Computed tomography of the brain, chest, and abdomen in the preoperative assessment of non-small cell lung cancer

Impact of neuroimaging in the pretreatment evaluation of early stage non-small cell lung cancer

Background

There are limited data and conflicting guideline recommendations regarding the role of neuroimaging in the pretreatment evaluation of non-small cell lung cancer (NSCLC).

Methods

We performed a retrospective, pragmatic cohort study of patients with NSCLC diagnosed between January 1 and December 31, 2015. Eligible patients were identified from an institutional tumor registry. We collected all records of pretreatment neuroimaging within 12 weeks of diagnosis, including CT head (CT) and MRI brain (MRI). We abstracted the indication for neuroimaging, presence of central neurologic symptoms and cancer stage (with and without neuroimaging findings) from the tumor registry and the electronic health record.

Results

We identified 216 evaluable patients with newly diagnosed NSCLC. 157 of 216 patients (72.7%) underwent neuroimaging as part of initial staging, and 41 (26%) were found to have brain metastases. Of 43 patients with central neurologic symptoms at the time of neuroimaging, 28 (67%) had brain metastasis. In patients without central neurologic symptoms, brain metastases were discovered in 0 of 33 patients with clinical stage I or II, 4 of 36 (11%) with clinical stage III and 9 of 45 (20%) with clinical stage IV disease.

Conclusions

In patients with early stage NSCLC (i.e. clinical stage I and II) without central neurologic symptoms, brain metastases are unlikely. The continued use of neuroimaging in the pretreatment evaluation of clinical stage I patients without central neurologic symptoms is not needed.

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

BACKGROUND

Correctly staging lung cancer is important because the treatment options and prognosis differ significantly by stage. Several noninvasive imaging studies and invasive tests are available. Understanding the accuracy, advantages, and disadvantages of the available methods for staging non-small cell lung cancer is critical to decision-making.

METHODS

Test accuracies for the available staging studies were updated from the second iteration of the American College of Chest Physicians Lung Cancer Guidelines. Systematic searches of the MEDLINE database were performed up to June 2012 with the inclusion of selected meta-analyses, practice guidelines, and reviews. Study designs and results are summarized in evidence tables.

RESULTS

The sensitivity and specificity of CT scanning for identifying mediastinal lymph node metastasis were approximately 55% and 81%, respectively, confirming that CT scanning has limited ability either to rule in or exclude mediastinal metastasis. For PET scanning, estimates of sensitivity and specificity for identifying mediastinal metastasis were approximately 77% and 86%, respectively. These findings demonstrate that PET scanning is more accurate than CT scanning, but tissue biopsy is still required to confirm PET scan findings. The needle techniques endobronchial ultrasound-needle aspiration, endoscopic ultrasound-needle aspiration, and combined endobronchial ultrasound/endoscopic ultrasound-needle aspiration have sensitivities of approximately 89%, 89%, and 91%, respectively. In direct comparison with surgical staging, needle techniques have emerged as the best first diagnostic tools to obtain tissue. Based on randomized controlled trials, PET or PET-CT scanning is recommended for staging and to detect unsuspected metastatic disease and avoid noncurative resections.

CONCLUSIONS

Since the last iteration of the staging guidelines, PET scanning has assumed a more prominent role both in its use prior to surgery and when evaluating for metastatic disease. Minimally invasive needle techniques to stage the mediastinum have become increasingly accepted and are the tests of first choice to confirm mediastinal disease in accessible lymph node stations. If negative, these needle techniques should be followed by surgical biopsy. All abnormal scans should be confirmed by tissue biopsy (by whatever method is available) to ensure accurate staging. Evidence suggests that more complete staging improves patient outcomes.

Clinical and organizational factors in the initial evaluation of patients with lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines

BACKGROUND

This guideline is intended to provide an evidence-based approach to the initial evaluation of patients with known or suspected lung cancer. It also includes an assessment of the impact of timeliness of care and multidisciplinary teams on outcome.

METHODS

The applicable current medical literature was identified by a computerized search and evaluated using standardized methods. Recommendations were framed using the approach described by the Guidelines Oversight Committee of the American College of Chest Physicians. Data sources included MEDLINE and the Cochrane Database of Systematic Reviews.

RESULTS

Initial evaluation should include a thorough history and physical examination; CT imaging; pulmonary function tests; and hemoglobin, electrolyte, liver function, and calcium levels. Additional testing for distant metastases and paraneoplastic syndromes should be determined on the basis of these results. Paraneoplastic syndromes may have an adverse impact on cancer treatment, so they should be controlled rapidly with the goal of proceeding with definitive cancer treatment in a timely manner. Although the relationship between timeliness of care and survival is difficult to quantify, efforts to deliver timely care are reasonable and should be balanced with the need to attend to other dimensions of health-care quality (eg, safety, effectiveness, efficiency, equality, consistency with patient values and preferences). Quality care will require multiple disciplines. Although it is difficult to assess the impact, we suggest that a multidisciplinary team approach to care be used, particularly for patients requiring multimodality therapy.

CONCLUSIONS

The initial evaluation of patients with lung cancer should include a thorough history and physical examination, pulmonary function tests, CT imaging, basic laboratory tests, and selective testing for distant metastases and paraneoplastic syndromes.

Immunohistochemical markers associated with brain metastases in patients with nonsmall cell lung carcinoma

BACKGROUND

To the authors' knowledge, there are no reliable markers able to identify patients with nonsmall cell lung cancer (NSCLC) that will develop metastases to the brain. The authors investigated associations between immunohistochemical markers and the development of brain metastases in patients with NSCLC.

METHODS

This was a hospital-based, case-control study of patients who were newly diagnosed with NSCLC between 1989 and 2003, developed brain metastases, and had pathology material available from both the primary NSCLC and the brain metastases. These patients were compared with a control group of patients who had NSCLC and no evidence of brain metastases. NSCLC was examined for expression levels of Ki-67, caspase-3, vascular endothelial growth factor A (VEGF-A), VEGF-C, E-cadherin, and epidermal growth factor receptor (EGFR) in 54 surgical pathology specimens using immunohistochemistry, and associations were evaluated between those markers and the development of brain metastases.

