Detecting Bone Marrow Metastasis of Solid Tumors in Adults: An Analysis of Ten Patients

Background

We aimed to test the hypothesis that whether FDG-PET/CT which was ordered for various purposes can predict suspected or particularly unsuspected bone marrow metastasis (BMM) from the complete blood count and therefore can change the management of these patients.

Methods

In this retrospective study, the study sample consisted of 68 subsequent patients presented to our institution’s pathology department with bone marrow metastases of solid tumors. PET/CT was found to have been ordered in 10 out of 68 patients (6.8%) for various purposes. All patients gave informed consent about the PET/CT examinations and bone marrow biopsies.

Result

FDG-PET/CT was ordered in 10 out of 68 solid tumor patients with pathologically proven BMM. Of these 10 patients, 3 were female and 7 were male; mean age was 54.7 years. While FDG PET/CT showed bone and BMM in 4 of 10 patients (40%), the rest of the patients had BMM without bone involvement. Five patients (50%) who had probable bone marrow involvement on their FDG PET/CT scans had unsuspected complete blood counts with regard to BMM.

Conclusion

PET/CT has the ability to detect a substantial number of metabolically active tumor cells in the bone marrow in all of our patients which we proved by bone marrow biopsies. We think that this cohort of patients with solid tumors is hypothesis-generating with regard to detecting early bone marrow metastases by FDG PET/CT.

Detection of rib metastases in patients with lung cancer: a comparative study of MRI, CT and bone scintigraphy

We retrospectively investigated the imaging findings of bone scintigraphy, chest CT and chest MRI in 55 cases of lung cancer. The sensitivity, specificity and accuracy of the detection of rib metastases were compared between imaging modalities on both a per-lesion and a per-patient basis. On a per-lesion basis, MRI sensitivity and accuracy were significantly higher than that of bone scintigraphy and CT (P<0.05). The sensitivities, specificities, and accuracy levels between CT and bone scintigraphy did not differ on either a per-lesion or per-patient basis (P>0.05). MRI appears to be superior for the detection of ribs metastases in lung cancer.

Guidelines for the role of FDG-PET/CT in lung cancer management

Fluoro-2-deoxy-d-glucose (FDG)-positron emission tomography (PET) and PET/computed tomography (FDG-PET/CT) is regarded as a standard of care in the management of non-small-cell lung carcinoma (NSCLC) and is a useful adjunct in the characterization of indeterminate solitary lung nodules (SLN), and pre-treatment staging of NSCLC, notably mediastinal nodal staging and detection of remote metastases. FDG-PET/CT has the ability to assess locoregional lymph node spread more precisely than CT, to detect metastatic lesions that would have been missed on conventional imaging or are located in difficult areas, and to help in the differentiation of lesions that are equivocal after conventional imaging. Increasingly FDG-PET/CT is employed in radiotherapy planning, prediction of prognosis in terms of tumor response to neo-adjuvant, radiation and chemotherapy treatment. Evidence is accumulating of usefulness of PET/CT in small cell lung cancer.

Guidelines for multimodality radiological staging of lung cancer

Lung cancer is among the most common type of cancers and is a leading cause of cancer-related deaths with smoking representing the leading risk factor. It is classified into non-small cell lung cancer (NSCLC) representing 70-80% of cases and small cell lung cancer (SCLC) which has neuroendocrine properties with poor outcome. Staging of NSCLC is based on the TNM classification system while SCLC was usually classified into limited and extensive disease, though the use of TNM staging system for SCLC is recommended. Imaging studies are used to determine the pre-operative staging of lung cancer. Accurate radiological staging is essential to determine tumor resectability as well as to avoid futile surgeries and to assess patient's outcome. Moreover, radiological examinations are used for the evaluation of tumor response to treatment. This manuscript will review the utilization of imaging studies in the management of lung cancer based on the most recent guidelines by the National Comprehensive Cancer Network (NCCN).

Performance of whole-body PET/CT for the detection of distant malignancies in various cancers: a systematic review and meta-analysis

At present, there is no ideal imaging modality for the diagnosis of distant metastases and second primary cancers in cancer patients. We aimed to assess the accuracy of whole-body PET/CT for the overall assessment of distant malignancies in patients with various cancers.

