Metastases from non-small cell lung cancer: mediastinal staging in the 1990s--meta-analytic comparison of PET and CT

Role of fusion in radiotherapy treatment planning

The fusion of functional imaging to traditional imaging modalities, such as computed tomography (CT) and magnetic resonance imaging (MRI), is currently being investigated in radiotherapy treatment planning. Most studies that have been reported are in patients with lung, brain, or head and neck neoplasms. There is a potential role for either positron emission tomography (PET) or single photon emission computed tomography (SPECT) to delineate biologically active or tumor-bearing areas that otherwise would not be detected by CT or MRI. Furthermore, target volumes may be modified by using functional imaging, which can have a significant impact in the modern era of three-dimensional radiotherapy. SPECT may also be able to identify "nonfunctional" surrounding tissue and may influence radiotherapy beam arrangement.

Staging of non-small-cell lung cancer with integrated positron-emission tomography and computed tomography

BACKGROUND

We compared the diagnostic accuracy of integrated positron-emission tomography (PET) and computed tomography (CT) with that of CT alone, that of PET alone, and that of conventional visual correlation of PET and CT in determining the stage of disease in non-small-cell lung cancer.

METHODS

In a prospective study, integrated PET-CT was performed in 50 patients with proven or suspected non-small-cell lung cancer. CT and PET alone, visually correlated PET and CT, and integrated PET-CT were evaluated separately, and a tumor-node-metastasis (TNM) stage was assigned on the basis of image analysis. Nodal stations were identified according to the mapping system of the American Thoracic Society. The standard of reference was histopathological assessment of tumor stage and node stage. Extrathoracic metastases were confirmed histopathologically or by at least one other imaging method. A paired sign test was used to compare integrated PET-CT with the other imaging methods.

RESULTS

Integrated PET-CT provided additional information in 20 of 49 patients (41 percent), beyond that provided by conventional visual correlation of PET and CT. Integrated PET-CT had better diagnostic accuracy than the other imaging methods. Tumor staging was significantly more accurate with integrated PET-CT than with CT alone (P=0.001), PET alone (P<0.001), or visual correlation of PET and CT (P=0.013); node staging was also significantly more accurate with integrated PET-CT than with PET alone (P=0.013). In metastasis staging, integrated PET-CT increased the diagnostic certainty in two of eight patients.

CONCLUSIONS

Integrated PET-CT improves the diagnostic accuracy of the staging of non-small-cell lung cancer.

The value of chest computer tomography and cervical mediastinoscopy in the preoperative assessment of patients with malignant pleural mesothelioma

BACKGROUND

Patients with localized malignant pleural mesothelioma (MPM) can be considered for surgical resection with or without additional treatment. For this approach it is imperative to select patients without mediastinal lymph node involvement. In this study cervical mediastinoscopy (CM) is compared with computer tomography (CT) scanning for its diagnostic accuracy in assessing mediastinal lymph nodes during preoperative workup.

METHODS

Computer tomography scans of the chest and CM were performed in 43 patients with proven unilateral MPM. The CT scans were reviewed by one radiologist and two chest physicians. At CM the lymph node samples were taken from stations Naruke 2, 3, 4, and 7. Computer tomography and CM results were compared with final histopathologic findings obtained at thoracotomy or, if this was not performed, at CM.

RESULTS

Computer tomography scanning revealed pathologic enlarged lymph nodes with a shortest diameter of at least 10 mm in 17 of 43 patients (39%). There was histopathologic evidence of lymph node metastases at CM in 11 of these patients (26%). This resulted in a sensitivity of 60% and 80%, a specificity of 71% and 100%, and a diagnostic accuracy of 67% and 93% for CT and CM, respectively.

CONCLUSIONS

Cervical mediastinoscopy is a valuable diagnostic procedure for patients with MPM who are considered candidates for surgical-based therapy. Results of CM are more reliable than those obtained by CT scanning. Our data confirm results of previous studies reporting that mediastinal lymph node involvement is a frequent event in MPM.

Alterations of tumor suppressor genes (Rb, p16, p27 and p53) and an increased FDG uptake in lung cancer

OBJECTIVE

The FDG uptake in lung cancer is considered to reflect the degree of malignancy, while alterations of some tumor suppressor genes are considered to be related to the malignant biological behavior of tumors. The aim of this study is to examine the relationship between FDG-PET and alterations in the tumor suppression genes of lung cancer.

METHODS

We examined 28 patients with primary lung cancer who underwent FDG-PET before surgery consisting of 17 patients with adenocarcinoma, 10 with squamous cell carcinoma and 1 with large cell carcinoma. The FDG-PET findings were evaluated based on the standardized uptake value (SUV). Alterations in the tumor suppressor genes, Rb, p16, p27 and p53, were evaluated immunohistochemically.

RESULTS

The FDG uptake in lung cancer with alteration in each tumor suppressor gene tended to be higher than in those genes without alterations, although the differences were not significant. In 15 tumors with alterations in either tumor suppressor genes, the FDG uptake was 6.83 +/- 3.21. On the other hand, the mean FDG uptake was 1.95 in 2 tumors without alterations in any genes. The difference in the FDG uptake between the 2 groups was statistically significant (p < 0.001).

CONCLUSIONS

In conclusion, the presence of abnormalities in the tumor suppressor genes, which results in an accelerated cell proliferation, is thus considered to increase the FDG uptake in lung cancer.

Clinical applications of FDG-PET in oncology

Positron emission tomography together with F-18-deoxyglucose (FDG) has emerged as a valuable clinical tool in the field of oncology. FDG-PET diagnoses, stages and restages most cancers with a high diagnostic accuracy. The effects of chemotherapy on tumour metabolism can be monitored with this whole-body technique. Recent studies have established a high prognostic accuracy of PET for predicting the clinical outcome of cancer patients. The current review addresses the role of FDG-PET for diagnosing, staging and restaging of lung cancer, colorectal cancer, lymphoma, melanoma and breast cancer staging and provides a brief outlook for future applications of clinical PET imaging.

Value of whole-body FDG PET in management of lung cancer

18F-fluorodeoxyglucose (FDG) PET imaging provides physiologic and metabolic information that characterizes lesions that are indeterminate by CT. FDG PET imaging is sensitive to the detection of lung cancer in patients who have indeterminate lesions on CT, whereas low grade malignancy such as bronchioloalveolar carcinoma and carcinoid may be negative on FDG PET. The specificity of PET imaging is less than its sensitivity because some inflammatory processes, such as active granulomatous infections, avidly accumulate FDG. This possibility should be kept in mind in the analysis of PET studies of glucose metabolism aimed at differentiating malignant from benign solitary pulmonary nodules. FDG uptake is considered to be a good marker of cell differentiation, proliferative potential, aggressiveness, and the grade of malignancy in patients with lung cancer. FDG PET accurately stages the distribution of lung cancer. Several studies have documented the increased accuracy of PET compared with CT in the evaluation of the hilar and mediastinal lymphnode status in patients with lung cancer. Whole-body PET studies detect metastatic disease that is unsuspected by conventional imaging. Management changes have been reported in up to 41% of patients on the basis of the results of whole-body studies. Whole-body FDG PET is also useful for the detection of recurrence. Several studies have indicated that the degree of FDG uptake in primary lung cancer can be used as an independent prognostic factor. Thus, whole-body FDG PET is clinically very useful in the management of lung cancer.

