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

Diagnostic performance of whole-body [18F]FDG PET/MR in cancer M staging: A systematic review and meta-analysis

OBJECTIVES

To calculate the pooled diagnostic performances of whole-body [18F]FDG PET/MR in M staging of [18F]FDG-avid cancer entities.

METHODS

A diagnostic meta-analysis was conducted on the [18F]FDG PET/MR in M staging, including studies: (1) evaluated [18F]FDG PET/MR in detecting distant metastasis; (2) compared[ 18F]FDG PET/MR with histopathology, follow-up, or asynchronous multimodality imaging as the reference standard; (3) provided data for the whole-body evaluation; (4) provided adequate data to calculate the meta-analytic performances. Pooled performances were calculated with their confidence interval. In addition, forest plots, SROC curves, and likelihood ratio scatterplots were drawn. All analyses were performed using STATA 16.

RESULTS

From 52 eligible studies, 2289 patients and 2072 metastases were entered in the meta-analysis. The whole-body pooled sensitivities were 0.95 (95%CI: 0.91-0.97) and 0.97 (95%CI: 0.91-0.99) at the patient and lesion levels, respectively. The pooled specificities were 0.99 (95%CI: 0.97-1.00) and 0.97 (95%CI: 0.90-0.99), respectively. Additionally, subgroup analyses were performed. The calculated pooled sensitivities for lung, gastrointestinal, breast, and gynecological cancers were 0.90, 0.93, 1.00, and 0.97, respectively. The pooled specificities were 1.00, 0.98, 0.97, and 1.00, respectively. Furthermore, the pooled sensitivities for non-small cell lung, colorectal, and cervical cancers were 0.92, 0.96, and 0.86, respectively. The pooled specificities were 1.00, 0.95, and 1.00, respectively.

CONCLUSION

[18F]FDG PET/MR was a highly accurate modality in M staging in the reported [18F]FDG-avid malignancies. The results showed high sensitivity and specificity in each reviewed malignancy type. Thus, our findings may help clinicians and patients to be confident about the performance of [18F]FDG PET/MR in the clinic.

CLINICAL RELEVANCE STATEMENT

Although [18F]FDG PET/MR is not a routine imaging technique in current guidelines, mostly due to its availability and logistic issues, our findings might add to the limited evidence regarding its performance, showing a sensitivity of 0.95 and specificity of 0.97.

KEY POINTS

• The whole-body [18F]FDG PET/MR showed high accuracy in detecting distant metastases at both patient and lesion levels. • The pooled sensitivities were 95% and 97% and pooled specificities were 99% and 97% at patient and lesion levels, respectively. • The results suggested that 18F-FDG PET/MR was a strong modality in the exclusion and confirmation of distant metastases.

Controversies in Mediastinal Staging for Nonsmall Cell Lung Cancer

Mediastinal lymph nodal involvement in nonsmall cell lung cancer plays a crucial role in deciding treatment strategy. Survival falls markedly with increasing involvement of mediastinal nodal stations. Hence, accurate staging of the mediastinum with lowest morbidity is of utmost importance. A wide array of invasive and noninvasive modalities that complement each other in assessing the nodes are available at our disposal. Guidelines recommend noninvasive imaging as the initial step in the staging algorithm for all tumors, followed by invasive staging. No single modality has proven to be the ideal method to stage the mediastinum when used alone. In the present decade, minimally invasive endobronchial ultrasound (EBUS) has challenged the position of surgical mediastinoscopy, which has been the gold standard, historically. However, a negative EBUS needs to be confirmed by surgical mediastinoscopy. Video-assisted mediastinoscopic lymphadenectomy has also come to the forefront in last two decades and has shown exceptional results, when performed in experienced centers. This review details the various modalities of mediastinal staging and the controversies surrounding the optimal method of staging, restaging after neoadjuvant therapy, and the most cost-effective strategy.

Utility of PET-CT in non-small cell lung cancer clinical stage IB-IIA according to AJCC 8th edition staging system: an alternative to invasive mediastinal staging?

Objective

Mediastinal nodal staging in lung cancer is essential to determine treatment strategy and prognosis. There are controversies as to whether a mediastinal negative result in PET-CT may spare the invasive staging of the mediastinum. The main endpoint is to evaluate the negative predictive value (NPV) of PET-CT in non-small cell lung cancer (NSCLC) clinical stage IB-IIA without clinical nodal involvement. The secondary endpoint is to evaluate the prevalence of mediastinal and hilar nodal affection in this population.