METHODS

Studies about whole-body PET/CT for the detection of distant malignancies in cancer patients were systematically searched in MEDLINE and EMBASE. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios, and constructed summary receiver operating characteristic curves using hierarchical regression models for whole-body PET/CT.

RESULTS

Across 41 studies (4,305 patients), the sensitivity and specificity of whole-body PET/CT were 0.93 (95% confidence interval [CI], 0.88-0.96) and 0.96 (95% CI, 0.95-0.96), respectively. Subgroup analysis showed that the sensitivity and specificity of whole-body PET/CT for various cancers, respectively, were as follows: head and neck cancer, 0.90 (95% CI, 0.83-0.95) and 0.95 (95% CI, 0.94-0.96); lung cancer, 0.91 (95% CI, 0.76-0.97) and 0.96 (95% CI, 0.94-0.98); breast cancer, 0.97 (95% CI, 0.93-0.99) and 0.95 (95% CI, 0.90-0.97); and cancer of digestive system, 0.92 (95% CI, 0.68-0.98) and 0.97 (95% CI, 0.91-0.99).

CONCLUSION

Whole-body PET/CT has excellent diagnostic performance for the overall assessment of distant malignancies in patients with various cancers, especially head and neck cancer, breast cancer, and lung cancer.

The efficacy of PET staging for small-cell lung cancer: a systematic review and cost analysis in the Australian setting

INTRODUCTION

This study aimed to establish from the published literature the efficacy of a positron emission tomography (PET)-based strategy for the staging of small-cell lung cancer compared to conventional methods, the potential impact on patient management and outcomes, and cost implications for the Australian health system.

METHODS

EMBASE, Current Contents, PubMed, and OVID, databases were searched using relevant search terms. Reference lists of identified studies were examined for additional pertinent papers. Literature review identified 22 relevant studies containing data for 1663 patients. Studies were evaluated regarding the adequacy of pathological or clinical correlation of imaging findings. Efficacy of PET-staging was analyzed. The Medicare benefits schedule was used to compare costs of the two strategies.

RESULTS

Published data confirm that PET staging has a sensitivity approaching 100% and specificity exceeding 90%. Data suggest that compared to conventional staging, PET can alter management (including radiotherapy portal changes) in at least 28% of patients, can result in the addition of life-prolonging radiotherapy in 6%, and avert unnecessary radiotherapy with associated toxicity in 9%. PET-based staging costs 1603 Australian dollars (AUD) and conventional staging 1610 AUD per patient. An additional 540,354 AUD may be saved annually through avoidance of unnecessary radiotherapy.

CONCLUSIONS

PET-based staging seems superior to conventional staging, and can significantly alter patient management particularly with regard to the inclusion, omission, and portal design of radiotherapy. The initial costs of the two strategies do not seem significantly different. PET may ultimately reduce healthcare costs through avoidance of inappropriate thoracic radiotherapy. The major advantages of PET-staging may, however, lie in averting unnecessary toxicity and in the appropriate addition of thoracic radiotherapy with potential survival gains.

The role of integrated 18F-FDG PET-CT as a staging tool for limited-stage small cell lung cancer: a retrospective study

BACKGROUND

The aim of this study was to evaluate whether positron emission tomography-computed tomography (PET-CT) could be used as part of the staging work-up in patients with limited-stage disease (LD) small cell lung cancer (SCLC).

PATIENTS AND METHODS

Between January 2002 and December 2007, a total of 73 patients with presumed LD on CT, who underwent a PET-CT scan, were included in this study.

RESULTS

Conventional work-up revealed distant metastases in 12 patients. Out of 61 patients diagnosed as LD SCLC, PET-CT found unexpected distant metastases in 15 (24.6%) patients (LD/extensive-stage disease (ED)) of whom 13 (21.3%) were upstaged as a consequence. In 10 (76.9%) of the 13 upstaged patients, treatment was changed. The median survival of LD/LD SCLC patients who underwent concurrent chemoradiotherapy and chemotherapy only was 21.9 and 17.5 months, respectively. The median survival of LD/ED and ED/ED SCLC patients who received chemotherapy only was 17.4 and 14.1 months, respectively. The median survival of LD/LD SCLC patients who received concurrent chemoradiotherapy was superior to that of LD/ ED and ED/ED patients who received chemotherapy only (p = 0.037 and 0.004, respectively).

CONCLUSION

The addition of PET-CT seems to allow more accurate staging and may thus protect a percentage of SCLC patients from potentially futile and toxic radiotherapy.