Cytologic approach to tumors of the tracheobronchial tree

Cytologic testing is an integral part of the workup of patients suspected of having lung cancer. These tests are less invasive than other tissue procurement methods, with minimal risk of complications. In experienced hands, the tests are highly accurate and reliable. To achieve good results and avoid diagnostic errors, clinicians must be educated in proper collection and fixation methods and the pathologist should be cognizant of clinical and radiologic data. Close communication between the clinician and pathologist should be encouraged.

Thymic enlargement and FDG uptake in three patients: CT and FDG positron emission tomography correlated with pathology

OBJECTIVE

Our purpose was to describe three adult patients in whom we found increased thymic uptake of FDG on positron emission tomography and thymic enlargement with convex lateral margins on CT. Subsequent biopsy or resection showed normal thymic tissue.

CONCLUSION

In three adults, we found a physiologic uptake of FDG by the thymus with standardized uptake values in the range of thymic neoplasia.

Classification, staging and prognosis of lung cancer

Lung cancer has increased in incidence throughout the twentieth century and is now the most common cancer in the Western World. It has a poor prognosis, only 10-15% of patients survive 5 years or longer. Outcome is dependent on clinical stage and cancer cell type. Lung cancer is broadly subclassified on the basis of histological features into squamous cell carcinoma, adenocarcinoma, large cell carcinoma and small cell carcinoma. The histopathological type of lung cancer correlates with tumour behaviour and prognosis. Staging based on prognosis is essential in clinical trials comparing different management strategies, and enables universal communication regarding the efficacy of different treatments in specific patient groups. The anatomic extent of disease determined either preoperatively using imaging supplemented by invasive procedures such as mediastinoscopy, and anterior mediastinotomy or following resection are described according to the T-primary tumour, N-regional lymph nodes, M-distant metastasis classification. The International System for Staging Lung Cancer attempts to group together patients with similar prognosis and treatment options. Various combinations of T, N, and M define different clinical or surgical-pathological stages (IA-IV) characterised by different survival characteristics. Refinements in staging based on imaging findings have enabled clinical staging to more accurately reflect the surgical-pathological stage and therefore more accurately predict prognosis. Recent advances including the use of positron emission tomography in combination with conventional staging promises to increase the accuracy of staging and therefore to reduce the number of invasive staging procedures and inappropriate thoracotomies.

Prospective use of serial questionnaires to evaluate the therapeutic efficacy of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in suspected lung cancer

BACKGROUND

A study was undertaken to study the effect of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) on the diagnosis and management of clinically problematic patients with suspected non-small cell lung cancer (NSCLC).

METHODS

A prospective before-after study was performed in a cohort of all 164 patients (university/community settings) referred for PET between August 1997 and July 1999. PET was restricted to cases where non-invasive tests had failed to solve clinical problems. The impact on diagnostic understanding and management was assessed using questionnaires (intended treatment without PET, actual treatment choice after PET, post hoc clinical assessment).

RESULTS

Diagnostic problems especially pertained to unclear radiological findings (n=112; 63%), mediastinal staging (n=36; 20%), and distant staging issues (n=16; 9%). PET findings were validated by reviewing medical records. PET had a positive influence on diagnostic understanding in 84%. Improved diagnostic understanding solely based on PET was reported in 26%. According to referring physicians, PET resulted in beneficial change of treatment in 50%. Cancelled surgery was the most frequent change in treatment after PET (35%).

CONCLUSION

FDG PET applied as "add on" technology in patients with these clinical problems appears to be a clinically useful tool, directly improving treatment choice in 25% of patients. The value of increased confidence induced by PET scanning requires further evaluation.

Staging of non-small cell lung cancer: imaging of intrathoracic disease

This article reviews the contribution of diagnostic imaging to the intrathoracic staging of non-small cell lung cancer. The principle features of the current staging system are discussed along with the relative roles of the various imaging modalities in the evaluation of the primary tumour and metastatic disease. The emerging role of positron emission tomography with fluorodeoxyglucose (FDG-PET) as a clinically useful, potentially cost effective, complementary imaging technique is also reviewed.

Noninvasive staging of non-small cell lung cancer: a review of the current evidence

STUDY OBJECTIVES

To determine the test performance characteristics of CT scanning, positron emission tomography (PET) scanning, MRI, and endoscopic ultrasound (EUS) for staging the mediastinum, and to evaluate the accuracy of the clinical evaluation (ie, symptoms, physical findings, or routine blood test results) for predicting metastatic disease in patients in whom non-small cell lung cancer or small cell lung cancer is diagnosed.

DESIGN, SETTING, AND PARTICIPANTS

Systematic searches of MEDLINE, HealthStar, and Cochrane Library databases to July 2001, and of print bibliographies. Studies evaluating the staging results of CT scanning, PET scanning, MRI, or EUS, with either tissue histologic confirmation or long-term clinical follow-up, were included. The performance of the clinical evaluation was compared against the results of brain and abdominal CT scans and radionuclide bone scans.

MEASUREMENT AND RESULTS

Pooled sensitivities and specificities for staging the mediastinum were as follows: for CT scanning: sensitivity, 0.57 (95% confidence interval [CI], 0.49 to 0.66); specificity, 0.82 (95% CI, 0.77 to 0.86); for PET scanning: sensitivity, 0.84 (95% CI, 0.78 to 0.89); specificity, 0.89 (95% CI, 0.83 to 0.93); and for EUS: sensitivity, 0.78 (95% CI, 0.61 to 0.89); specificity, 0.71 (95% CI, 0.56 to 0.82). For the evaluation of brain metastases, the summary estimate of the negative predictive value (NPV) of the clinical neurologic evaluation was 0.94 (95% CI, 0.91 to 0.96). For detecting adrenal and/or liver metastases, the summary NPV of the clinical evaluation was 0.95 (95% CI, 0.93 to 0.96), and for detecting bone metastases, it was 0.90 (95% CI, 0.86 to 0.93).

CONCLUSIONS

PET scanning is more accurate than CT scanning or EUS for detecting mediastinal metastases. The NPVs of the clinical evaluations for brain, abdominal, and bone metastases are > or = 90%, suggesting that routinely imaging asymptomatic lung cancer patients may not be necessary. However, more definitive prospective studies that better define the patient population and improved reference standards are necessary to more accurately assess the true NPV of the clinical evaluation.

Value of FDG-PET in the management of non-small cell lung cancer

In the past 5 years, metabolic imaging with positron emission tomography (PET) using 18F-fluoro-2-deoxy-glucose (FDG) has become an important imaging modality in lung cancer patients. FDG-PET consistently proved to be superior to structure-based imaging modalities in both the diagnosis and staging of lung cancer. At this moment the use of FDG-PET in these indications needs further validation in multi-centre large-scale randomised studies, focusing mainly on treatment outcome parameters, survival and cost-efficacy. More recently, interesting findings have also been reported in the response assessment to cytotoxic treatments providing information of greater prognostic significance than can be obtained using conventional approaches. This review focuses on the potential role of FDG-PET in the diagnosis of lung nodules and masses, and in locoregional and extrathoracic staging of non-small cell lung cancer. Emphasis is put on the potential clinical implementation of the numerous data of the last decade.