RESULTS

Brain metastases developed after a median of 12.5 months (range, 1.7-89.4 months) after the diagnosis of NSCLC. A significantly increased risk of developing brain metastases was associated with patients with NSCLC who had primary tumors with high Ki-67 levels (adjusted odds ratio [OR] of 12.2; 95% confidence interval [95% CI], 2.4-70.4 [P < .001]), low caspase-3 expression (adjusted OR of 43; 95% CI, 5.3 to >100 [P < .001]), high VEGF-C expression (adjusted OR of 14.6; 95% CI, 2.0 to >100 [P < .001]), and low E-cadherin (adjusted OR of 3.6; 95% CI, 0.9-16.4 [P = .05]). No significant risk was associated with VEGF-A or EGFR expression. High Ki-67 expression also was associated with a shorter overall survival (P = .04).

CONCLUSIONS

The results of the current study indicated that patients with NSCLC who had high Ki-67 expression, low caspase-3 expression, high VEGF-C expression, and low E-cadherin expression in their tumors may benefit from close surveillance because they may have an increased risk of developing brain metastases.

Noninvasive staging of non-small cell lung cancer: ACCP evidenced-based clinical practice guidelines (2nd edition)

BACKGROUND

Correctly staging lung cancer is important because the treatment options and the prognosis differ significantly by stage. Several noninvasive imaging studies including chest CT scanning and positron emission tomography (PET) scanning are available. Understanding the test characteristics of these noninvasive staging studies is critical to decision making.

METHODS

Test characteristics for the noninvasive staging studies were updated from the first iteration of the lung cancer guidelines using systematic searches of the MEDLINE, HealthStar, and Cochrane Library databases up to May 2006, including selected metaanalyses, practice guidelines, and reviews. Study designs and results are summarized in evidence tables.

RESULTS

The pooled sensitivity and specificity of CT scanning for identifying mediastinal lymph node metastasis were 51% (95% confidence interval [CI], 47 to 54%) and 85% (95% CI, 84 to 88%), respectively, confirming that CT scanning has limited ability either to rule in or exclude mediastinal metastasis. For PET scanning, the pooled estimates of sensitivity and specificity for identifying mediastinal metastasis were 74% (95% CI, 69 to 79%) and 85% (95% CI, 82 to 88%), respectively. These findings demonstrate that PET scanning is more accurate than CT scanning. If the clinical evaluation in search of metastatic disease is negative, the likelihood of finding metastasis is low.

CONCLUSIONS

CT scanning of the chest is useful in providing anatomic detail, but the accuracy of chest CT scanning in differentiating benign from malignant lymph nodes in the mediastinum is poor. PET scanning has much better sensitivity and specificity than chest CT scanning for staging lung cancer in the mediastinum, and distant metastatic disease can be detected by PET scanning. With either test, abnormal findings must be confirmed by tissue biopsy to ensure accurate staging.

Detecting extrathoracic metastases in patients with non-small cell lung cancer: Is routine scanning necessary?

There is controversy over whether to scan extrathoracic sites for metastases in patients with non-small cell lung cancer (NSCLC). We tested the efficiency of clinical factors to determine whether metastasis has occurred, and whether routine scanning for NSCLC is required. Nine hundred and forty five patients scanned for extrathoracic metasates were included. Clinical factors indicating metastasis were determined using multivariate analysis. Of the 945 cases, 377 (39.9%) had metastasis. Bone metastases were determined by focal skeleton pains, elevated serum alkaline phosphatase levels, adenocarcinoma, KPS</=70, sensitivity of 90.6, specificity of 12.7, PPV of 16.3, NPV of 87.8, and silent metastases rate (SMR) of 9.4%. Brain metastases were determined by neurological symptoms, adenocarcinoma, hematocrite <40 for men and <35 for women, KPS</=70, sensitivity of 89.9, specificity of 7.9, PPV of 9.2, NPV of 88.3, and SMR of 10.1%. Abdominal metastases were determined by abdominal pain/tension, hepatomegaly, elevated GGT levels, serum LDH levels >500 IU, a N2 or N3 case, KPS</=70, sensitivity of 95.9, specificity of 7.1, PPV of 13.3, NPV of 92.1 and SMR of 4.1%. Of the 224 patients with stage I and II disease, 73 had metastasis with a rate of 10.9% silent metastasis. We concluded that routine scanning of NSCLC for staging is necessary.

Does initial staging or tumor histology better identify asymptomatic brain metastases in patients with non-small cell lung cancer?

BACKGROUND

To determine whether the distribution, staging features, or tumor histology of non-small cell lung cancer (NSCLC) distinguishes neurologically symptomatic from asymptomatic patients initially diagnosed with lung cancer, and to determine whether these factors may predict the presence of brain metastasis.

METHODS

We performed a retrospective review of 809 patients with NSCLC and brain metastases who were treated in our institution between January 1996 and March 2003. Patients who had brain metastasis on initial staging were included. Thoracic computed tomographic scans were reviewed for lung tumor features and staging. Neurological computed tomographic or magnetic resonance image scans were assessed for distribution of brain metastases. Medical records were reviewed for comprehensive staging, tumor histology, and neurological symptoms. Fisher's exact test was used to determine any differences among tumor histology, staging, and imaging features among patients with or without neurological symptoms.

RESULTS

Of the 809 patients, 181 had brain metastasis at initial staging. Among these 181 patients, 120 (66%) presented with neurological symptoms (group 1); 61 (34%) patients were asymptomatic (group 2). Patients with adenocarcinoma and large-cell carcinoma had greater odds of brain metastases than patients with squamous cell carcinoma (p = 0.001). There were 106 (58.6%) patients with adenocarcinoma, 32 (17.7%) with large cell carcinoma, and 18 (9.9%) with squamous cell carcinoma. In both groups, most lung cancers were in the right lung with upper lobe dominance. No significant difference in tumor histology or T stage was found between groups, although group 2 was more likely to have a higher N stage. Of the 181 patients with brain metastasis, 60 (33.1%) had N0 disease, 51 (28.2%) had T1 disease, and 23 (19.2%) had no other metastasis. There was no correlation between number/distribution of brain metastases and tumor histology, although patients with disease in the cerebellum or temporal lobes had a greater likelihood of neurological symptoms (odds ratio 3.7).