Methods

We performed an observational descriptive study from January 2010 to January 2020, including 76 patients with clinical stage IB-IIA, who underwent pulmonary resection with systematic nodal sampling (pre-determined lymph node stations based on tumour location) for primary NSCLC. Clinically, nodal involvement was defined as any lymph node greater than 1 cm in the short axis on a CT or with metabolic uptake greater than 2.5 SUV on PET-CT. The prevalence of nodal metastases was recorded.

Results

Fifty six patients had clinical stage IB and 20 had clinical stage IIA. Mean tumour size was 3.74 ± 0.5 cm. Lobectomy was the resection procedure most frequently performed. Of the 76 patients with clinical N0 by PET-CT who underwent surgical resection, 10 (13.1%) were upstaged to pN1 and none were upstaged to pN2. NPV of PET-CT for overall nodal metastasis was 87% (95% CI: 0.79-0.94). NPV of PET-CT for N2 metastasis was 100%.

Conclusion

PET-CT might be an alternative to invasive mediastinal staging in patients with NSCLC clinical stage IB-IIA who are surgical candidates. Further prospective multi-institutional studies are necessary to verify the external validity of our study.

Resectable IIIA-N2 Non-Small-Cell Lung Cancer (NSCLC): In Search for the Proper Treatment

Locally advanced non-small cell lung cancer accounts for one third of non-small cell lung cancer (NSCLC) at the time of initial diagnosis and presents with a wide range of clinical and pathological heterogeneity. To date, the combined multimodality approach involving both local and systemic control is the gold standard for these patients, since occult distant micrometastatic disease should always be suspected. With the rapid increase in treatment options, the need for an interdisciplinary discussion involving oncologists, surgeons, radiation oncologists and radiologists has become essential. Surgery should be recommended to patients with non-bulky, discrete, or single-level N2 involvement and be included in the multimodality treatment. Resectable stage IIIA patients have been the subject of a number of clinical trials and retrospective analysis, discussing the efficiency and survival benefits on patients treated with the available therapeutic approaches. However, most of them have some limitations due to their retrospective nature, lack of exact pretreatment staging, and the involvement of heterogeneous populations leading to the awareness that each patient should undergo a tailored therapy in light of the nature of his tumor, its extension and his performance status.

Development and validation of a novel diagnostic model for assessing lung cancer metastasis in a Chinese population based on multicenter real-world data

Background

Accurate disease staging plays an important role in lung cancer's clinical management. However, due to the limitation of the CT scan, it is still an unmet medical need in practice. In the present study, we attempted to develop diagnostic models based on biomarkers and clinical parameters for assessing lung cancer metastasis.

Methods

This study consisted of 799 patients with pulmonary lesions from three regional centers in China. It included 274 benign lesions patients, 326 primary lung cancer patients without metastasis, and 199 advanced lung cancer patients with lymph node or organ metastasis. The patients were divided into nodules group and masses group according to tumor size.

Results

Four nomogram models based on patient characteristics and tumor biomarkers were developed and evaluated for patients with nodules and masses, respectively. In patients with pulmonary nodules, the AUC to identify metastatic lung cancer from unidentified nodules (including benign nodules and lung cancer, model 1) reached 0.859 (0.827–0.887, 95% CI). Model 2 was used to predict metastasis in patients with lung cancer with AUC of 0.838 (0.795–0.876, 95% CI). In patients with pulmonary masses, the AUC to identify metastatic lung cancer from unidentified masses (model 3) reached 0.773 (0.717–0.823, 95% CI). Model 4 was used to predict metastasis in patients with lung cancer and AUC reached 0.731 (0.771–0.793, 95% CI). Decision curve analysis corroborated good clinical applicability of the nomograms in predicting metastasis.

Conclusion

All new models demonstrated promising discrimination, allowing for estimating the risk of lymph node or organ metastasis of lung cancer. Such integration of blood biomarker testing with CT imaging results will be an efficient and effective approach to benefit the accurate staging and treatment of lung cancer.