Mediastinal lymph node staging in suspected lung cancer: comparison of positron emission tomography with F-18-fluorodeoxyglucose and mediastinoscopy

BACKGROUND

In patients with bronchogenic carcinoma, mediastinal lymph node staging is essential for determining treatment options. In this retrospective analysis we compared the results of positron emission tomography (PET) using F-18 fluorodeoxyglucose with those of mediastinoscopy in nodal staging for suspected bronchogenic carcinoma.

METHODS

From March 1997 to June 2001, 102 patients (86 male,16 female, age 62 +/- 9 years) underwent both PET and mediastinoscopy for radiologically suspected mediastinal lymph node disease in bronchogenic carcinoma. Total body emission scans were acquired 90 to 150 minutes after injection of 230 MBq of F-18 fluorodeoxyglucose. Mediastinoscopic evaluation of lymph node stations was performed according to the method of Mountain and Dresler (1R, 1L, 2L, 2R, 4L, 4R,7). Patients were eligible if surgical staging was performed within 6 weeks after the PET scan. RESULTS. Of the 102 patients, benign lesions were diagnosed in 15. In 87 patients malignant disease was proven by histology, and bronchogenic carcinoma was found in 82. Of 469 nodal stations analyzed, malignancy was documented by histology in 84. In PET analysis 79 true-positive and 304 true-negative samples were found. Five lymph node stations were false negative, and 81 samples were false positive. False-positive findings in PET frequently were seen in inflammatory lung disease. The sensitivity of PET was 94.1%, specificity was 79% with a diagnostic accuracy of 81.6%. The positive predictive value of PET was 49.3%, and the negative predictive value was 98.4%.

CONCLUSIONS

In patients with positive PET scan results histologic verification appears necessary for exact lymph node staging. In view of the negative predictive value mediastinoscopy can be omitted in patients with bronchogenic carcinoma whose PET scan results were negative.

Early lung cancer detection and treatment strategies

Lung cancer is the leading cause of cancer deaths in both men and women in the United States. The majority of lung cancer patients will present with advanced disease with a very poor overall survival. Although prior screening trials have shown no benefit from screening, there is renewed interest in low dose CT scanning as a screening modality for lung cancer. A high proportion of screen-detected cancers are early stage and resectable for cure. For the majority of these early stage patients, standard lobectomy is the treatment of choice. New options to potentially detect and treat early stage lung cancer will increase dramatically in the future.

Dose-response relationship between probability of pathologic tumor control and glucose metabolic rate measured with FDG PET after preoperative chemoradiotherapy in locally advanced non-small-cell lung cancer

PURPOSE

To determine the dose-response relationship between the probability of tumor control on the basis of pathologic tumor response (pTCP) and the residual metabolic rate of glucose (MRglc) in response to preoperative chemoradiotherapy in locally advanced non-small-cell lung cancer and to define the level of residual MRglc that corresponds to pTCP 50% and pTCP > or = 95%.

METHODS AND MATERIALS

Quantitative dynamic 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography was performed to measure regional MRglc at the primary lesion before and 2 weeks after preoperative chemoradiotherapy in an initial group of 13 patients with locally advanced NSCLC. A simplified kinetic method was developed subsequently from the initial dynamic study and used in the subsequent 16 patients. The preoperative radiotherapy programs consisted of (1) a split course of 42 Gy in 28 fractions within a period of 28 days using a twice-daily treatment schedule for Stage IIIA(N2) NSCLC (n = 18) and (2) standard once-daily radiation schedule of 45-63 Gy in 25-35 fractions during a 5-7-week period (n = 11). The preoperative chemotherapy regimens included two cycles of cisplatin, vinblastine, and 5-fluorouracil (n = 24), cisplatin and etoposide (n = 2), and cisplatin, Taxol, and 5-fluorouracil (n = 3). Patients free of tumor progression after preoperative chemoradiotherapy underwent surgery. The degree of residual MRglc measured 2 weeks after preoperative chemoradiotherapy and 2 weeks before surgery was correlated with the pathologic tumor response. The relationship between MRglc and pTCP was modeled using logistic regression.

RESULTS

Of 32 patients entered into the study, 29 (16 men and 13 women; 30 lesions) were evaluated for the correlation between residual MRglc and pathologic tumor response. Three patients did not participate in the second study because of a steady decline in general condition. The median age was 60 years (range 42-78). One of the 29 patients had two separate lesions, and MRglc was measured in each separately. The tumor histologic types included squamous cell carcinoma (n = 9), adenocarcinoma (n = 13), large cell carcinoma (n = 6), and poorly differentiated carcinoma (n = 2). The extent of the primary and nodal disease was as follows: Stage IIB (T3N0M0), Pancoast tumor (n = 2); Stage IIIA, T2-T3N2M0 (n = 18); Stage IIIB: T1-T3N3M0 (n = 5) and T4N0M0 (n = 2); a second lesion, T1 (n = 1); and localized stump recurrence (n = 2). A pathologically complete response was obtained in 14 (47%) of the 30 lesions. The remaining 16 lesions had residual cancer. The mean baseline value of the maximal MRglc was 0.333 +/- 0.087 micromol/min/g (n = 16), and it was reduced to 0.0957 +/- 0.059 micromol/min/g 2 weeks after chemoradiotherapy (p = 0.011). The correlation between residual MRglc and pTCP was made using an increment value of 0.02 micromol/min/g between the maximal and minimal values of MRglc. A pathologically complete response was obtained in 6 of 6 patients with residual MRglc of < or = 0.050 micromol/min/g, 3 of 4 with < or = 0.070, 4 of 7 with < or = 0.090, 0 of 4 with < or = 0.110, 1 of 3 with < or = 0.130, and 0 of 6 with > or = 0.130 micromol/min/g. The fitted logistic model showed that residual MRglc corresponding to pTCP 50% and pTCP > or = 95% was 0.076 and < or = 0.040 micromol/min/g, respectively.

CONCLUSION

The correlation between the gradient of residual MRglc after chemoradiotherapy and pTCP is an inverse dose-response relationship. Residual MRglc of 0.076 and < or = 0.040 micromol/min/g, representing pTCP 50% and pTCP > or = 95%, respectively, may be useful surrogate markers for the tumor response to radiotherapy or chemoradiotherapy in lung cancer.

Failure of T stage to predict survival in patients with non-small-cell lung cancer treated by radiotherapy with or without concomitant chemotherapy

PURPOSE

Because T stage does not consistently reflect tumor size in non-small-cell lung cancer (NSCLC), we hypothesized that T stage may be of limited prognostic value in patients with locoregional NSCLC treated by nonsurgical means.