CONCLUSION

There was no significant difference in tumor histology, staging, or distribution between symptomatic or asymptomatic patients with NSCLC with brain metastases. The odds of brain metastases were greater in those with adenocarcinoma or large-cell carcinoma.

Le bilan préopératoire du cancer bronchique

INTRODUCTION

The overall prognosis of non-small cell carcinoma of the bronchus (NSCLC) remains poor on account of frequently late diagnosis and associated co-morbidity preventing the optimal treatment of the tumour. Surgical resection remains the best curative treatment for limited stage disease.

STATE OF THE ART

The pre-operative assessment should determine whether the extent of the tumour permits complete resection and whether the physiological state of the patient would tolerate the curative resection required. The ultimate goal is to improve 5-year survival. In the case of initial inoperability the assessment should determine whether pre-operative oncological treatment might make an advanced tumour operable (e.g. stage IIIA), or whether targeted medical treatment might improve the patient sufficiently to tolerate an intervention initially judged too risky. The rapid development of the technical modalities available for the assessment requires a continuous review of the current practice guidelines. Positron emission tomography has considerably augmented the accuracy of classical radiological assessment. Nevertheless staging by imaging alone remains imprecise to the extent that invasive examinations are still necessary to provide histological proof of the clinical stage of NSCLC. The techniques for assessing mediastinal invasion are developing rapidly and becoming more accurate and less invasive. Mediastinoscopy enhanced by modern video technology, ultrasound guided endoscopic biopsies and thoracoscopy are complimentary rather than competing techniques. The functional assessment should estimate the operative risk of the proposed pulmonary resection, identify the targeted actions aimed at reducing this risk or, in the absence of such actions, suggest less invasive but less well validated surgical techniques or even palliative treatments. When the operative risk cannot be reduced its precise estimation at least allows the patient to decide whether the risk seems acceptable in relation to the chances of a cure.

VIEWPOINT AND CONCLUSIONS

In the future the pre-operative assessment of NSCLC should improve the detection of micro-metastases in order to optimise the choice of induction and adjuvant therapies. The increasing use of induction chemotherapy before surgical resection can only increase the importance of a detailed assessment for the selection of patients and the evaluation of results.

Role of computed tomography in lung cancer staging

PURPOSE OF REVIEW

Computed tomography has always been an important imaging technique in lung cancer staging but, due to its well-known limitations, additional imaging and/or invasive tests are usually performed. Purpose of this review is to determine whether new developments in CT and in the other staging techniques have changed the role of CT.

RECENT FINDINGS

Despite important technical improvements and the availability of new CT applications, the recent literature confirms the limitations of CT in staging patients with NSCLC. Most attention was given however to other invasive and noninvasive staging techniques and their accuracy in comparison with CT. It was shown that FDG-PET is very useful in the preoperative patient with NSCLC and that it is, especially in N-staging, more accurate than CT. Also combining CT or FDG-PET with EUS-FNA biopsy seems to be a good approach in some indications. Finally, the first reports on the use of integrated PET-CT scanners in lung cancer staging were published and very promising results were shown.

SUMMARY

Computed tomography stays nevertheless the routine imaging procedure for staging patients with NSCLC although performing a PET scan in addition to this CT examination seems to be a good approach that can reduce but certainly not always avoid invasive staging procedures. Mediastinoscopy is still generally considered the standard of care when tissue needs to be obtained from suspicious nodes on FDG-PET and/or CT, although minimally invasive biopsy techniques could replace to a large extent this more invasive technique in the near future.

Current state of imaging for lung cancer staging

Proper selection and interpretation of imaging studies is essential to provide optimal treatment to patients who have lung cancer. The following combines the recommendations of the American College of Chest Physicians [74] and the authors' current clinical practice guidelines: --All patients who have known or suspected lung cancer should undergo a CT of the chest and upper abdomen. --An FDG-PET study should be performed, if available. --Mediastinoscopy should be performed in all patients except those who have peripheral small (<2 cm) tumors and no evidence of N2 disease on CT or PET imaging. --MRI should be performed for tumors of the superior sulcus to define the relationship of the tumor to adjacent neurovascular structures. --Patients who have neurologic signs or symptoms should undergo a brain imaging study (CT or MRI). --Screening for extrathoracic disease is not necessary in asymptomatic patients who have clinical stage I or II disease.

The value of performing head CT in screening for cerebral metastases in patients with potentially resectable non-small cell lung cancer: experience from a UK cardiothoracic centre

AIM

To evaluate the whether screening for cerebral metastases in neurologically intact patients with potentially resectable non-small cell lung cancer patients is both worthwhile and cost-effective.

METHODS

We prospectively performed computed tomography (CT) of the head in 105 consecutive patients with potentially resectable lung cancer over an 18-month period. None of these patients had neurological symptoms or signs.

RESULTS

Five patients (4.8%) with cerebral metastases were identified using CT. At our institution the financial saving of avoiding five thoracotomies was pound sterling 45,000, whilst the cost of performing 105 head CTs was pound sterling 16,000. This represented a substantial saving for the healthcare provider and preserved the quality of life in five patients.

CONCLUSIONS

We conclude that screening for cerebral metastases in neurologically intact patients with potentially resectable non small cell lung cancer patients is both worthwhile and cost effective.

Does Whole-Body 2-[ 18 F]-Fluoro-2-Deoxy-D-Glucose Positron Emission Tomography Have an Advantage Over Thoracic Positron Emission Tomography for Staging Patients With Lung Cancer?

BACKGROUND

Whole-body (WB) positron emission tomography (PET) with 2-[(18)F]-fluoro-2-deoxy-D-glucose (FDG) is more accurate than other imaging studies for detecting lung cancer and extrathoracic metastatic disease. Thoracic PET (from the skull base through the kidneys) may be equally as useful as WB PET (skull base to mid-thigh). With the recent introduction of hybrid CT-PET systems, use of thoracic PET would minimize radiation dose.