The Contribution of Fluorine 18F-FDG PET/CT to Lung Cancer Diagnosis, Staging and Treatment Planning

Objective:

Lung cancer is the most common cause of cancer-related death throughout the world, and the correct choice of treatment based on early diagnosis and staging increases the chance of survival. The present study aims to investigate the contribution of fluorine 18-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) to the management of lung cancer.

Methods:

In this study, 50 patients who underwent ¹⁸F-FDG PET/CT for lung cancer diagnosis and staging between February 2012 and February 2014 were included. The maximum standardized uptake value (SUV_max) of the primary lung lesion along with other findings of ¹⁸F-FDG PET/CT and the results of histopathologic and conventional examinations were evaluated retrospectively. The mean survival time of patients was determined, and the findings were compared by using statistical methods.

Results:

Histopathologic examinations revealed 51 lung cancers in 50 patients. The sensitivity, accuracy and positive predictive value of ¹⁸F-FDG PET/CT in detecting primary malignancy were 94%, 94%, 100%, respectively. Adenocarcinoma (n=23, 16.8±13.5) and squamous cell carcinoma (n=15, 17.9±5.6) did not differ significantly regarding their mean SUV_max values (p=0.2). A statistically significant positive correlation (r=0.4) was identified between tumor size and SUV_max value for 51 tumors (p=0.002). The ¹⁸F-FDG PET/CT result was true negative in nine, false positive in six, true positive in two, and false negative in four patients who underwent histopathologic evaluation of their lymph nodes. The ¹⁸F-FDG PET/CT changed treatment planning in 34% of the patients. No significant relationship was identified between SUV_max value of the tumor and patient survival in patients (p=0.118).

Conclusion:

The present study concluded that PET/CT was an efficient method in the diagnosis and staging of lung cancer since it provided useful information in addition to conventional methods. It was also observed that PET/CT scanning resulted in a change in therapeutic plans in the majority of patients. However, there was no statistically significant relationship between survival and the SUV_max of the primary mass.

The role of endobronchial ultrasound/esophageal ultrasound for evaluation of the mediastinum in lung cancer

The introduction: of ultrasound-based, minimally invasive techniques (Endobronchial Ultrasound guided Transbronchial Needle Aspiration (EBUS-TBNA) and Esophageal Ultrasound guided Fine Needle Aspiration) has revolutionized care of patients with lung cancer needing mediastinal lymph node sampling. When combined, the techniques offer safe and accurate assessment of mediastinum, with accuracy surpassing that of the pervious gold standard - cervical mediastinoscopy. EBUS-TBNA can be used for mediastinal restaging in both, patients with suspected recurrence following treatment for primary lung cancer and followingneoadjuvant therapy in preparation for definitive surgical intervention. Both EBUS-TBNA and esophageal ultrasound guided fine needle aspiration techniques have been shown to provide sufficient material for molecular and DNA testing, extending their role beyond initial evaluation of the mediastinum to help direct and personalize medical treatment and predict response to therapy. In the future, assessing sonographic features of lymph nodesmay become useful in predicting nodal metastasis, further increasing the sensitivity of these techniques for detection of metastatic disease.

Colonic metastasis after resection of primary squamous cell carcinoma of the lung: A case report and literature review

Lung cancer is a common malignancy in the world; however symptomatic colonic metastasis from primary lung cancer is rare. A 64-year-old man was originally found poorly differentiated squamous cell carcinoma of right lung and received right lower lobectomy and lymph node dissection. Three years later, the patient presented to our emergency room with the symptom of upper abdominal pain and weight loss. Abdominal palpation and computed tomography scan of the abdomen revealed a large mass measuring 7.6 cm × 8.5 cm in the ascending colon. Colonoscopy and biopsy revealed poorly differentiated squamous cell carcinoma with similar morphological pattern to that of the previous lung cancer. Chemotherapy was given and the patient died 5 mo later. Lung cancer metastatic to the colon confers a poor prognosis: overall survival ranged from 5 wk to 1 year, with a median survival of 3 mo after the diagnosis of the colonic metastasis.

PGK1 as predictor of CXCR4 expression, bone marrow metastases and survival in neuroblastoma

Background and Aim

A close relationship between phosphoglycerate kinase 1 (PGK1) and the CXCR4/SDF1 axis (chemokine receptor 4/stromal cell derived factor 1) has been shown for several cancers. However, the role of PGK1 has not been investigated for neuroblastoma, and PGK1 might be a therapeutic target for this tumor entity. The aim of the current study was to evaluate the role of PGK1 expression in neuroblastoma patients, to determine the impact of PGK1 expression levels on survival, and to correlate PGK1 expression with CXCR4 expression and bone marrow dissemination.