METHODS AND MATERIALS

The study population consisted of 243 patients with histologically or cytologically proven NSCLC treated in three consecutive prospective trials between 1989 and 1998. The eligibility criteria for this analysis included planned for and began treatment at 60 Gy; Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1; weight loss < or = 10%; no prior treatment; and no supraclavicular nodes, pleural effusion, or distant metastases. In the first study, 204 patients were randomized to receive conventional or accelerated radiotherapy (RT) with or without concomitant carboplatin. In the second, 15 patients were treated with concomitant cisplatin, etoposide, and RT in a single-arm study. In the third, 24 patients were treated with concomitant carboplatin, 5-fluorouracil, and RT in a dose-escalation study.

RESULTS

A total of 231 patients for whom the T and N stage were known met the eligibility criteria. The patient characteristics were 77% male, 64% squamous histologic features, 33% ECOG status of 0, and 69% no weight loss. The nodal status was 36% N0, 7% N1, 52% N2, and 5% N3. The estimated median survival for all patients was 1.4 years (95% confidence interval 1.2-1.6), with an estimated 10% surviving 5 years (95% confidence interval 7-15). No significant difference was found in survival among the three trials (p = 0.16). The estimated median survival time and 5-year survival rate according to T stage were as follows: T1 (n = 29), 1.6 years and 16%; T2 (n = 88), 1.3 years and 9%; T3 (n = 59), 1.4 years and 9%; and T4 (n = 55), 1.4 years and 9%. No significant trend was found in overall survival according to T stage (p = 0.85, log-rank). To test whether a significant effect of T stage on overall survival existed after adjusting for N stage, trial, ECOG status, and weight loss, a multifactor analysis using Cox proportional hazards regression analysis was carried out. There was still no significant effect of T stage on survival (p = 0.66) when all factors were taken into account.

CONCLUSION

Although there is some evidence that T stage is an independent prognostic factor in patients with NSCLC treated surgically, it did not appear to be of value in this series of patients treated with RT with and without concomitant chemotherapy.

Lung cancer--where are we today? Current advances in staging and nonsurgical treatment

Lung cancer remains the commonest cause of cancer death in both men and women in the developed world, although mortality rates for men are dropping. Spiral computed tomography (CT) of the chest in middle-aged, smoking subjects may identify two to four times more lung cancers than a chest X-ray, with more than 70% of tumors being Stage I. The incidence of benign nodules is high, making interpretation difficult. Randomized controlled trials are required to determine whether spiral CT detects lung cancer early enough to improve mortality. Preoperative staging has relied on CT scans, but positron emission tomography scanning has greater sensitivity, specificity, and accuracy than CT and is recommended as the final confirmatory investigation when the CT shows resectable disease. In locally advanced non-small cell lung cancer, there is a small advantage for the addition of chemotherapy to radiotherapy, but no advantage for postoperative radiotherapy. Chemotherapy gives no benefit when given as neoadjuvant or adjuvant treatment around surgery. In advanced disease, newer cytotoxic agents confer a small survival advantage over older combinations, but the advantage in median survival over best supportive care remains a few months with modest improvements in quality of life. Survival with small cell lung cancer has shown little increase over the last 15 years despite multiple attempts to manipulate the timing, dose intensity of chemotherapy, and the potential of radiotherapy. Novel therapies are urgently needed for all cell types of lung cancer.

Role of (99m)tc-hexakis-2-methoxy-isobutylisonitrile in the diagnosis and staging of lung cancer

BACKGROUND

Preliminary studies have shown that (99m)Tc-hexakis-2-methoxyisobutylisonitrile (MIBI) is an interesting tracer for various tumors. The aim of this study was to determine the feasibility of using (99m)Tc-MIBI as a diagnostic and staging procedure for lung cancer.

METHODS

We prospectively compared the results of biopsy with (99m)Tc-MIBI imaging in patients with potentially resectable lung lesions (stages IIIA or lower). In the patients with radiopharmaceutical uptake, the staging provided by CT was compared with that obtained with (99m)Tc-MIBI.

RESULTS

Ninety-nine of the 116 patients examined had lung cancer. For the diagnosis of malignancy, the specificity of (99m)Tc-MIBI was 100%, sensitivity was 89.8%, positive predictive value was 100%, negative predictive value was 62.9%, and accuracy was 91.4%. In the 87 patients with radiopharmaceutical uptake in their lung cancer, the values for the specificity and sensitivity of (99m)Tc-MIBI in the detection of mediastinal lymph node metastases were 100% and 54.5%, respectively. The corresponding values for CT in the same patients were 87.6% and 63.3%, respectively. The difference in specificity is statistically significant (p = 0.011).

CONCLUSIONS

This study demonstrates that (99m)Tc-MIBI provides significant diagnostic and staging information in patients with lung lesions. The high specificity and positive predictive value of (99m)Tc-MIBI suggest that this radiopharmaceutical could be a very useful tool for the diagnosis of lung cancer, especially in consideration of its low costs and wide availability.

Positron emission tomography in lung cancer

Carcinoma of the lung is one of the most frequent malignancies and a major cause of mortality. The use of positron emission tomography (PET) has been extensively investigated in patients with carcinoma of the lung and has established clinical utility and cost-effectiveness in characterization of solitary pulmonary nodules and preoperative staging of carcinoma of the lung. Evolving applications in carcinoma of the lung include detection of recurrence, assessment of treatment response, radiotherapy planning, and prognosis. In addition, there is developing interest in combined anatomic/metabolic imaging and new tracer techniques, in particular gene expression imaging. This review aims to present existing data supporting the use of PET in carcinoma of the lung and to explore the evolving indications and future prospects of PET and lung cancer.

The impact of fluorodeoxyglucose F 18 positron-emission tomography on the surgical staging of non-small cell lung cancer

OBJECTIVES

Staging data on patients with non-small cell lung cancer were prospectively collected to evaluate the accuracy and anatomic information provided by fluorodeoxyglucose F 18 positron-emission tomography and its impact on improving the accuracy of surgical staging.

METHODS

A total of 142 patients with potentially resectable non-small cell lung cancer were imaged with positron-emission tomography (neck to pelvis). Positron-emission tomographic scans were read prospectively with thoracic computed tomographic comparison. Patients without distant metastases at positron-emission tomography underwent staging with bronchoscopy and mediastinoscopy, with or without mediastinotomy or thoracoscopy. Patients with metastases, pleural implants, or N2 or N3 disease did not undergo primary resection.

RESULTS

Positron-emission tomography revealed unsuspected distant metastases in 24 of 142 patients (16.9%) and unsuspected pleural implants in 6 others. Nodal stage was surgically established in 118 cases. Positron-emission tomography showed that 5 patients had nodal disease not accessible by mediastinoscopy. In 35 (24.6%) of these 142 cases, positron-emission tomography directed the evaluation away from routine bronchoscopy and mediastinoscopy staging that would have resulted in inappropriate treatment selection. Positron-emission tomography correctly differentiated resectable stages IA through IIIA (N1) from stages IIIA (N2) through IV in 88.7% of cases. In identifying N2 or N3 disease, positron-emission tomography had an accuracy of 90.7%, a sensitivity of 80.9%, a specificity of 96%, and positive and negative predictive values of 91.9% and 90.1%, respectively. Of the 8 cases in which positron-emission tomography missed N2 disease, 7 had the disease discovered by mediastinoscopy and 1 had it discovered at thoracotomy.