METHODS

A retrospective review of a series of WB PET scans performed in our department was performed to identify patients evaluated for a solitary pulmonary nodule or newly diagnosed lung cancer who had distant extracranial and extrathoracic metastases detected by PET. All patients with true extrathoracic metastases were documented by ancillary radiologic and clinical data. Patients were staged according to the American Joint Committee on Cancer TNM system based on findings within the confines of a thoracic PET and WB PET. Comparison was made between staging based on thoracic and WB PET to determine if there was a significant difference.

RESULTS

Of 1,026 studies, distant extracranial metastases were described in 35 patients with lung cancer. Findings were determined to be false-positive in nine patients. Of the 26 patients with true metastases on WB PET, 25 patients had metastatic lesions within the confines of thoracic PET. Relative to WB PET, the sensitivity of thoracic PET is 96.2% (95% confidence interval, 1 to 99.3%) for detection of distant metastases. Only one patient had an isolated metastasis that was detected only by WB PET. This patient would have been staged IIIB by thoracic PET as opposed to stage IV by WB PET.

CONCLUSIONS

Thoracic PET, when compared to WB PET, is 96.2% sensitive for detecting extrathoracic metastases in patients with newly diagnosed non-small cell lung cancer.

Seeking a home for a PET, part 2: Defining the appropriate place for positron emission tomography imaging in the staging of patients with suspected lung cancer

In patients who have a high likelihood of having lung cancer, there is little role for positron emission tomography (PET) imaging for diagnosis of the primary lesion. The primary impact of PET imaging is in extrathoracic staging, but it should not replace a clinical evaluation by a physician experienced in lung cancer. PET imaging is most useful for confirmation of the presumed extrathoracic stage in patients with intermediate stages of lung cancer. The role of PET imaging is limited in patients with strong clinical signs of metastatic disease, or in patients with a clinical stage I lung cancer and a negative clinical evaluation. With regard to intrathoracic staging, PET imaging has a definite role in communities in which mediastinoscopy is not available, whereas the impact is limited in institutions in which invasive mediastinal staging is available. The data suggest that a positive PET result in the mediastinum should be confirmed by biopsy. A mediastinoscopy is also reasonable in patients with clinical stage III lung cancer who have no mediastinal PET uptake. It is unclear and controversial whether a biopsy is needed in patients with clinical stage II lung cancer who have no PET uptake in the mediastinum.

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.

The noninvasive staging of non-small cell lung cancer: the guidelines

Correctly staging lung cancer is extremely important because the treatment options and the prognosis differ significantly by stage. Several noninvasive imaging studies are available to aid in identifying disease both within and outside of the chest. Chest CT scanning is useful in providing anatomic detail that better identifies the location of the tumor, its proximity to local structures, and whether or not lymph nodes in the mediastinum are enlarged. Unfortunately, the accuracy of chest CT scanning in differentiating benign from malignant lymph nodes in the mediastinum is unacceptably low. Whole-body positron emission tomography (PET) scanning provides functional information on tissue activity and has much better sensitivity and specificity than chest CT scanning for staging lung cancer in the mediastinum. In addition, metastatic disease can be detected by PET scan. Still, positive findings of PET scans can occur from nonmalignant etiologies (eg, infections), so that tissue sampling to confirm the suspected malignancy must be performed. The clinical evaluation tool, which is composed of a thorough history and physical examination, remains the best predictor of metastatic disease. If the findings from the clinical evaluation are negative, then imaging studies such as a CT scan of the head, a bone scan, or an abdominal CT scan are unnecessary, and the search for metastatic disease is complete. If signs, symptoms, or findings from the physical examination suggest the presence of malignancy, then sequential imaging, starting with the most appropriate study based on the clues obtained by the clinical evaluation, should be performed. Abnormalities detected by all of the aforementioned imaging studies are not always cancer. Unless overwhelming evidence of metastatic disease is present on an imaging study, in situations in which it will make a difference in treatment, all abnormal scan findings require tissue confirmation of malignancy so that patients are not precluded from having potentially curative surgery.

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.

Extrathoracic staging of non-small cell bronchogenic carcinoma: relationship of the clinical evaluation to organ scans

OBJECTIVE

The aim of this study was to investigate the value of systemic evaluation of extrathoracic extension of non-small cell lung cancer and to assess the value of the clinical evaluation in detecting extrathoracic metastases.

METHODOLOGY

The study included 90 patients [87 men, three women; mean age 57.5 years (range 28-76)] with potentially resectable non-small cell carcinoma. Fifty-two were squamous cell carcinomas and 38 were adenocarcinomas. Organ-specific and non-organ-specific clinical findings suggesting metastases were analysed and computed tomographic scans of the brain and abdomen and whole-body bone scanning were performed in all patients.

RESULTS

Extrathoracic metastases were detected in 23 (25.5%) of 90 patients. The metastases were located in the following areas: brain (n = 12, 13.3%); bone (n = 9, 10%); liver (n = 5, 5.6%); and adrenal gland (n = 5, 5.5%). Histological analysis revealed metastases in 21.1% (11/52) of the squamous cell carcinomas and 31.6% (12/38) of the adenocarcinomas (P > 0.05). Eleven (47.8%) of the 23 patients with extrathoracic metastases had no organ-specific clinical findings suggesting metastases. Eight patients with squamous cell carcinomas were intrathoracic T1N0 stage and in two (25%) of these patients extrathoracic metastases were detected. These patients had no organ-specific or non-organ-specific clinical factors suggesting metastases.

CONCLUSIONS

Evaluation of extrathoracic extension should be routinely performed in all patients with newly diagnosed lung cancer. This approach will prevent many unnecessary thoracotomies.

[Influence of computed tomography of the abdomen for staging lung cancer]

OBJECTIVES

To analyze the influence of routine imaging of the upper abdomen by conventional computed tomography (CT) to stage bronchopulmonary carcinoma and to detect liver or adrenal metastasis. A second objective was to describe the characteristics of a large group of patients in our practice.