Materials and Methods

Samples from 22 patients with neuroblastoma that were surgically treated at the University Medical Center Hamburg-Eppendorf were evaluated for expression of PGK1 and CXCR4 using immunohistochemistry. Results were correlated with clinical parameters, metastases and outcome of patients. Immunocytochemistry, proliferation and expression analysis of CXCR4 and PGK1 were performed in neuroblastoma cell lines.

Results

PGK1 is expressed in neuroblastoma cells. PGK1 expression is significantly positively correlated with CXCR4 expression and tumor dissemination to the bone marrow. Moreover the expression of PGK1 is significantly associated with a negative impact on survival in patients with neuroblastoma. PGK1 is downregulated by inhibition of CXCR4 in neuroblastoma cells.

Conclusion

PGK1 appears to play an important role for neuroblastoma, predicting survival and tumor dissemination. Further in vivo studies outstanding, it is a candidate target for novel therapeutic strategies.

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.

The use and misuse of positron emission tomography in lung cancer evaluation

This article discusses the potential benefits and limitations of positron emission tomography (PET) for characterizing lung nodules, staging the mediastinum, identifying occult distant metastasis, determining prognosis and treatment response, guiding plans for radiation therapy, restaging during and after treatment, and selecting targets for tissue sampling. The key findings from the medical literature are presented regarding the capabilities and fallibilities of PET in lung cancer evaluation, including characterization of pulmonary nodules and staging in patients with known or suspected non-small-cell lung cancer. The discussion is limited to PET imaging with fluorodeoxyglucose.

Activated carbon nanoparticles or methylene blue as tracer during video-assisted thoracic surgery for lung cancer can help pathologist find the detected lymph nodes

BACKGROUND

To assess whether using methylene blue (MB) or activated carbon nanoparticles as tracer can increase the detected number of lymph nodes in the systematic nodal dissected tissue during Video-Assisted Thoracic Surgery (VATS) for non-small cell lung cancer.

METHODS

Three groups of 20 patients each were obtained from randomization of 60 patients with NSCLC requiring VATS with systematic nodal dissection (SND) from February 2007 and December 2008, there were 17, 16, and 17 patients in group A (injection activated carbon nanoparticles), group B (injection MB), and group C (controls), respectively.

RESULTS

There was difference of the total number of dissected lymph nodes per patient among three groups (P < 0.001). The total number of dissected LNs and mediastinal nodes per patient in group A and group B was more than in group C (P < 0.001). There were 20, 18, and 14 metastatic LNs dissected in 6, 6, and 7 patients of group A, B, and C, respectively. There was difference of total number of dissected metastatic LNs per patient among three groups (P = 0.002).

CONCLUSIONS

MB can be as effective as activated carbon nanoparticles being tracer to increase the detected number of LNs in the systematic nodal dissected tissue during VATS for NSCLC.

[Application of videomediastinoscopy in positive PET finding for mediastinal lymph node of lung cancer]

BACKGROUND AND OBJECTIVE

Positron emission tomography (PET) is used increasingly in staging of non-small cell lung cancer (NSCLC) as a non-invasive tool. However, the role of PET in mediastinal lymphatic staging of NSCLC is not clear. The aim of this study was to demonstrate the efficacy of mediastinoscopy in determining mediastinal lymphatic metastasis in cases of positive PET finding.

METHODS

We performed PET preoperatively in 68 patients with clinically operable NSCLC between 2003 and 2008. Mediastinal lymphatic defined as metastasis by PET (SUV(max) > 2.5) was recorded. Mediastinoscopy being performed initially in all patients. Involvement of mediastinal lymph nodes was verified to compare the sensitivity and specificity of mediastinoscopy and the related PET results.