CONCLUSIONS

The diagnostic accuracy of positron-emission tomography-enhanced clinical staging is high. Positron-emission tomography has previously been used primarily to screen for lymph node spread and distant metastases, but it also provides localizing information that allows directed and more sensitive surgical staging and refinement of patient selection for curative resection. Positron-emission tomography and surgical staging play complementary roles in the journey toward more accurate overall staging.

Positron emission tomography (PET) and combined imaging modalities for staging lung cancer

FDG PET in its current form supplements but does not yet replace other noninvasive imaging modalities for the evaluation and staging of the patient with NSCLC. Clinicians await further data from well-designed clinical trials to help integrate FDG PET into current clinical practice. Looking forward, sophisticated radiolabeling techniques promise to improve both the diagnostic accuracy of PET and our ability to deliver targeted cancer therapy to patients.

Decision-tree sensitivity analysis for cost-effectiveness of whole-body FDG PET in the management of patients with non-small-cell lung carcinoma in Japan

BACKGROUND

Whole-body 2-fluoro-2-D-[18F]deoxyglucose [FDG] positron emission tomography (WB-PET) may be more cost-effective than chest PET because WB-PET does not require conventional imaging (CI) for extrathoracic staging.

METHODS

The cost-effectiveness of WB-PET for the management of Japanese patients with non-small-cell lung carcinoma (NSCLC) was assessed. Decision-tree sensitivity analysis was designed, based on the two competing strategies of WB-PET vs. CI. WB-PET was assumed to have a sensitivity and specificity for detecting metastases, of 90% to 100% and CI of 80% to 90%. The prevalences of M1 disease were 34% and 20%. One thousand patients suspected of having NSCLC were simulated in each strategy. We surveyed the relevant literature for the choice of variables. Expected cost saving (CS) and expected life expectancy (LE) for NSCLC patients were calculated.

RESULTS

The WB-PET strategy yielded an expected CS of $951 US to $1,493US per patient and an expected LE of minus 0.0246 years to minus 0.0136 years per patient for the 71.4% NSCLC and 34% M1 disease prevalence at our hospital. PET avoided unnecessary bronchoscopies and thoracotomies for incurable and benign diseases. Overall, the CS for each patient was $833US to $2,010US at NSCLC prevalences ranging from 10% to 90%. The LE of the WB-PET strategy was similar to that of the CI strategy. The CS and LE minimally varied in the two situations of 34% and 20% M1 disease prevalence.

CONCLUSIONS

The introduction of a WB-PET strategy in place of CI for managing NSCLC patients is potentially cost-effective in Japan.

[A proposal for the rational use of the PET in oncology]

OBJECTIVE

This study aims to develop a Clinical Practice Guide for the rational use of the Positron Emission Tomography (PET) in Oncology, that makes it possible to approach the real existence of demand in the public health care service of Andalucía, by limiting the clinical indications, using criteria based on the existence of sufficient scientific evidence on the effectiveness and clinical impact of PET.

METHOD

The consensus technique was used to elaborate the Guide, gathering a group of nuclear medicine experts. Prior to this a systematic research of the scientific literature was carried out, using strict criteria for the selection of the articles, such as the evaluation of the epidemiological data, work methodology, clinical and pathological diagnosis, gold standard references and statistical analysis. In each pathology group, the existence of alternative non-invasive diagnostic techniques was assessed, comparing its effectiveness and clinical impact with the PET, and the existence of useful treatments correlated with the results of the examination was also evaluated. When it was possible, we evaluated the cost-effectiveness of the PET. Finally, the cost-effectivity of the technique was assessed and the limitation of present and future resources and the economical costs arising from the PET costs and introduction were evaluated.

RESULTS AND CONCLUSIONS

It was considered that the PET was indicated in the following clinical conditions: 1: Assessment of Colorectal Cancer recurrence in patients with increased levels of tumor markers and negative morphological imaging techniques. Suspicion of isolated resectable recurrence. 2: Restaging in patients with high risk melanoma. 3: Differential diagnosis of solitary pulmonary nodules. 4: Staging of non-small cell bronchial carcinoma. 5: Staging and detection of recurrences of lymphomas. 6: Restaging of head and neck cancer with possibilities of curative treatment. 7: Diagnosis of recurrences in differentiated thyroid cancer in patients with increased plasma levels of thyroglobulin and negative radioiodine scintiscan. 8: Staging and follow-up of medullary thyroid carcinoma. 9: Differential diagnosis between recurrent tumor and scar or radionecrosis in brain tumors.

Positron emission tomography scanning: current and future applications

Whole-body positron emission tomography (PET) imaging with (18)F deoxyglucose (FDG) is a molecular imaging modality that detects metabolic alterations in tumor cells that are common to neoplastic cells. FDG-PET has recently been approved by the Health Care Finance Administration for Medicare reimbursement for diagnosing, staging, and restaging lung cancer, colorectal cancer, lymphoma, melanoma, head and neck cancer, and esophageal cancer. This review discusses the scientific evidence that led to the emergence of PET imaging as an accepted clinical tool in patients with solitary pulmonary nodules, lung cancer, colorectal cancer, melanoma, lymphoma, breast cancer, and other cancers. When possible, we compare the performance of PET to that of anatomical imaging. We discuss future clinical applications of this imaging modality.

Effectiveness of positron emission tomography in the preoperative assessment of patients with suspected non-small-cell lung cancer: the PLUS multicentre randomised trial

BACKGROUND

Up to 50% of curative surgery for suspected non-small-cell lung cancer is unsuccessful. Accuracy of positron emission tomography (PET) with 18-fluorodeoxyglucose (18FDG) is thought to be better than conventional staging for diagnosis of this malignancy. Up to now however, there has been no evidence that PET leads to improved management of patients in routine clinical practice. We did a randomised controlled trial in patients with suspected non-small-cell lung cancer, who were scheduled for surgery after conventional workup, to test whether PET with 18FDG reduces number of futile thoracotomies.

METHODS

Before surgery (mediastinoscopy or thoracotomy), 188 patients from nine hospitals were randomly assigned to either conventional workup (CWU) or conventional workup and PET (CWU+PET). Patients were followed up for 1 year. Thoracotomy was regarded as futile if the patient had benign disease, explorative thoracotomy, pathological stage IIIA-N2/IIIB, or postoperative relapse or death within 12 months of randomisation. The primary outcome measure was futile thoracotomy. Analysis was by intention to treat.

FINDINGS

96 patients were randomly assigned CWU and 92 CWU+PET. Two patients in the CWU+PET group did not undergo PET. 18 patients in the CWU group and 32 in the CWU+PET group did not have thoracotomy. In the CWU group, 39 (41%) patients had a futile thoracotomy, compared with 19 (21%) in the CWU+PET group (relative reduction 51%, 95% CI 32-80%; p=0.003).