MATERIAL AND METHODS

Retrospective study of 387 patients (367 men and 20 women; mean age [+/-SD] 62.3 +/- 10.4 years, range 34-90 years) who had received a diagnosis of lung cancer (203 epidermoid carcinoma, 75 adenocarcinoma, 15 non-small cell carcinoma, 68 small cell carcinoma and 25 mixed tumors). CT images were obtained of the chest and upper abdomen with intravenous contrast except in patients with a history of allergy or renal insufficiency. The characteristics associated with abdominal CT images aiding or confusing diagnosis were analyzed by Spearman coefficient. Differences related to sex or histology were studied using a Mann-Whitney U-test and Kruskal-Wallis test.

RESULTS

The upper abdominal CT changed the staging of 27 patients (7%): non-small cell carcinoma 5% (16/319) and small-cell carcinoma 16.2% (11/68). Twelve patients (3.1%) showed evidence of unconfirmed adrenal or hepatic metastasis. Change of staging after CT was associated with a high creatinine concentration in blood (p = 0.032), whereas confusion of diagnosis after CT was more common for women (p = 0.002) and patients for whom the diagnosis was established by cytology of sputum or bronchial aspirate (p = 0.019). Differences between men and women were found for from pathology (p = 0.027), confusion after CT (p = 0.002), hemoglobin (p = 0.011), hematocrit (p = 0.019) and smoking (p = 0.000).

CONCLUSION

Given the considerable limitations of CT imaging of the upper abdomen, new technologies should be developed to facilitate a more rational approach to the problem.

Clinical and surgical staging of non-small cell lung cancer

The necessity for a compulsive attitude toward preoperative assessment of lung cancer is to be emphasized, since rational treatment and prognosis depend largely on the stage of disease at the time of diagnosis. In the preoperative setting, the techniques used should be sequential, logical, and help to identify patients suitable for treatment with curative intent. With regard to the primary tumor (T status), the accuracy of CT or MRI to predict the need for extended resections is limited. Similarly, all noninvasive methods to determine the nodal status (N) are valuable, but mediastinoscopy has a greater sensitivity and specificity than either CT or MRI. The role of routine organ screening for the detection of distant occult metastasis in the asymptomatic patient is still controversial. Ultimately, the prognosis of the resected patient with lung cancer is based on complete intraoperative staging, which can be done by either systematic node sampling or complete lymphadenectomy. At present, neither of these techniques has been shown to improve the quality of staging or survival.

Noninvasive clinical staging modalities for lung cancer

Clinical staging of lung cancer helps to determine the extent of disease and stratify patients into similar therapeutic and prognostic categories. A primary goal of clinical staging is to separate patients with potentially resectable disease from those that are unresectable. Initial assessment of the patient by history and physical examination combined with laboratory values can suggest metastatic spread of the disease. When abnormal, these clinical factors may have value in terms of predicting prognosis, but their use in early stage lung cancer is limited because of the low prevalence of symptoms, physical exam findings, and laboratory abnormalities in this group. For clinical staging, patients almost always undergo a postero-anterior and lateral chest radiograph and a computed tomography (CT) scan of the chest and upper abdomen to include the liver and adrenal glands. Although CT scanning provides exquisite anatomic information, it is less than optimal for determining lymph node status. Over the last several years, CT scanning combined with positron-emission tomography (PET) using fluorodeoxyglucose (FDG) has significantly improved the accuracy of clinical staging. The use of FDG-PET continues to be defined in the non-invasive evaluation of the primary tumor, nodal involvement, and metastatic disease. Despite the recent advancements in radiologic assessment of lung cancer, invasive sampling is still often performed for pathologic confirmation.

Non-small-cell lung cancer: practice patterns of extrathoracic imaging

RATIONALE AND OBJECTIVES

The purpose of this study was to identify practice patterns of extrathoracic imaging in patients newly diagnosed with non-small-cell lung, cancer.

MATERIALS AND METHODS

The authors retrospectively reviewed the charts of 125 patients (71 men, 54 women; mean age, 67 years) from five hospitals (25 patients each) with newly diagnosed non-small-cell lung cancer. Charts were reviewed for cancer cell type, evidence of metastatic disease, and performance and results of extrathoracic imaging, including computed tomography (CT) and magnetic resonance (MR) imaging of the brain, bone scanning, and abdominal CT.

RESULTS

Of 125 patients, 77 (62%) underwent extrathoracic imaging. These patients included 64 (64%) of 100 patients with clinical symptoms or laboratory signs of metastatic disease and 13 (52%) of 25 patients with no such indications. Extrathoracic imaging did not differ according to cancer cell type: It was performed for 30 (60%) of 50 patients with squamous cell carcinoma, 26 (60%) of 43 patients with adenocarcinoma, and 16 (73%) of 22 patients with non-small-cell lung cancer that was not further characterized. Brain CT or MR imaging bone scanning, or abdominal CT were performed in only 48%, 39%, and 30% of patients, respectively. Brain CT or MR images or bone scans revealed metastatic disease in seven of 20 and nine of 22 patients with clinical symptoms or laboratory signs of disease, respectively. These examinations revealed disease in four of 40 and two of 27 patients without such symptoms or signs, respectively (P < .05). No significant differences emerged among the practice patterns at the five participating hospitals.

CONCLUSION

No consensus was found on performance of extrathoracic imaging in patients with newly diagnosed non-small-cell lung cancer.

Suspected non-small cell lung cancer: incidence of occult brain and skeletal metastases and effectiveness of imaging for detection--pilot study

PURPOSE

To estimate the incidence of occult metastases to the brain and skeleton in patients suspected of having non-small cell lung cancer (NSCLC) (stage higher than T1Nomo) with surgically resectable disease, to assess the accuracy of screening magnetic resonance (MR) imaging and radionuclide bone scanning for help in identifying occult metastases, and to determine the effectiveness of a high dose of MR contrast material.