RESULTS

From 2003 to 2008, 61 mediastinoscopy were performed. There were 38 men and 23 women, aged from 41 to 81 years (mean 60 years). Localization of the tumor was right lung in 41 patients and left lung in 20 patients. After the operation, 45 patients were demonstrated to have N2 or N3 disease. Ten patients with N3 mediastinal metastasis for chemotherapy, 38 patients with N2 mediastinal metastasis for neuadjuvant chemotherapy while lung resection and systemic mediastinal lymphatic dissection through thoracotomy was performed in the remaining 16 patients with no mediastinal metastasis. The positive prediction value of PET scan was 73.8% (45/61). The sensitivity, specificity, accuracy, positive prediction value and negative prediction value in diagnosis of metastasis of mediastinal lymph nodes were 93.8% (45/48), 100% (13/13), 95.1% (58/61), 100% (45/45), 81.3% (13/16) for mediastinoscopy, respectively.

CONCLUSION

PET results do not provide acceptable accuracy rates. Mediastinoscopy still remains the gold standard for mediastinal staging of NSCLC.

Expression of PGK1 by prostate cancer cells induces bone formation

Prostate cancer (PCa) is one of the solid tumors that metastasize to the bone. Once there, the phenotype of the bone lesions is dependent upon the balance between osteoblastogenesis and osteoclastogenesis. We previously reported that overexpression of phosphoglycerate kinase 1 (PGK1) in PCa cell lines enhanced bone formation at the metastatic site in vivo. Here, the role of PGK1 in the bone formation was further explored. We show that PCa-derived PGK1 induces osteoblastic differentiation of bone marrow stromal cells. We also found that PGK1 secreted by PCa inhibits osteoclastogenesis. Finally, the expression levels of the bone-specific markers in PCa cells were higher in cells overexpressing PGK1 than controls. Together, these data suggest that PGK1 secreted by PCa regulates bone formation at the metastatic site by increasing osteoblastic activity, decreasing osteoclastic function, and expressing an osteoblastic phenotype by PCa cells.

18F-FDG PET/CT in mediastinal lymph node staging of non-small-cell lung cancer in a tuberculosis-endemic country: consideration of lymph node calcification and distribution pattern to improve specificity

PURPOSE

The aim of the study was to assess the accuracy of (18)F-fluorodeoxyglucose (FDG) PET/CT in mediastinal lymph node staging of patients with non-small-cell lung cancer (NSCLC) in a region with a high prevalence of granulomatous disease.

METHODS

Between March 2004 and February 2006, all patients with NSCLC underwent FDG PET/CT and contrast-enhanced thoracic CT, and subsequent surgical resection. PET/CT and contrast-enhanced CT images of 182 patients (126 men and 56 women; mean age 60.7 years) with NSCLC were acquired. Mediastinal node staging was determined using the American Joint Committee on Cancer (AJCC) staging system. Surgical and histological findings served as the reference standard.

RESULTS

A total of 182 patients with 778 mediastinal node stations were evaluated. Sensitivity and specificity of contrast-enhanced CT were 36% and 80% on a per-patient basis and 23% and 92% on a per-node station basis. Sensitivity and specificity of PET/CT were 81% and 73% on a per-patient basis and 75% and 85% on a per-node station basis. After lymph nodes with calcification and bilateral hilar distribution were considered benign, sensitivity and specificity of PET/CT were 75% and 89% on a per-patient basis and 66% and 96% on a per-node station basis.

CONCLUSION

This prospective study suggests that FDG PET/CT can more accurately stage mediastinal lymph nodes than CT. Considering lymph node calcification and distribution pattern could improve specificity at the cost of a decrease in sensitivity.

Lung cancer metastasis to the scapula and spine: a case report

BACKGROUND

The objective of this case report is to describe the clinical presentation of a patient who complained of shoulder pain and was diagnosed with carcinoma of the scapula and spine that metastasized from the lung.

CASE PRESENTATION

A 76-year-old man without a history of cancer sought chiropractic care for right shoulder pain. Careful evaluation, radiographs, and subsequent imaging revealed primary and metastatic lung cancer. The patient was referred to his primary care physician for immediate medical care. Diagnostic images are included in this case to provide a comprehensive depiction of the scope of the patient's disease.

CONCLUSION

Musculoskeletal symptoms are commonly encountered in chiropractic practice. It is important to recognize that primary lung cancer may be unidentified, and musculoskeletal symptoms may reflect the first sign of primary or metastatic pulmonary disease. Thoughtful evaluative procedure and clinical decision making, combined with the use of appropriate diagnostic tests may allow timely identification of primary or metastatic disease.