INTERPRETATION

Addition of PET to conventional workup prevented unnecessary surgery in one out of five patients with suspected non-small-cell lung cancer.

Advantages of positron emission tomography over computed tomography in mediastinal staging of non-small cell lung cancer

BACKGROUND

New treatment algorithms in early stage non-small cell lung cancer (NSCLC) involving preoperative chemotherapy require accurate clinical staging of the mediastinum. This study compares the accuracy of 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) scanning with that of computed tomography (CT) scanning in the clinical staging of non-small cell lung cancer.

MATERIALS AND METHODS

A retrospective review was performed on 52 patients with NSCLC who were evaluated with both CT and PET scans. All patients had their mediastinal lymph nodes sampled by mediastinoscopy or at the time of thoracotomy for pulmonary resection. Each imaging study was evaluated separately and correlated with histopathologic results.

RESULTS

For detecting mediastinal metastases the sensitivities of PET and CT scans were 67 and 50%, respectively; specificities were 91 and 65%, respectively; accuracies were 88 and 63%, respectively; positive predictive values were 50 and 16%, respectively; negative predictive values were 95 and 88%, respectively. PET scans were significantly better than CT scans at detecting mediastinal metastases (PET, 4/8; CT, 3/19) (P = 0.01).

CONCLUSIONS

PET scanning is superior to CT scanning for clinical staging of the mediastinum in NSCLC. A more confident decision regarding stratification of patients into current treatment algorithms can be made when the decision is based on PET scanning rather than the current "gold standard" of CT scanning.

Tumor localization and image registration of F-18 FDG coincidence detection scans with computed tomographic scans

PURPOSE

The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management.

METHODS

F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated.

RESULTS

All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm +/- 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%.

CONCLUSIONS

Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.

FDG-PET imaging in the management of non-small-cell lung cancer

Lung cancer is currently the leading cause of cancer-related death in both men and women in most Western countries. Tumour stage is the strongest prognostic factor and the most important parameter guiding treatment decision making. Metabolic positron emission tomography imaging with fluorodeoxyglucose (FDG-PET) has consistently proved superior to conventional imaging for staging of non-small-cell lung cancer and provides information of greater prognostic significance than can be obtained using conventional approaches. FDG-PET has been approved in the USA, Germany and the UK as a basic and invaluable tool in the management of lung cancer.

Building a better therapy for stage IIIA non-small cell lung cancer

What do clinicians know about stage IIIA lung cancer? They know accurate staging is critical and requires wide application of mediastinoscopy. They know that surgery and radiation alone each can cure a small subset of patients, and complete resection is of the utmost importance in surgically treated patients. They know that chemotherapy can increase the number of patients cured when combined with definitive radiation, and concurrent chemoradiotherapy seems superior to sequential. Neoadjuvant chemotherapy also seems to cure more patients than surgery alone, but more data are necessary. Trimodality therapy remains a promising but unproved approach in patients with stage IIIA disease. With the exciting new molecularly targeted agents, trials examining quad-modality therapy are just around the corner.

Imaging techniques for diagnosis and staging of lung cancer

Noninvasive imaging modalities continue to offer opportunities in the diagnosis and staging of lung cancer. Positron emission tomography with fluorodeoxyglucose imaging in lung cancer represents an important, new, and accurate tool in the armamentarium of the radiologist. Computed tomography scanning, MR imaging, and PET play a significant role in the selection of patients for curative lung cancer surgery, decreasing the number of unnecessary thoracotomies. The imaging modalities also help to direct the choice of appropriate invasive and surgical procedures.

Value of positron emission tomography for lung cancer staging

OBJECTIVE

The therapeutic strategy in non-small-cell lung cancer (NSCLC) requires exact staging of tumour invasion (T) as well as differentiation between ipsi- and contralateral lymph node invasion (N1/2 vs N3). [18F]FDG-positron emission tomography (FDG-PET) has been shown to detect invaded N with high accuracy while correct determination of T appears to be unclear. The purpose of this prospective study was to evaluate benefit and necessity of 18FDG-PET as an additive to conventional staging modalities.

METHODS

Forty patients with suspected non-small-cell lung cancer (NSCLC) were staged by means of computed tomography (CT), bronchoscopy, mediastinoscopy and bone scintigraphy. Additionally, attenuation corrected FDG-PET of the thorax was performed pre-operatively for analysis of T and N topography. After surgical resection with radical lymphadenectomy T and N staging results of CT and PET were compared with the pathological diagnoses. Specificity, sensitivity, positive predictive value and accuracy of CT and PET were calculated.

RESULTS

Twenty three squamous cell carcinomas, 14 adenocarcinomas, and three non-malignant tumours were found. Accuracy of CT-T was 0.75 and of PET-T 0.78; accuracy of CT-N was 0.78 and of PET-N 0.80. By combination of CT-T and PET-T accuracy was 0.88. Combination of CT-N and PET-N yielded an accuracy of 0.90. In two out of three cases, PET correctly determined T0. In two cases non-malignant inflammatory lymph nodes were falsely staged as malignant by PET.

CONCLUSIONS

Adequate pre-operative T- and N-staging is possible with both CT and FDG-PET. Accuracy can be improved by combination of CT and FDG-PET. FDG-PET is superior to CT in order to differentiate between malignant and benign tumours. However, acute inflammation can mimic malignant lymph node invasion. FDG-PET is justified as a supporting staging measure in cases presenting unclear differentiation between N2 and N3 after conventional staging and is helpful in cases with unclear cell type of the primary tumour.

The impact of (18)FDG-PET on target and critical organs in CT-based treatment planning of patients with poorly defined non-small-cell lung carcinoma: a prospective study

PURPOSE

To prospectively study the impact of coregistering (18)F-fluoro-deoxy-2-glucose hybrid positron emission tomographic (FDG-PET) images with CT images on the planning target volume (PTV), target coverage, and critical organ dose in radiation therapy planning of non-small-cell lung carcinoma.

METHODS AND MATERIALS

Thirty patients with poorly defined tumors on CT, referred for radical radiation therapy, underwent both FDG-PET and CT simulation procedures on the same day, in radiation treatment position. Image sets were coregistered using external fiducial markers. Three radiation oncologists independently defined the gross tumor volumes, using first CT data alone and then coregistered CT and FDG-PET data. Standard margins were applied to each gross tumor volume to generate a PTV, and standardized treatment plans were designed and calculated for each PTV. Dose-volume histograms were used to evaluate the relative effect of FDG information on target coverage and on normal tissue dose.

RESULTS

In 7 of 30 (23%) cases, FDG-PET information changed management strategy from radical to palliative. In 5 of the remaining 23 (22%) cases, new FDG-avid nodes were found within 5 cm of the primary tumor and were included in the PTV. The PTV defined using coregistered CT and FDG-PET would have been poorly covered by the CT-based treatment plan in 17--29% of cases, depending on the physician, implying a geographic miss had only CT information been available. The effect of FDG-PET on target definition varied with the physician, leading to a reduction in PTV in 24-70% of cases and an increase in 30-76% of cases. The relative change in PTV ranged from 0.40 to 1.86. On average, FDG-PET information led to a reduction in spinal cord dose but not in total lung dose, although large differences in dose to the lung were seen for a few individuals.