MATERIALS AND METHODS

Twenty-nine patients suspected of having NSCLC localized to the lung or to the lung and regional nodes underwent preoperative MR imaging with contrast material enhancement and radionuclide bone scanning for detection of brain or skeletal metastases. Patients were followed up for 12 months to determine the incidence of clinical metastatic disease.

RESULTS

Eight (28%) patients had occult metastatic disease to the brain or skeleton. Brain metastases were identified on MR images in five of six patients. Bone metastases were identified on MR images in four of five patients and on bone scans in three of five patients. MR imaging was no more accurate than bone scanning for skeletal evaluation. A high dose of MR contrast material allowed detection of more metastases and of small lesions.

CONCLUSION

Contrast-enhanced MR imaging of the brain is indicated for the exclusion of brain metastases in patients with clinically operable known or possible NSCLC and a large (> 3-cm) lung mass. Skeletal imaging may be indicated if an isolated brain metastasis is detected.

Transcutaneous abdominal ultrasonography in the staging of lung cancer

BACKGROUND

There is limited information available regarding the relationship between clinical indicators of widespread disease in patients with lung cancer and the findings of transcutaneous ultrasonography.

METHODS

A retrospective survey was made of 279 consecutive patients with lung cancer. By reviewing the patients' records the clinical findings were divided into symptoms, signs, and laboratory tests indicative of metastatic disease. All patients had been examined by abdominal ultrasonography.

RESULTS

The patients included 19% with small cell carcinoma. The frequency of abdominal metastases by ultrasonography in those with small cell carcinoma was 40%, in the other patients it was 8%. Regardless of histological group, all the 40 patients with abdominal metastases by ultrasonography had at least one clinical category indicative of widespread disease and 38 (95%) had two or all three clinical categories positive. Fifty nine patients had no clinical indicators of metastases and none of these had abdominal metastases by ultrasonography.

CONCLUSIONS

The results of this study indicate that abdominal metastases are found in lung cancer patients with clinical findings indicative of widespread disease. No abdominal metastases were found in patients with a negative clinical evaluation. The results indicate that transcutaneous ultrasonography of the abdomen is not necessary in the initial staging if the clinical evaluation is unremarkable.

Possible overlapping potentials of the auditory P50 in humans: factor analysis of middle latency auditory evoked potentials

The auditory P50 in humans may consist of overlapping potentials. To test this hypothesis, we manipulated the conditions of stimulus discrimination and motor response difficulty and evaluated the data by factor analysis. Twenty right-handed males (mean age 27 years) performed the following 4 tasks: (1) a counting task, (2) an easy Go, No-Go task, (3) a difficult Go, No-Go task, and (4) a choice reaction task. Middle latency auditory evoked potentials were obtained with 100 times summation triggered by the onset of the auditory stimulus. Four factors were extracted by factor analysis for a 0-100 ms time period. Factor 1, the maximum factor loading at 91 ms, corresponded to N1, and factor 4, the maximum factor loading at 23 ms, appeared to correspond to P30. The latency of the maximum factor loading in factor 2 was adjacent to that in factor 3, the latency of factor 2 being 12 ms earlier than that of factor 3. Factor 2 and factor 3 latencies were approximately 55 ms which corresponded to the P50. Factor 3 started rising at the point that factor 2 reached the maximum factor loading, and the factor score demonstrated a significant group difference only when analyzed by motor response criteria. These results suggest that the P50 in humans consists of overlapping potentials and that a part of the potential might relate to a motor response process.

Staging non-small cell lung cancer by whole-body positron emission tomographic imaging

BACKGROUND

A need exists for an accurate, noninvasive means of staging non-small cell lung cancer.

METHODS

A prospective evaluation of regional and whole-body positron emission tomography (PET) imaging for staging lung cancer was carried out in 99 patients. Mediastinal PET and computed tomography findings were compared with results of surgical staging in 76 patients. Those PET and computed tomography findings that indicated possible distant metastasis were compared with biopsy results and the results of clinical and imaging follow-up.

RESULTS

Sensitivity and specificity for the diagnosis of N2 disease were 83% and 94% for PET and 63% and 73% for computed tomography, respectively. Positron emission tomography showed previously unsuspected distant metastasis in 11 patients (11%), with no demonstrated false-positive results. Normal PET findings were obtained at distant sites of computed tomography abnormality in 19 patients (19%). Clinical and imaging follow-up in 14 of these patients showed no evidence of metastasis. In 1 case, the PET result proved to be falsely negative.

CONCLUSIONS

Imaging with PET was more accurate than computed tomography for diagnosis of mediastinal and distant metastasis. Detection of unsuspected metastatic disease by PET may permit reduction in the number of thoracotomies performed for nonresectable disease.

Cost-effectiveness of head CT in patients with lung cancer without clinical evidence of metastases

OBJECTIVE

To estimate the cost-effectiveness of CT for detecting brain lesions in patients with lung cancer without clinical evidence of metastases.

DESIGN

Decision analysis model comparing two different strategies for detecting brain metastases: brain CT routinely (CT-first) or brain CT only when patients develop neurologic signs and/or symptoms (CT-deferred).

PATIENTS

Hypothetical cohort of patients with lung cancer with an unremarkable screening clinical evaluation for metastases.

MEASUREMENTS

Net costs are calculated as the difference in costs between the two limbs of the decision tree. Net benefits are expressed as the difference in calculated years of life expectancy between the two strategies. Net costs are divided by net benefits, yielding the marginal cost per quality adjusted year of added life expectancy (C/QALY) for the CT-first strategy.

RESULTS

In the baseline analysis, the C/QALY for the CT-first strategy is about $70,000. Improving the clinical evaluation as a screen for detecting brain metastases markedly increases the C/QALY. Increasing the cost of brain CT magnifies this effect. More effective treatment for asymptomatic brain metastases and better accuracy of CT for identifying resectable and unresectable brain metastases lower C/QALY.

CONCLUSIONS

Although a threshold cost-effectiveness has not been defined for identifying "cost-effective" diagnostic procedures, the marginal C/QALY of the CT-first strategy is substantially higher than many accepted medical interventions. At current costs, the routine use of brain CT is not warranted in patients with lung cancer who have normal findings on a standardized clinical evaluation for metastases.