Comparison of diagnostic ability between (99m)Tc-MDP bone scan and (18)F-FDG PET/CT for bone metastasis in patients with small cell lung cancer

OBJECTIVE

The aim of this study was to compare the diagnostic ability of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) with that of (99m)Tc-methylene diphosphonate ((99m)Tc-MDP) bone scan for bone metastasis in staging patients with small cell lung cancer (SCLC).

METHODS

Ninety-five patients with SCLC who underwent both (18)F-FDG PET/CT and (99m)Tc-MDP bone scan for initial staging work-up were retrospectively enrolled. All (18)F-FDG PET/CT and bone scan images were visually assessed. Bone metastasis was confirmed by histopathological results and all available clinical information.

RESULTS

Of 95 patients with SCLC, metastatic bone lesions were found in 30 patients, and 84 metastatic lesions were evaluated on a lesion-basis analysis. The sensitivity of (18)F-FDG PET/CT was 100 % on a per-patient basis and 87 % on a per-lesion basis, and there was no false-positive lesion on PET/CT images. In contrast, the sensitivity of the bone scan was 37 % on a per-patient basis and 29 % on a per-lesion basis. The bone scan showed 11 false-positive lesions. The bone scan detected two metastatic lesions that were not detected by PET/CT, which were outside the region scanned by PET/CT. On follow-up bone scan, 21 lesions that were not detected by the initial bone scan but were detected by PET/CT were newly detected.

CONCLUSIONS

In patients with SCLC, (18)F-FDG PET/CT showed higher detection rate of bone metastasis than (99m)Tc-MDP bone scan. Thus, (18)F-FDG PET/CT can replace bone scan in staging patients with SCLC.

Surgical intervention for small-cell lung cancer: what is the surgical role?

Small-cell lung cancer (SCLC) is an aggressive neuroendocrine carcinoma that accounts for approximately 10–15 % of all lung cancer cases. This histological subtype is a distinct entity with biological and oncological features differing from non-small cell lung cancer (NSCLC). Treatment is mainly performed using systemic chemotherapy, although surgery in association with chemotherapy may be indicated for a minor proportion of limited-disease cases. Since the outcomes after surgical intervention in patients with very early disease are comparable to those for NSCLC, accurate clinical staging is required, particularly in terms of nodal involvement. In addition to conventional mediastinoscopy, positron emission tomography-computed tomography and endobronchial ultrasonography guided transbronchial needle aspiration have recently become available for node diagnosis. The significance of surgery for SCLC includes local disease control and treatment for cases showing mixed histology. However, only two randomized control studies have examined the efficacy of surgery in SCLC, and both yielded negative results and are out of date. We review herein several studies concerning surgery for SCLC and discuss the results from a practical standpoint. A prospective trial performed in collaboration with pulmonologists is required to address the significance of surgery, which is a limited option in the treatment of SCLC.

Use of FDG-PET in Radiation Treatment Planning for Thoracic Cancers

Radiotherapy plays an important role in the treatment for thoracic cancers. Accurate diagnosis is essential to correctly perform curative radiotherapy. Tumor delineation is also important to prevent geographic misses in radiotherapy planning. Currently, planning is based on computed tomography (CT) imaging when radiation oncologists manually contour the tumor, and this practice often induces interobserver variability. F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) has been reported to enable accurate staging and detect tumor extension in several thoracic cancers, such as lung cancer and esophageal cancer. FDG-PET imaging has many potential advantages in radiotherapy planning for these cancers, because it can add biological information to conventional anatomical images and decrease the inter-observer variability. FDG-PET improves radiotherapy volume and enables dose escalation without causing severe side effects, especially in lung cancer patients. The main advantage of FDG-PET for esophageal cancer patients is the detection of unrecognized lymph node or distal metastases. However, automatic delineation by FDG-PET is still controversial in these tumors, despite the initial expectations. We will review the role of FDG-PET in radiotherapy for thoracic cancers, including lung cancer and esophageal cancer.