Glut-1 antibodies induce growth arrest and apoptosis in human cancer cell lines

Glucose transporters (Gluts) facilitate glucose uptake and tumors frequently over express the Gluts, especially Glut-1. Breast cancer and lung cancer (NSCLC) cell lines were incubated with anti-Glut-1 antibodies alone or with cisplatin, paclitaxel or gefitinib. Inhibition of proliferation and apoptosis was assessed. Antibodies to Glut-1 inhibited proliferation by 50% and 75% in the tested NSCLC and breast cancer cell lines, respectively. They also potentiate the anti-proliferative effects of cisplatin, paclitaxel and gefitinib. Our results indicate that anti-Glut-1 antibodies inhibit proliferation and induce apoptosis in the evaluated cell lines and provide preliminary evidence of their anti-tumor activity.

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.

Beliefs among Physicians in the Diagnostic and Therapeutic Approach to Non-small Cell Lung Cancer

PURPOSE

The American College of Chest Physicians (ACCP) has established evidence-based guidelines for the evaluation and treatment of patients with lung cancer. Physicians' beliefs and practice patterns may differ significantly from established guidelines. We conducted a survey to assess and compare physician beliefs against the evidence-based guidelines.

METHODS

A survey was sent by electronic mail (e-mail) in March 2006 to 2100 randomly selected physicians who were members of the ACCP practicing in the United States, followed by two reminder e-mails.

RESULTS

Three hundred forty-seven surveys were completed and evaluable. The majority (84%) of the respondents reported having read, consulted, or used the guidelines to set practice policies, and 75% found the guidelines helpful. The respondents' practice beliefs were in agreement with the guidelines on the evaluation of operable patients with enlarged mediastinal lymph nodes, the role of chemotherapy in the treatment of stage III disease, and the evaluation of a solitary pulmonary nodule. Nevertheless, a significant percentage of respondents' practice beliefs differed from the guidelines on issues such as screening for lung cancer, the survival benefit of chemotherapy in stage IV disease, and postoperative radiation therapy. Only a minority of respondents believed that chemotherapy improved quality of life in stage IV disease. The survey results indicate that there has been acceptance of the adjuvant chemotherapy and increasing integration of positron emission tomography in the evaluation of a solitary pulmonary nodule and in staging the mediastinum.

CONCLUSIONS

The majority of physicians found the evidence-based guidelines beneficial; nevertheless, practice beliefs differ from the guidelines in select areas.

A glycolytic mechanism regulating an angiogenic switch in prostate cancer

The generation of an "angiogenic switch" is essential for tumor growth, yet its regulation is poorly understood. In this investigation, we explored the linkage between metastasis and angiogenesis through CXCL12/CXCR4 signaling. We found that CXCR4 regulates the expression and secretion of the glycolytic enzyme phosphoglycerate kinase 1 (PGK1). Overexpression of PGK1 reduced the secretion of vascular endothelial growth factor and interleukin-8 and increased the generation of angiostatin. At metastatic sites, however, high levels of CXCL12 signaling through CXCR4 reduced PGK1 expression, releasing the angiogenic response for metastastic growth. These data suggest that PGK1 is a critical downstream target of the chemokine axis and an important regulator of an "angiogenic switch" that is essential for tumor and metastatic growth.

PET and PET/CT using 18F-FDG in the diagnosis and management of cancer patients

Positron emission tomography (PET) using 2-(18)F-fluoro-2-deoxy-D-glucose (FDG), a radioactive derivative of glucose, is an advanced imaging tool, based on the increased glucose consumption of cancer cells. FDG-PET provides information that is not obtainable with other imaging modalities, and is very effective in the diagnosis and management of patients with various types of cancers. However, there are some limitations, such as low FDG uptake in some cancers, substantial FDG uptake in inflammatory cells, and the lack of anatomical information and poor imaging quality of PET. A recently developed integrated PET/computed tomography (CT) system, which combines a PET camera and CT scanner in a single session, has overcome these drawbacks by providing both anatomical and functional imaging at the same position. PET and/or PET/CT using FDG is clinically useful in the detection of cancer, the differentiation of malignant and benign lesions, the staging of cancer before therapy, and the assessment of cancer therapy, as well as for determining the recurrence after therapy of most cancers, including lung cancer, gastrointestinal cancer, breast cancer, and malignant lymphoma. PET/CT has become the new standard approach to imaging in the diagnosis and management of many cancer patients.