Preoperative evaluation of stage I and stage II non-small cell lung cancer

The appropriate preoperative evaluation for occult metastasis in patients with potentially resectable lung cancer remains controversial. The records of 265 patients with stage I and II non-small cell lung cancers who underwent resection with curative intent were reviewed to determine if there was a survival benefit of negative preoperative scanning to detect metastases. A minimum of 5 years of follow-up was possible for all long-term survivors. Patients having preoperative bone scans, brain imaging, and abdominal imaging had no increased survival over those without such evaluation (using Kaplan-Meier survival curves). Additionally, no difference was found in the time to first recurrence between these groups, and the site of recurrence was independent of a negative preoperative scan for that location. These data, using patient outcome as the basis of our conclusion, support a policy of reserving expensive preoperative metastatic evaluations only for those patients with clinical evidence of metastatic disease.

Cranial computed tomography as a part of the initial staging procedures for patients with non-small-cell lung cancer

With the possible exception of chemotherapy for the small-cell type, a complete surgical excision is still the only effective treatment of lung cancer. Routine brain computed tomography (CT) for staging purposes has been both advocated and opposed. In this retrospective study, we aimed to assess the clinical yield of the technique. We saw 184 consecutive patients with a new histologically proven non-small-cell lung cancer. Using as reference criteria clinical judgment supported by a strict follow-up evaluation, we counted 1 false- and 23 true-positive brain CT results, plus 2 false- and 158 true-negative findings. These figures allow for sensitivity, specificity, and accuracy of 92 percent, 99 percent, and 98 percent. The frequency of brain metastases did not correlate with the various histologic types, even though adenocarcinoma was the most common cause of cerebral metastases. The absence of neurologic symptoms did not exclude cerebral involvement: in our experience, 16 of 25 patients with positive brain CT scans were asymptomatic (64 percent). Three of 31 subjects (10 percent) with an otherwise operable carcinoma were found to have metastases after brain CT. We conclude that routine cranial CT is useful in the staging evaluation of the patient with non-small-cell lung cancer (NSCLC) and that it should be performed in any candidate prior to surgical resection.

Analysis of published studies on the detection of extrathoracic metastases in patients presumed to have operable non-small cell lung cancer

BACKGROUND

A study was undertaken to determine the proportion of patients with potentially operable non-small cell lung cancer that could be spared thoracotomy by a systematic search for extrathoracic metastases.

METHODS

An English language literature search was carried out using MEDLINE (1966-91) and bibliographic reviews of textbooks, review articles, and key articles. Studies were included in which at least 90% of the patients had histologically proven non-small cell cancer of the lung, were presumed otherwise operable, and for which the results of computed tomography of the head or abdomen, ultrasonography of the abdomen, or radionuclide imaging (scan) of bone or liver were available. Study quality and specific descriptive information concerning population, intervention, and outcome measurements were assessed.

RESULTS

Of approximately 1500 citations which were screened, 100 were reviewed in detail and data abstracted from 16. The number of patients (total number, followed in square brackets by number of asymptomatic patients) shown to be inoperable directly as a result of the investigation and thus spared unnecessary thoracotomy was: computed tomography of the head: 26/785 (3.3%), 95% confidence interval (CI) 2.1% to 4.4% [14/353 (4.0%), 95% CI 2% to 6%], computed tomography of the adrenal glands: 30/632 (4.7%), 95% CI 3.0% to 6.4% [number asymptomatic indeterminate], bone scan: 45/480 (9.3%), 95% CI 6.7% to 12% [9/301 (3.0%), 95% CI 1.1% to 4.9%], liver imaging: 12/529 (2.3%), 95% CI 0.9% to 3.3% [4/268 (1.5%), 95% CI 0.1% to 3%].

CONCLUSIONS

A study with a large sample size and preferably incorporating thoracic computed tomography is required to narrow the confidence intervals around each test. All tests may play an important part in the preoperative evaluation of patients with non-small cell carcinoma of the lung who are presumed to be operable, including asymptomatic patients. Limitations of present data preclude definitive recommendations for asymptomatic patients.

Staging for M disease

The presence of distant metastatic disease (M disease) in non-small-cell cancer patients is associated with a poor prognosis, and surgical resection at the primary site is contraindicated. Careful preoperative evaluation to identify the subset of patients presenting with M disease is essential in order to avoid unnecessary surgery. Current indications for the use of diagnostic techniques and the methods utilized to detect metastatic disease at the commonest sites encountered in patients with non-small-cell carcinoma, including the pleura, central nervous system, liver, adrenal glands, and skeletal system, are discussed.

The relationship of clinical findings to CT scan evidence of adrenal gland metastases in the staging of bronchogenic carcinoma

OBJECTIVE

To determine whether, during the staging of newly diagnosed bronchogenic carcinoma, clinical indicators predict the presence or absence of adrenal metastases detected by computerized tomographic (CT) scans.

DESIGN

Retrospective review of charts and roentgenograms.

SETTING

Academic medical center.

PATIENTS

Two hundred five consecutive patients diagnosed with bronchogenic carcinoma, of whom 173 had sufficient data available for analysis.

MEASUREMENTS

Charts were reviewed for abnormalities in three clinical categories (signs, symptoms, and routine laboratory tests) and the presence of extrapulmonary tumor spread. The CT scans were reviewed for evidence of adrenal involvement by radiologists blinded to clinical findings.

MAIN RESULTS

Thirty patients had abnormal adrenal glands on CT scan. In 26 the abnormality was believed to represent adrenal metastasis, whereas in four the CT findings were consistent with adrenal adenomas. The frequency of adrenal metastases varied with the number of positive, clinical findings (chi 2 = 105.4; p < 0.001). All 26 patients with adrenal metastases had at least one clinical abnormality, and 21 (81 percent had abnormalities in either two or all three clinical categories. In 40 patients without any clinical indicators of widespread disease, none had CT evidence of adrenal metastases. The presence of adrenal metastases also varied with the extent of coexistent disease (chi 2 = 111.82; p < 0.001). Eighty-one percent (21) of the patients with and 18 percent of those without adrenal metastases had both intrathoracic and extrathoracic involvement.