Staging and imaging of small cell lung cancer

Small cell lung cancer (SCLC) has been primarily classified as limited or extensive, with limited stage confined to the primary tumor and regional lymph nodes. In the future, the TNM staging system should be integrated into the classification of SCLC. The appropriate staging work-up for patients with SCLC has traditionally included contrast-enhanced computed tomography (CT) scans of the chest and abdomen, bone scan, and magnetic resonance imaging or CT scan of the brain. Recent data suggest that positron emission tomography can improve both staging accuracy and treatment planning in patients with SCLC. Treatment for limited-stage SCLC consists of chemotherapy plus radiotherapy, and such therapy can cure 20-25% of patients. Extensive-stage SCLC is incurable, but chemotherapy can improve quality of life and prolong life.

PET scans in radiotherapy planning of lung cancer

Accurate delineation of the primary tumor and of involved lymph nodes is a key requisite for successful curative radiotherapy in non-small cell lung cancer (NSCLC). In recent years, it has become clear that the incorporation of FDG PET-CT scan information into the related processes of patient selection and radiotherapy planning has lead to significant improvements for patients with NSCLC. The use of FDG PET-CT information in radiotherapy planning allows better target volume definition, reduces inter-observer variability and encourages selective irradiation of involved mediastinal lymph nodes. PET-CT also opens the door for innovative radiotherapy delivery and the development of new concepts. However, care must be taken to avoid a variety of technical pitfalls and specific education is necessary, for clinicians and physicists alike.

1st ESMO Consensus Conference in lung cancer; Lugano 2010: small-cell lung cancer

The 1st ESMO Consensus Conference on lung cancer was held in Lugano, Switzerland on 21st and 22nd May 2010 with the participation of a multidisciplinary panel of leading professionals in pathology and molecular diagnostics and medical, surgical and radiation oncology. Before the conference, the expert panel prepared clinically relevant questions concerning five areas as follows: early and locally advanced non-small-cell lung cancer (NSCLC), first-line metastatic NSCLC, second-/third-line NSCLC, NSCLC pathology and molecular testing, and small-cell lung cancer (SCLC) to be addressed through discussion at the Consensus Conference. All relevant scientific literature for each question was reviewed in advance. During the Consensus Conference, the panel developed recommendations for each specific question. The consensus agreement in SCLC is reported in this article. The recommendations detailed here are based on an expert consensus after careful review of published data. All participants have approved this final update.

Omitting elective nodal irradiation and irradiating postinduction versus preinduction chemotherapy tumor extent for limited-stage small cell lung cancer: interim analysis of a prospective randomized noninferiority trial

BACKGROUND

Controversies exist with regard to thoracic radiotherapy volumes for limited-stage small cell lung cancer (SCLC). This study compared locoregional progression and overall survival between limited-stage SCLC patients who received thoracic radiotherapy to different target volumes after induction chemotherapy.

METHODS

Chemotherapy consisted of 6 cycles of etoposide and cisplatin. After 2 cycles of etoposide and cisplatin, patients were randomly assigned to receive thoracic radiotherapy to either the postchemotherapy or prechemotherapy tumor extent as study arm or control. Elective nodal irradiation was omitted for both arms. Forty-five Gy/30Fx/19 days thoracic radiotherapy was administered concurrently with cycle 3 chemotherapy. Prophylactic cranial irradiation was administered to patients who achieved complete remission. An interim analysis was planned when the first 80 patients had been followed for at least 6 months, for consideration of potential inferiority in the study arm.

RESULTS

Forty-two and 43 patients were randomly assigned to a study arm and a control, respectively. The local recurrence rates were 31.6% (12 of 38) and 28.6% (12 of 42), respectively (P = .81). The isolated nodal failure rates were 2.6% (1 of 38) and 2.4% (1 of 42), respectively (P = 1.00). All isolated nodal failure sites were in the ipsilateral supraclavicular fossa. Mediastinal N3 was the only factor to predict isolated nodal failure (P = .004; odds ratio [OR], 29.33; 95% CI, 2.94-292.38). One-year and 3-year overall survival rates were 80.6%, 36.2%, and 78.9%, 36.4%, respectively (P = .54).

CONCLUSIONS

Preliminary results indicated that irradiated postchemotherapy tumor extent and omitted elective nodal irradiation did not decrease locoregional control in the study arm, and the overall survival difference was not statistically significant between the 2 arms. Further investigation is warranted.