PET/CT Imaging of Lung Cancer

Fluoro-deoxyglucose positron emission tomography (PET) imaging has a diagnostic and prognostic value in the initial staging, restaging, and surveillance of non-small-cell lung cancer (NSCLC). When used in conjunction with conventional radiologic imaging, PET imaging has been shown to result in significant changes in clinical management of NSCLC. Specifically, baseline PET imaging can improve initial staging and guide surgical and radiotherapy planning, whereas repeat PET imaging after the initiation of chemoradiotherapy can predict tumor response and help tailor therapy. After the end of definitive treatment, PET has greater diagnostic accuracy than other imaging modalities for the detection of tumor recurrence. The recent development of fused PET/CT imaging has improved the radiologic evaluation of NSCLC patients by combining metabolic and anatomic imaging; however, this has resulted in more complexity in the image interpretation. It is important for the interpreting physician to understand the role PET/CT plays in the staging, assessment of treatment, and follow-up after therapy in the multidisciplinary management of patients with NSCLC.

The effect of race on invasive staging and surgery in non-small-cell lung cancer

PURPOSE

Black patients with early-stage non-small-cell lung cancer (NSCLC) have worse overall survival than white patients. Decreased likelihood of resection has been implicated. To isolate the effect of decision making from access to care, we used receipt of surgical staging as a proxy for access and willingness to undergo invasive procedures, and examined treatments and outcomes by race.

PATIENTS AND METHODS

We examined registry and claims data of Medicare-eligible patients with nonmetastatic NSCLC in areas monitored by the Surveillance, Epidemiology, and End Results program from 1991 to 2001. Patients who obtained invasive staging, defined as bronchoscopy, mediastinoscopy, or thoracoscopy, were included. Logistic regression and Cox modeling calculated the odds of having staging and surgery, and survival outcomes.

RESULTS

A total of 14,224 patients underwent staging, and 6,972 had surgery for lung cancer. Black patients were less likely to undergo staging (odds ratio [OR] = 0.75; 95% CI, 0.67 to 0.83), and once staged, were still less likely to have surgery than whites (OR = 0.55; 95% CI, 0.47 to 0.64). Survival for blacks and whites was equivalent after resection (hazard ratio = 1.02; P = .06). Staged black patients were less likely to receive a recommendation for surgery when it was not clearly contraindicated (67.0% v 71.4%; P < .05), and were more likely to decline surgery (3.4% v 2.0%; P < .05).

CONCLUSION

Black patients obtain surgery for lung cancer less often than whites, even after access to care has been demonstrated. They are more likely not to have surgery recommended, and more likely to refuse surgery. Additional research should focus on the physician-patient encounter as a potential source of racial disparities.

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.

Chemotherapeutic issues in the management of unresectable stage III non-small cell lung cancer

The standard of care in unresectable stage IIIA/B non-small cell lung cancer is combined-modality therapy using both chemotherapy and thoracic radiation therapy. Although there is general agreement on this principle, there remain many controversies regarding the optimal combined-modality approach in this patient population. Both induction and concurrent chemoradiotherapy strategies were initially tested, with both approaches improving survival in randomized phase III trials. Several trials have now been completed comparing sequential versus concurrent approaches. There appears to be a modest and consistent advantage to the concurrent approach at the risk of an increase in the rates of acute toxicities, particularly esophagitis and myelosuppression. The concurrent approach used in the phase III trials evaluating the question of sequence has been the use of full-dose systemic chemotherapy rather than a low-dose radio-enhancing strategy. These approaches are distinctly different, and one must recognize this difference when evaluating results from clinical trials. A number of clinical trials have established the use of both induction and consolidation chemotherapy; however, the optimal approach remains unclear. What is clear is that this population of patients needs aggressive therapy directed at achieving locoregional control as well as control of occult micrometastatic disease that is present in the majority of cases. As treatment strategies have become more aggressive, survival outcomes have improved, although the differences have been modest at best, and the risk of severe toxicity has increased. Future aggressive approaches must enhance both locoregional and distant control of occult disease, with acceptable rates of both acute and long-term toxicities.