CONCLUSION

The coregistration of planning CT and FDG-PET images made significant alterations to patient management and to the PTV. Ultimately, changes to the PTV resulted in changes to the radiation treatment plans for the majority of cases. Where possible, we would recommend that FDG-PET data be integrated into treatment planning of non-small-cell lung carcinoma, particularly for three-dimensional conformal techniques.

Performance of sodium iodide based (18)F-fluorodeoxyglucose positron emission tomography in the characterization of indeterminate pulmonary nodules or masses

The purpose of this study was to document the accuracy of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) with sodium iodide detectors in characterizing indeterminate lung nodules or masses and in identifying additional extra-lesional findings. 50 consecutive patients without a confident diagnosis of malignancy on CT underwent (18)FDG PET with and without attenuation correction. The diagnosis of malignancy was made using visual diagnostic criteria, and tumour-to-blood pool ratios were calculated. The final diagnosis was established by surgery, biopsy or long-term follow-up. Any additional findings made at PET were recorded and similarly verified. Using blinded visual diagnostic criteria for the differentiation of malignant from benign nodules, sodium iodide PET achieved a sensitivity of 91% (30 of 33 cases), a specificity of 88% (15 of 17 cases), a positive predictive value for malignancy of 94% (30 of 32 cases) and a negative predictive value of 83% (15 of 18 cases). False positives occurred with active tuberculosis and sarcoidosis. False negatives were a 3 cm bronchoalveolar carcinoma, a 1.3 cm sarcoma metastasis and a 1 cm carcinoma. Use of tumour-to-blood pool ratios did not improve performance. PET suggested the presence of nodal or distant metastases in 13 of 33 patients with a malignant pulmonary lesion. These PET findings were confirmed in 11 patients. These results indicate that sodium iodide PET is an accurate tool for the characterization of indeterminate pulmonary masses or nodules and simultaneously provides non-invasive staging information that can alter patient management in up to one-third of such patients. Performance of sodium iodide PET is comparable with reported results for PET scanners using other detector materials.

Early mortality after radical radiotherapy for non-small-cell lung cancer: comparison of PET-staged and conventionally staged cohorts treated at a large tertiary referral center

PURPOSE

At our center, approximately 30% of radical radiotherapy (RRT) candidates become ineligible for RRT for non-small-cell lung cancer (NSCLC) after positron emission tomography (PET). We hypothesized that early cancer death rates would be lower in patients receiving RRT after PET staging compared with conventionally staged patients.

METHODS AND MATERIALS

Two prospective cohorts were compared. Cohort 1 consisted of all participants in an Australian randomized trial from our center given 60 Gy conventionally fractionated RRT with or without concurrent carboplatin from 1989 to 1995. Eligible patients had Stage I--III, Eastern Cooperative Oncology Group status 0 or 1, <10% weight loss, and had not undergone PET. Cohort 2 included all RRT candidates between November 1996 and April 1999 who received RRT after PET staging and fulfilled the above criteria for stage, Eastern Cooperative Oncology Group status, and weight loss.

RESULTS

Eighty and 77 eligible patients comprised the PET and non-PET groups, respectively. The PET-selected patients had significantly less weight loss; 73% and 49% of the PET and non-PET patients, respectively, received chemotherapy. The median survival was 31 months for PET patients and 16 months for non-PET patients. Mortality from NSCLC and other causes in the first year was 17% and 8% for PET patients and 32% and 4% for non-PET patients, respectively. The hazard ratio for NSCLC mortality for PET vs. non-PET patients was 0.49 (p = 0.0016) on unifactorial analysis and was 0.55 (p = 0.0075) after adjusting for chemotherapy, which significantly improved survival.

CONCLUSION

Patients selected for RRT after PET have lower early cancer mortality than those selected using conventional imaging.

Outcomes and cost-effectiveness of alternative staging strategies for non-small-cell lung cancer

PURPOSE

To identify the optimal strategy for staging the mediastinum of patients with known non-small-cell lung cancer (NSCLC), stratified by tumor (T) classification.

METHODS

We used a decision-analytic model to compare the health outcomes and cost-effectiveness of three staging strategies: (1) chest computed tomography alone, (2) selective mediastinoscopy, and (3) routine mediastinoscopy. The overall effectiveness and cost of each strategy was a function of the proportion of patients accurately staged and the risks, benefits, and costs of the diagnostic tests and treatments used. Probability estimates and costs were derived from primary data and the literature. We adopted a societal perspective and calculated incremental cost-effectiveness ratios (ICERs) as cost per quality-adjusted life year (QALY) gained.

RESULTS

Both mediastinoscopy strategies correctly identified more patients with mediastinal involvement (N2/N3 disease) and assigned them to multimodal regimens. Routine mediastinoscopy maximized quality-adjusted life expectancy in all patients, irrespective of T classification, and this result was robust to varying the model estimates over their reported ranges. In T1 patients, selective mediastinoscopy cost $24,500 per QALY gained, compared with $78,800 per QALY gained for routine mediastinoscopy. In T2 and T3 patients, the ICER of routine mediastinoscopy was more favorable ($42,800 and $53,400 per QALY gained, respectively).

CONCLUSION

Routine mediastinoscopy maximizes quality-adjusted life expectancy in patients with known NSCLC, and its ICER compares favorably with other currently accepted medical technologies. The survival benefit and cost-effectiveness of this strategy are greater in patients with T2 and T3 tumors and are likely to improve with advances in multimodal therapy.

An initial experience with FDG-PET in the imaging of residual disease after induction therapy for lung cancer

BACKGROUND

The 2-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) imaging is an advance over computed tomography alone in the staging of untreated nonsmall cell lung cancer (NSCLC). Aside from one 9-patient study, there are no data comparing FDG-PET imaging with surgical staging of NSCLC after induction therapy.

METHODS

We reviewed our institutional experience with FDG-PET imaging followed by surgical staging of nonsmall cell lung cancer after induction therapy. A nuclear physician blinded to surgical findings reviewed the FDG-PET scans and assigned a clinical TNM stage. A thoracic surgeon assigned a pathologic TNM stage. Then the clinical TNM stage and the pathologic TNM stage were compared.

RESULTS

Fifty-six patients (30 males and 26 females; median, age 60) with nonsmall cell lung cancer underwent chemotherapy (40 patients), chemoradiation (11 patients), or radiation alone (5 patients) followed by PET and operations. PET had a positive predictive value of 98% for detecting residual viable disease in the primary tumor. PET over-staged nodal status in 33% of patients, under staged nodal status in 15%, and was correct in 52%. PET correctly classified all patients with M1 disease.

CONCLUSIONS

Positron emission tomography after induction therapy accurately detects residual viable primary tumor, but not the involvement of mediastinal lymph nodes.

Practice, efficacy and cost of staging suspected non-small cell lung cancer: a retrospective study in two Dutch hospitals

BACKGROUND

A study was undertaken to investigate the clinical practice, yield, and costs of preoperative staging in patients with suspected NSCLC and to obtain baseline data for prospective studies on the cost effectiveness of (18)F-fluorodeoxyglucose positron emission tomography in the management of these patients.