Early CT and FDG-metabolic tumour volume changes show a significant correlation with survival in stage I-III small cell lung cancer: a hypothesis generating study

BACKGROUND

Many patients with stage I-III small cell lung cancer (SCLC) experience disease progression short after the completion of concurrent chemoradiotherapy (CRT). The purpose of the current study was to evaluate whether CT or FDG metabolic response early after the start of chemotherapy, but before the beginning of chest RT, is predictive for survival in SCLC.

METHODS

Fifteen stage I-III SCLC patients treated with concurrent CRT with an FDG-PET and CT scan available before the start of chemotherapy and after or during the first cycle of chemotherapy, but before the start of radiotherapy, were selected. The metabolic volume (MV) was defined both within the primary tumour and in the involved nodal stations using the 40% (MV40) and 50% (MV50) threshold of the maximum SUV. Metabolic and CT response was assessed by the relative change in MV and CT volume, respectively, between both time points. The association between response and overall survival (OS) was analysed by univariate cox regression analysis. The minimum follow-up was 18 months.

RESULTS

Reductions in MV40 and MV50 were -36±38% (126.4 to 68.7cm(3)) and -44±38% (90.2 to 27.8cm(3)), respectively. The median CT volume reduction was -40±64% (190.6 to 113.8cm(3)). MV40 and MV50 changes showed a significant association with survival (HR=1.02, 95% CI: 1.00-1.04 (p=0.042); HR=1.02, 95% CI: 1.00-1.04 (p=0.048), respectively), indicating a 2% increase in survival probability for 1% reduction in metabolic volume. The CT volume change was also significantly correlated with survival (HR=1.01, 95% CI: 1.00-1.03, p=0.007).

CONCLUSIONS

This hypothesis generating study shows that both the early CT and the MV changes show a significant correlation with survival in SCLC. A prospective study is planned in a larger patient cohort to allow multivariate analysis, with the final aim to select patients early during treatment that could benefit from dose intensification or alternative treatment.

PET/CT imaging in different types of lung cancer: an overview

Lung cancer (LC) still represents one of the most common tumours in both women and men. PET/CT is a whole-body non-invasive imaging procedure that has been increasingly used for the assessment of LC patients. In particular, PET/CT added value to CT is mainly related to a more accurate staging of nodal and metastatic sites and to the evaluation of the response to therapy. Although the most common PET tracer for LC evaluation is 18F-FDG, new tracers have been proposed for the evaluation of lung neuroendocrine tumours (68Ga-DOTA-peptides, 18F-DOPA) and for the assessment of central nervous system metastasis (11C-methionine). This review focuses on the main clinical applications and accuracy of PET/CT for the detection of non-small cells lung cancer (NSCLC), broncho-alveolar carcinoma (BAC), small cells lung cancer (SCLC), lung neuroendocrine tumours (NET) and solitary pulmonary nodules (SPN).

A meta-analysis of ¹⁸FDG-PET-CT, ¹⁸FDG-PET, MRI and bone scintigraphy for diagnosis of bone metastases in patients with lung cancer

BACKGROUND AND PURPOSE

Lung cancer is the most common cause of cancer related death among both men and women worldwide. The skeleton is the most common site of cancer metastasis. Early detection is crucial for prognosis. To evaluate and compare the capability for bone metastasis assessment of [(18)F] fluoro-2-d-glucose positron emission tomography with computed tomography ((18)FDG-PET-CT), [(18)F] fluoro-2-d-glucose positron emission tomography ((18)FDG-PET), magnetic resonance imaging (MRI) and bone scintigraphy (BS) in lung cancer patients, a meta-analysis is preformed.

METHODS

We searched MEDLINE, OVID, EMBASE and the Cochrane Library for studies evaluating diagnosis validity of (18)FDG-PET-CT, (18)FDG-PET, MRI and BS between January 1990 and August 2010. Meta-analysis methods were used to pool sensitivity, specificity, diagnostic odd ratios (DORs) and to construct a summary receiver-operating characteristic curve (SROC).