Functional Imaging in Lung Cancer

Accurate detection of the presence and extent of disease is vital in the management of non–small-cell lung cancer. While computed tomography and magnetic resonance imaging tend to be the routine diagnostic modalities used in the management of lung cancer, there have been significant advances in the field of functional and molecular imaging. In this article, we review the performance of the functional imaging techniques that are currently available for the evaluation of non–small-cell lung cancer. The techniques range from evaluation of glucose metabolism in tumors with fluorodeoxyglucose, to evaluation of proliferation with fluorothymidine and evaluation of tumor hypoxia with agents such as fluoromisonidazole. Magnetic resonance imaging with an emphasis on dynamic contrast enhancement of tumors as well as detecting of malignant lymph nodes with targeted contrast agents is discussed. Emerging technologies such as lung imaging fluorescence endoscopy are considered. The role of functional imaging in planning, predicting response to, and evaluating effects of, various therapies is explored.

Clinical Evaluation and Staging of Patients Who Have Lung Cancer

This article updates the performance characteristics of the most commonly used diagnostic and staging modalities in the evaluation of a patient who has lung cancer. Recent data with newer modalities, like positron emission tomography, are reviewed, and their role in this evaluation is discussed.

Seeking a home for a PET, part 3: Emerging applications of positron emission tomography imaging in the management of patients with lung cancer

Positron emission tomography (PET) imaging is an important tool to refine the diagnosis and staging approach in patients with a possible lung cancer. In addition, other applications of PET imaging are being explored. Data consistently show that the intensity of uptake on a PET scan correlates with the biological aggressiveness of a tumor. PET imaging for restaging after induction therapy does not appear to be accurate enough to guide management. The results of PET imaging late after completion of treatment are highly predictive of future survival, and changes in PET images after only one cycle of chemotherapy are predictive of how a patient will respond to that planned treatment. PET imaging may allow radiotherapy treatment fields to be planned with greater accuracy, although data on how this affects patient outcomes are not yet available. Further technologic improvements in PET scanners are likely to bring further benefits to the management of patients with lung cancer in the future.

Clinical Decisions Associated With Positron Emission Tomography in a Prospective Cohort of Patients With Suspected or Known Cancer at One United States Center

Purpose

In 2001, Medicare approved reimbursement of F-18 fluorodeoxyglucose positron emission tomography (PET) for a variety of cancers. PET has been observed to be more accurate than other imaging in cancer patients, but the impact of PET on management in routine practice is uncertain.

Patients and Methods

We studied a prospective cohort having noninvestigational PET at one university center. Before and after PET, a questionnaire was administered to solicit information regarding each physician's preceding actions, intended management, and probability estimates.

Results

Seventy-one physicians provided data on 248 patients, of whom 40% had new or suspected cancer and 60% were undergoing restaging or had suspected recurrence. Lung, lymphoma, and head/neck cancers accounted for two thirds of cases. Sixteen physicians made 64% of requests. Physicians changed their intended management in 61% of patients (95% CI, 54% to 66%). For individual physicians ordering at least 10 scans, the average kappa was 0.16 (range, −0.04 to 0.36), reflecting only slight level of agreement between their before and after PET plan. PET was associated with a change in 90 (79%) of 114 patients if the pre-PET intended plan involved more testing or biopsy. In 32% of cases, physicians changed to a treatment from a nontreatment strategy. The therapeutic goal and mode changed in 22 (7%) and 21 cases (8%), respectively.

Conclusion

This study confirms that physicians often change their decision making based on PET. This impact is likely due to combined effects of PET's improved accuracy and reduced physician uncertainty. Physicians may also be overconfident in interpreting PET and use it as the final arbiter after an extensive evaluation in lieu of tissue biopsy.

Seeking a home for a PET, part 1: Defining the appropriate place for positron emission tomography imaging in the diagnosis of pulmonary nodules or masses

There is a growing experience with positron emission tomography (PET) in patients with pulmonary nodules or masses. As PET imaging becomes more widely available, it is important to thoughtfully define when application of this technology is warranted. Review of the literature to date suggests that PET imaging for diagnosis of pulmonary lesions is most useful in patients who have a low or intermediate risk of lung cancer as determined by an evaluation of symptoms, risk factors, and radiographic appearance. There is little role for PET in diagnosis in patients with a very low or a high risk of lung cancer, and there is little role in patients with lesions < 1 cm in diameter, or lesions suspected to be an infection, a bronchioloalveolar carcinoma, or a typical carcinoid tumor.