CONCLUSIONS

Our findings indicate that adrenal metastases are found in patients with a large tumor burden who have clinical indicators of widespread disease. We found no evidence of adrenal metastases by CT in any patient with a normal clinical evaluation. We conclude that CT scans through the adrenal glands are unnecessary when staging newly diagnosed bronchogenic carcinoma if the findings from the initial clinical evaluation are normal.

Preoperative computed tomography of the brain in non-small cell bronchogenic carcinoma

BACKGROUND

Computed tomography of the brain is the most accurate diagnostic investigation for detecting intracranial tumours. A prospective study was undertaken to try to maximise the cost effectiveness of computed tomography of the brain in the preoperative evaluation of non-small cell lung cancer.

METHODS

All patients with non-small cell lung cancer who were free of neurological symptoms and were thought to be free of metastases from the results of routine investigations were subjected to computed tomography of the brain in the 12-24 hours immediately before surgery.

RESULTS

Of 158 such patients, five showed positive evidence of metastases, confirmed on craniotomy and excision biopsy; one of these patients was found to have a non-metastatic tumour (false positive). Five patients with a negative scan who underwent lung resection returned within 12 months with neurological defects and positive findings on further computed tomography (false negative). The predominant cell type in patients with positive and false negative scans was adenocarcinoma or adenosquamous carcinoma (7/10); the majority had nodal state N2.

CONCLUSIONS

Computed tomography of the brain should be carried out if mediastinal disease is suspected or confirmed in non-small cell lung cancer before proceeding to surgery.

Prophylactic cranial irradiation for lung cancer patients at high risk for development of cerebral metastasis: results of a prospective randomized trial conducted by the Radiation Therapy Oncology Group

Beginning in February 1984, 187 evaluable patients with adenocarcinoma or large cell carcinoma of the lung clinically confined to the chest were randomized to receive either conventionally fractionated thoracic irradiation alone or thoracic irradiation with concurrent, prophylactic cranial irradiation. The study population included 161 patients treated for medically or surgically inoperable primary cancers, and 26 patients undergoing adjuvant postoperative mediastinal irradiation following attempted curative resection of primary cancers found to have metastasized to hilar or mediastinal lymph nodes. Elective brain irradiation was not effective in preventing the clinical appearance of brain metastases, although the time to develop brain metastases appears to have been delayed. Eighteen of 94 patients (19%) randomized to chest irradiation alone have developed brain metastases as opposed to 8/93 patients (9%) randomized to receive prophylactic cranial irradiation (p = .10). No survival difference was observed between the treatment arms. Among the 26 patients undergoing prior resection of all gross intrathoracic disease, brain metastases were observed in 3/12 patients (25%) receiving adjuvant chest irradiation alone, compared to none of 14 receiving prophylactic cranial irradiation (p = .06). In the absence of fully reliable therapy for the primary disease, and without effective systemic therapy preventing dissemination to other, extrathoracic sites, prophylactic cranial irradiation for inoperable non-small cell lung cancer cannot be justified in routine clinical practice. Further investigation in the adjuvant, postoperative setting may be warranted.

Non-small cell lung cancer. Part I: Biology, diagnosis, and staging

Squamous, large cell, and adenocarcinoma, collectively termed non-small cell lung cancer (NSCLC), are diagnosed in approximately 75% of patients with lung cancer in the United States. The treatment of these three tumor cell types is approached in virtually identical fashion because, in contrast to small cell carcinoma of the lung, NSCLC more frequently presents with localized disease at the time of diagnosis and is thus more often amenable to surgical resection but less frequently responds to chemotherapy and irradiation. Cigarette smoking is etiologically related to the development of NSCLC in the great majority of cases. Genetic mutations in dominant oncogenes such as K-ras, loss of genetic material on chromosomes 3p, 11p, and 17p, and deletions or mutations in tumor suppressor genes such as rb and p53 have been documented in NSCLC tumors and tumor cell lines. NSCLC is diagnosed because of symptoms related to the primary tumor or regional or distant metastases, as an incidental finding on chest radiograph, or rarely because of a paraneoplastic syndrome such as hypercalcemia or hypertrophic pulmonary osteoarthropathy. Screening smokers with periodic chest radiographs and sputum cytologic examination has not been shown to reduce mortality. The diagnosis of NSCLC is usually established by fiberoptic bronchoscopy or percutaneous fine-needle aspiration, by biopsy of a regional or distant metastatic site, or at the time of thoracotomy. Pathologically, NSCLC arises in a setting of bronchial mucosal metaplasia and dysplasia that progressively increase over time. Squamous carcinoma more often presents as a central endobronchial lesion, while large cell and adenocarcinoma have a tendency to arise in the lung periphery and invade the pleura. Once the diagnosis is made, the extent of tumor dissemination is determined. Since most NSCLC patients who survive 5 years or longer have undergone surgical resection of their cancers, the focus of the staging process is to determine whether the patient is a candidate for thoracotomy with curative intent. The dominant prognostic factors in NSCLC are extent of tumor dissemination, ambulatory or performance status, and degree of weight loss. Stages I and II NSCLC, which are confined within the pleural reflection, are managed by surgical resection whenever possible, with approximate 5-year survival of 45% and 25%, respectively. Patients with stage IIIa cancers, in which the primary tumor has extended through the pleura or metastasized to ipsilateral or subcarinal lymph nodes, can occasionally be surgically resected but are often managed with definitive thoracic irradiation and have 5-year survival of approximately 15%.(ABSTRACT TRUNCATED AT 400 WORDS)

Invasive and noninvasive techniques of staging in potentially operable lung cancer

The author reviews the various noninvasive and invasive techniques for preoperatively staging patients with lung cancer who are potentially operable. The value of computed tomography and mediastinoscopy is emphasized and their role in treatment decisions is outlined. Prior to consideration of surgery in patients with lung cancer, preoperative staging, as accurate as possible, is required in order to determine the best treatment. Complete staging is only available after surgical resection and pathologic examination.