RESULTS

A total of 17 articles (9 (18)FDG-PET-CT studies, 9 (18)FDG-PET studies, 6 MRI studies and 16 BS studies) that included 2940 patients who fulfilled all of the inclusion criteria were considered for inclusion in the analysis. The pooled sensitivity for the detection of bone metastasis in lung cancer using (18)FDG-PET-CT, (18)FDG-PET, MRI and BS were 0.92 (95% CI, 0.88-0.95), 0.87 (95% CI, 0.81-0.92), 0.77 (95% CI, 0.65-0.87) and 0.86 (95% CI, 0.82-0.89), respectively. The pooled specificity for the detection of bone metastasis from lung cancer using (18)FDG-PET-CT, (18)FDG-PET, MRI and BS were 0.98 (95% CI, 0.97-0.98), 0.94 (95% CI, 0.92-0.96), 0.92 (95% CI, 0.88-0.95), 0.88 (95% CI, 0.86-0.89), respectively. The pooled DORs estimates for (18)FDG-PET-CT 449.17 were significantly higher than for (18)FDG-PET (118.25, P<0.001), MRI (38.27, P<0.001) and BS (63.37, P<0.001). The pooled sensitivity of BS was not correlated with the prevalence of bone metastasis.

CONCLUSION

The results showed that both (18)FDG-PET-CT and (18)FDG-PET were better imaging methods for diagnosing bone metastasis from lung cancer than MRI and BS. (18)FDG-PET-CT has higher diagnostic value (sensitivity, specificity and DORs) for diagnosing bone metastasis from lung cancer than any other imaging methods.

Therapeutic implications of molecular imaging with PET in the combined modality treatment of lung cancer

Molecular imaging with PET, and certainly integrated PET-CT, combining functional and anatomical imaging, has many potential advantages over anatomical imaging alone in the combined modality treatment of lung cancer. The aim of the current article is to review the available evidence regarding PET with FDG and other tracers in the combined modality treatment of locally advanced lung cancer. The following topics are addressed: tumor volume definition, outcome prediction and the added value of PET after therapy, and finally its clinical implications and future perspectives. The additional value of FDG-PET in defining the primary tumor volume has been established, mainly in regions with atelectasis or post-treatment effects. Selective nodal irradiation (SNI) of FDG-PET positive nodal stations is the preferred treatment in NSCLC, being safe and leading to decreased normal tissue exposure, providing opportunities for dose escalation. First results in SCLC show similar results. FDG-uptake on the pre-treatment PET scan is of prognostic value. Data on the value of pre-treatment FDG-uptake to predict response to combined modality treatment are conflicting, but the limited data regarding early metabolic response during treatment do show predictive value. The FDG response after radical treatment is of prognostic significance. FDG-PET in the follow-up has potential benefit in NSCLC, while data in SCLC are lacking. Radiotherapy boosting of radioresistant areas identified with FDG-PET is subject of current research. Tracers other than (18)FDG are promising for treatment response assessment and the visualization of intra-tumor heterogeneity, but more research is needed before they can be clinically implemented.

Impact of 18F-fluorodeoxyglucose positron emission tomography in the staging and treatment response assessment of extra-pulmonary small-cell cancer

The aim of this study was to retrospectively evaluate the value of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in extrapulmonary small-cell cancer (EPSCC). Patients with EPSCC who underwent PET for staging or response assessment between 1996 and 2007 were identified from a database. Patient records were reviewed. PET-based, and conventional staging and restaging results were compared. The binary staging classification of limited disease (LD) versus extensive disease (ED) was used. Patients with LD had tumours that could be encompassed within a tolerable radiation therapy (RT) volume. Of 33 eligible patients, 12 had staging PET scans, 11 had restaging scans and 10 had both. All known gross disease sites were FDG-avid. PET and conventional stage groupings were concordant in 21 of 22 cases. One patient was appropriately upstaged from LD to ED by PET. PET detected additional disease sites, without causing upstaging in three further patients. Restaging PET scans identified previously unrecognised persistent or progressive disease in 4 of 21 cases. In four further cases, persistent FDG uptake after treatment was either false positive (n = 2) or of uncertain (n = 2) aetiology. PPV was 100% for staging and 82% for restaging. In 8 of 43 imaging episodes (19%), PET appropriately influenced management in five cases by changing treatment intent from radical to palliative, and in three cases by altering the RT volume. PET has incremental value compared to conventional imaging for staging EPSCC, and may also be useful for restaging after therapy. PET influenced patient management in 19% of 43 imaging episodes.

[What is the role of FDG-PET in thoracic oncology in 2010?]

18F-Fluorodeoxyglucose-Positron Emission Tomography (FGD-PET) has been considered to have a major impact on the management of lung malignancies since the beginning of this century. Its value has been demonstrated by many publications, meta-analysis and European/American/Japanese recommendations. PET combined with computed tomography has provided useful information regarding the diagnosis and staging of lung cancer and allows for the delivery of adaptive radiotherapy. In its more common uses, PET has been shown to be cost-effective. With the widespread use of new radiotracers, PET will play an increasing role in the evaluation of response to treatment.