METHODS

A retrospective study of the medical records of all patients with suspected NSCLC was performed during a 2 year interval (1993-4) in an academic and a large community hospital.

RESULTS

Three hundred and ninety five patients with suspected NSCLC were identified; 58 were deemed to be medically inoperable and 337 patients proceeded to the staging process. Staging required a mean (SD) of 5.1 (1.5) diagnostic tests per patient (excluding thoracotomy) carried out over a median period of 20 days (IQR 10-31). Many of the tests (including both invasive and non-invasive) were done because previous imaging tests had suggested metastases, and in most cases the results of initial tests proved to be false positives. After clinical staging, 168 patients were considered to be resectable (stage I/II) and 144 patients underwent surgery with curative intent. At surgery 33 patients (23% of those who underwent surgery) were found to have irresectable lesions and 19 (13%) had a benign lesion. Surgery was also considered to be futile in 22 patients (15%) who developed metastases or local recurrence within 12 months following radical surgery. Hospital admission was responsible for most of the costs.

CONCLUSION

In many patients staging involved considerable effort in terms of the number of diagnostic tests, the duration of the staging period and the cost, with limited success in preventing futile surgery. Failures relate to the quality of diagnostic preparation at every level of the TNM staging system.

Whole-body FDG-PET imaging in the management of patients with cancer

Fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging is increasingly used for the management of patients with cancer. The technique is now well accepted by most physicians as an effective complement to the existing imaging modalities. For many malignancies, PET achieves high sensitivity and specificity. The critical role of this powerful technique is realized increasingly in the day-to-day practice of oncology. This is particularly true for the management of patients with non-small-cell lung cancer (NSCLC). The contribution of PET for the selection of patients eligible for curative treatments in this setting is well established. Convincing data also exist to support the use of PET for evaluating patients with recurrent colorectal carcinoma, for staging and restaging lymphomas, and for diagnosing recurrent thyroid carcinoma in the presence of elevated thyroglobulin and negative 131I scans. Other indications include staging of various recurrent malignancies, such as breast cancer, melanoma, and head and neck and gynecologic carcinomas. Existing data are limited for the determination of the impact of PET in certain malignancies, and further studies, which should include outcome information, will allow clarification of the role of this modality for such indications. Despite the small number of studies specifically designed to assess changes in management plans for some malignancies after performing PET the overall favorable results are encouraging enough at this time to include this modality as an essential element of the practice of modern oncology. Finally, the evolving role of PET imaging as a predictor of response after local or systemic treatment may add a major dimension to the application of this novel technique.

Curative radiotherapy for a second primary lung cancer arising after pneumonectomy -- techniques and results

BACKGROUND AND PURPOSE

Only limited data exist on the outcome of curative radiotherapy in patients who develop a second primary lung tumour after pneumonectomy. The treatment of eight such patients is described.

MATERIALS AND METHODS

The case records of patients who underwent curative radiotherapy for stage I non-small cell lung cancer after a previous pneumonectomy were reviewed. Treatment was delivered using 3D external radiotherapy to a dose of 50-70 Gy, in once-daily fractions of 2-2.5 Gy. An endobronchial brachytherapy boost was used in three patients. Original treatments were re-planned in an attempt to minimize the volume of irradiated lung.

RESULTS

A complete remission was achieved in five (of six) evaluable patients, but two patients subsequently developed a local relapse. All patients survived for a minimum of 1 year after treatment. Only one patient developed significant (grade 2) radiation pneumonitis. When treatments were re-planned to optimize beam arrangements, and when customized blocks were used, the mean lung volume receiving > or = 20 Gy (calculated for 70 Gy) decreased from 24.6+/-4.1 (range, 18-31%) to 17.3+/-5.1% (range, 12-26%). Similarly, the radiation conformity index improved from 0.44+/-0.11 to 0.61+/-0.06.

CONCLUSIONS

Involved-field radiotherapy can be curative in patients who develop a new lung tumour after pneumonectomy. Recent advances in defining target volumes, treatment planning and delivery are likely to improve upon these results.

Surgery for non-small cell lung cancer--new trends

New trends in lung cancer surgery focus on new approaches to the management of the primary tumour, combined modality approaches to both local and distant control of the tumour, new approaches to ensure resectability by staging and techniques to expand the limits of operability. With new screening methods for NSCLC there is a trend toward sublobar, segmental resections of smaller tumours including an expanding use of video assisted thoracoscopy. Improvements in surgical and anaesthetic procedures have stimulated a renewed interest in the resection of locally advanced tumours. The understanding that local control alone may not give the best chance of long term survival has stimulated new trends in the use of neoadjuvant and adjuvant chemotherapy. There is a trend towards more detailed preoperative and intraoperative nodal staging in NSCLC, including video assisted techniques, and the identification of sentinel lymph node involvement to direct lymph node dissection. Increased understanding of the physiological benefits of surgery in emphysema have resulted in a re-evaluation of the selection of patients for lung cancer surgery. This together with a greater application of bronchoplastic and angioplastic techniques is leading to greater resection rates.

Staging of non-small cell lung cancer: consensus, controversies and challenges

Stage is with performance status, the most potent prognostic factor in non-small cell lung cancer. In the past decades, much effort has been directed towards the definition, description, development and implementation of staging guidelines. This has undoubtedly resulted in improvements in therapy and insight in the biology of the disease. The new millennium sees us confronted with an increasing epidemic of lung cancer. Hence, the need for further improvements in staging accuracy and cost effectiveness, in order to use the available therapeutic armament at its best and provide the patient with a treatment that is best adjusted to his or her condition. Current controversies and future challenges in staging will be addressed.

Positron emission tomography (PET) of non-small cell lung cancer

Positron emission tomography (PET) with FDG has shown to be of substantial value in differential diagnosis of pulmonary lesions and in the assessment of lymph node involvement with higher sensitivity and specificity than CT. A negative PET scan of the mediastinum suggests that mediastinoscopy is unnecessary and that these patients can proceed directly to thoracotomy. The method is also useful for the visualization of distant metastases. Since changes of treatment may result after identification of distant metastases PET is also cost-effective [Eur J Nucl Med 27(2000)1598; Australas Radiol 45(2001)9]. Furthermore, changes of tumor metabolism can be detected with PET at early stages after treatment, which can be used for therapy monitoring and for the detection of recurrent tumor tissue after completion of treatment.

Imaging of lung cancer with CT, MRT and PET

The staging of non-small lung cancer has to be performed in an interdisciplinary approach considering all clinical, radiological and histologic results. The staging using imaging procedures is done according to the TNM classification with T describing the extent of the primary tumor, N the presence and location of metastatic lymph nodes and M the presence or absence of distant metastases. It is important to remember that the individual stages of the TNM classification have undergone numerous revisions and thus need to be considered in their most recent version [Chest 111 (1997) 1718; Chest 111 (1997) 1710]. Noninvasive information about the stage of the disease is important for the planning and optimization of therapy. This may be done with imaging procedures such as, CT, MRT or PET.