18-Fluorodeoxyglucose positron emission tomography as a tool for response prediction in solid tumours

Current response guidelines for the treatment of solid tumours are based on CT criteria. Over the last decades new techniques have emerged to evaluate cancer therapy. FDG-PET scanning is a more functional imaging technique, which can measure differences in metabolic activity. Although it has a low specificity, studies show that it can outperform classical CT scanning criteria. Especially in lung, breast and oesophageal cancer it can predict response earlier in the neo-adjuvant setting. This could reduce the use of ineffective cancer therapies, reducing costs and patient toxicity, and direct patients sooner towards effective therapy. The main problem with FDG-PET remains the difficulty in defining thresholds for response, as there is clearly a lack in large prospective randomized studies validating the use of FDG-PET in response guidelines.We give an overview of data on response prediction in solid tumours by the application of PET.

[A prospective randomized study of the radiotherapy volume for limited-stage small cell lung cancer: a preliminary report]

BACKGROUND AND OBJECTIVE

Controversies exists with regard to target volumes as far as thoracic radiotherapy (TRT) is concerned in the multimodality treatment for limited-stage small cell lung cancer (LSCLC). The aim of this study is to prospectively compare the local control rate, toxicity profiles, and overall survival (OS) between patients received different target volumes irradiation after induction chemotherapy.

METHODS

LSCLC patients received 2 cycles of etoposide and cisplatin (EP) induction chemotherapy and were randomly assigned to receive TRT to either the post- or pre-chemotherapy tumor extent (GTV-T) as study arm and control arm, CTV-N included the positive nodal drainage area for both arms. One to 2 weeks after induction chemotherapy, 45 Gy/30 Fx/19 d TRT was administered concurrently with the third cycle of EP regimen. After that, additional 3 cycles of EP consolidation were administered. Prophylactic cranial irradiation (PCI) was administered to patients with a complete response.

RESULTS

Thirty-seven and 40 patients were randomly assigned to study arm and control arm. The local recurrence rates were 32.4% and 28.2% respectively (P = 0.80); the isolated nodal failure (INF) rates were 3.0% and 2.6% respectively (P = 0.91); all INF sites were in the ipsilateral supraclavicular fossa. Medastinal N3 disease was the risk factor for INF (P = 0.02, OR = 14.13, 95% CI: 1.47-136.13). During radiotherapy, grade I, II weight loss was observed in 29.4%, 5.9% and 56.4%, 7.7% patients respectively (P = 0.04). Grade 0-I and II-III late pulmonary injury was developed in 97.1%, 2.9% and 86.4%, 15.4% patients respectively (P = 0.07). Median survival time was 22.1 months and 26.9 months respectively. The 1 to 3-year OS were 77.9%, 44.4%, 37.3% and 75.8%, 56.3%, 41.7% respectively (P = 0.79).

CONCLUSIONS

The preliminary results of this study indicate that irradiant the post-chemotherapy tumor extent (GTV-T) and positive nodal drainage area did not decrease local control and overall survival while radiation toxicity was reduced. But the current sample size has not met designed requirements, and further investigation is warranted before final conclusions could be drawn.

PET and PET-CT in radiation treatment planning for lung cancer

This review analyzes PET images in radiotherapy treatment planning for lung cancer patients and discusses the most controversial current issues. Computed tomography images are commonly used to assess location and extension of target volumes and organs at risk in radiotherapy treatment planning. Although PET is more sensitive and specific, contouring on PET images is difficult because tumor margins are indistinct, due to heterogeneous (18)fluorodeoxyglucose uptake distribution and limited spatial resolution. The best target delineation criteria have not yet been established. In non-small-cell lung cancer, PET appears to improve sparing of organs at risk and reduce the risk of toxicity; prescribed doses can be increased. Data are scarce on small-cell lung cancer.

Soluble adhesion molecules E-cadherin, intercellular adhesion molecule-1, and E-selectin as lung cancer biomarkers

BACKGROUND

Altered levels of circulating adhesion molecules found in several carcinomas, including lung cancer, reflect local loss of diffusion barriers and tumor volume and can be potentially used as biomarkers. In the present study, we investigated the role of soluble E-cadherin (sE-cad), soluble intercellular adhesion molecule-1 (sICAM-1), and soluble E-selectin (sE-sel) as biomarkers in lung cancer.

METHODS

Sixty-two patients with recently diagnosed lung cancer, 42 with small cell lung cancer (SCLC), and 20 with non-small cell lung cancer (NSCLC), as well as 29 healthy volunteers were enrolled. Blood samples were collected at the time of diagnosis and measurement of soluble adhesion molecules in the serum samples was performed by enzyme-linked immunoassay using monoclonal antibodies against E-cadherin, E-selectin, and ICAM-1.

RESULTS

Serum levels of sE-cad, sE-sel, and sICAM-1 in both SCLC and NSCLC were significantly elevated compared with control subjects (P < .001). In addition, patients with SCLC or NSCLC with distant metastasis had a marked increase of sE-Cad (P < .001), but no such correlation with sE-sel and sICAM-1 was found.

CONCLUSIONS

Our findings suggest that sE-cad, sE-sel, and sICAM-1 have an adjunctive diagnostic role in lung cancer. Furthermore, sE-cad may also have a prognostic role and could be a useful biomarker in the prediction of lung cancer outcome.

High impact of 18F-FDG-PET on management and prognostic stratification of newly diagnosed small cell lung cancer

PURPOSE

We evaluated whether 18F-FDG-PET altered stage classification, management, and prognostic stratification of newly diagnosed small cell lung cancer (SCLC).

PROCEDURES

We identified 46 consecutive patients undergoing staging positron emission tomography for SCLC from 1993-2008 inclusive. Updated survival data from the state Cancer Registry was available on 42 of 46 patients.

RESULTS

PET altered stage classification in 12 of 46 (26%) patients. PET altered treatment modality in nine patients, and the target mediastinal radiation field in another three patients. Therefore, PET altered management in 12 of 46 (26%) patients. Patients with limited disease (LD) on pre-PET staging had significantly longer overall survival (OS) than those upstaged to extensive disease (ED; median 18.6 months versus 5.7 months; log-rank p < 0.0001). In patients with ED on pre-PET staging, those downstaged to LD by PET had significantly longer OS than those with ED on PET (median 10.9 months versus 5.9 months; log-rank p = 0.037).

CONCLUSION

PET had a major impact on stage classification, management, and prognostic stratification of newly diagnosed SCLC.

Selective nodal irradiation on basis of (18)FDG-PET scans in limited-disease small-cell lung cancer: a prospective study

PURPOSE

To evaluate the results of selective nodal irradiation on basis of (18)F-deoxyglucose positron emission tomography (PET) scans in patients with limited-disease small-cell lung cancer (LD-SCLC) on isolated nodal failure.

METHODS AND MATERIALS

A prospective study was performed of 60 patients with LD-SCLC. Radiotherapy was given to a dose of 45 Gy in twice-daily fractions of 1.5 Gy, concurrent with carboplatin and etoposide chemotherapy. Only the primary tumor and the mediastinal lymph nodes involved on the pretreatment PET scan were irradiated. A chest computed tomography (CT) scan was performed 3 months after radiotherapy completion and every 6 months thereafter.

RESULTS

A difference was seen in the involved nodal stations between the pretreatment (18)F-deoxyglucose PET scans and computed tomography scans in 30% of patients (95% confidence interval, 20-43%). Of the 60 patients, 39 (65%; 95% confidence interval [CI], 52-76%) developed a recurrence; 2 patients (3%, 95% CI, 1-11%) experienced isolated regional failure. The median actuarial overall survival was 19 months (95% CI, 17-21). The median actuarial progression-free survival was 14 months (95% CI, 12-16). 12% (95% CI, 6-22%) of patients experienced acute Grade 3 (Common Terminology Criteria for Adverse Events, version 3.0) esophagitis.

CONCLUSION

PET-based selective nodal irradiation for LD-SCLC resulted in a low rate of isolated nodal failures (3%), with a low percentage of acute esophagitis. These findings are in contrast to those from our prospective study of CT-based selective nodal irradiation, which resulted in an unexpectedly high percentage of isolated nodal failures (11%). Because of the low rate of isolated nodal failures and toxicity, we believe that our data support the use of PET-based SNI for LD-SCLC.