[Meta-analysis of the efficacy of positron emission tomography with F-18-fluorodeoxyglucose in lung tumors. Basis for discussion of the German Consensus Conference on PET in Oncology 2000]

[Positron emission tomography in oncology]

Positron emission tomography (PET) is a highly sensitive imaging tool that noninvasively characterizes metabolic processes and molecular targets. PET has become an integral part of oncological diagnostics and an increasingly important tool for oncological therapy management. PET assessment, for example, directly influences treatment escalation or de-escalation in context of Hodgkin lymphomas or is, in case of lung cancer, able to reduce unnecessary surgeries. Hence, molecular PET imaging represents an indispensable tool in the development of personalized treatments. Furthermore, the development of new radiotracers for specific cell surface structures offers a promising potential for diagnostics and-combined with therapeutic nuclides-also for therapies. One recent example are radioligands targeting prostate-specific membrane antigen, which are relevant in prostate cancer.

Next-Generation Lung Cancer Surgery: A Brief Trip into the Future of the Research

Lung cancer is the third most frequent cancer and the leading cause of cancer-related mortality worldwide [...].

[Bronchial carcinoma: metastatic pathways with involvement of hilar and mediastinal lymph nodes]

SIGNIFICANCE OF LUNG CANCER

Lung cancer has enormous socioeconomical impact on our society due to its high prevalence and mortality. About 59,700 new cases of lung cancer were forecasted for 2022.

TNM SCHEME FOR STAGING

Correct staging is the basis for therapy planning, prognosis estimation, and future analyses. Staging is performed using the TNM scheme from the Union for International Cancer Control (UICC). Involvement of lymph nodes is used to differentiate between stage IIB and IIIC.

LYMPH NODE LEVELS FOR LUNG CANCER

Knowledge of the intrathoracic lymph node levels is crucial for the exact classification and its involvement has direct implications on therapy. The International Association for the Study of Lung Cancer (IASLC) proposed a unified lymph node map with exact anatomic definitions, which is recommended by the German national lung cancer guideline. The extent of lymph node involvement is stratified into N0-N3. Different metastatic paths are known depending on the location of the primary tumor, but the burden of disease has a greater influence on survival, than the location of metastases.

ASSESSING THE SPREAD OF LUNG CANCER

Computed tomography can assess operability of the primary tumor safely in most cases. Invasive procedures to confirm the diagnosis by sampling tissue should be performed after noninvasive diagnostics.

PRACTICAL RECOMMENDATION

Systematic lymph node dissection for all patients with non-small cell lung cancer intended for curative resection is recommended in the current German national guideline for lung cancer.

Multidisciplinary Postoperative Validation of 18F-FDG PET/CT Scan in Nodal Staging of Resected Non-Small Cell Lung Cancer

BACKGROUND

The aim of this study was to examine the validity of PET/CT scans in the preoperative identification of lymph node metastases (LNM) and compare them with postoperative outcomes.

METHODS

In this retrospective study, we included 87 patients with a solitary lung nodule or biopsy-proven non-small cell lung cancer treated in our institution from 2009 to 2015. Patients were divided into two groups and four subgroups, depending on pre- and postoperative findings.

RESULTS

According to our analysis, PET/CT scan has a sensitivity of 50%, a specificity of 88.89%, a positive predictive value of 63.16%, and a negative predictive value of 82.35%. Among the patients, 13.8% were downstaged in PET-CT, while 8% were upstaged. In 78.2% of cases, the PET/CT evaluation was consistent with the histology. Metastases without extracapsular invasion were seldom recognized on PET/CT.

CONCLUSIONS

This analysis showed the significance of extracapsular tumor invasion, which causes an inflammatory reaction, on LNM, which is probably responsible for preoperative false-positive findings. In conclusion, PET/CT scans are very effective in identifying patients without tumors. Furthermore, it is highly probable that patients with negative findings are free of disease.

Management of Early-Stage Resected Non-Small Cell Lung Cancer: Consensus Statement of the Lung cancer Consortium

BACKGROUND

Management of early-stage non-small cell lung cancer (ES-NSCLC) has evolved over the last few years especially in terms of work-up and the use of systemic therapy. This consensus statement was developed to present updated guidelines for the management of this disease.

METHODS

Multidisciplinary team (MDT) of lung cancer experts convened to discuss a set of pertinent questions with importance relevance to the management of ES-NSCLC. ES-NSCLC includes stages I, II and resected stage III. The experts included consultants in chest imaging, thoracic surgery, radiation oncology, and medical oncology. Questions were discussed in virtual meetings and then a written manuscript with supporting evidence was drafted, reviewed, and approved by the team members.

RESULTS

The Consensus Statement included 9 questions addressing work-up and management of ES-NSCLC. Background information and literature review were presented for each question followed by specific recommendations to address the questions by oncology providers. The Statement was endorsed by various oncology societies in the Gulf region.

CONCLUSION

The Consensus Statement serves as a guide for thoracic MDT members in the management of ES-NSCLC. Adaptation of these to the local setting is dictated usually by available resources and expertise, however, all efforts should be excreted to provide the optimal care to all patients whenever possible.

Clinical Applications of Artificial Intelligence in Positron Emission Tomography of Lung Cancer

The ability of a computer to perform tasks normally requiring human intelligence or artificial intelligence (AI) is not new. However, until recently, practical applications in medical imaging were limited, especially in the clinic. With advances in theory, microelectronic circuits, and computer architecture as well as our ability to acquire and access large amounts of data, AI is becoming increasingly ubiquitous in medical imaging. Of particular interest to our community, radiomics tries to identify imaging features of specific pathology that can represent, for example, the texture or shape of a region in the image. This is conducted based on a review of mathematical patterns and pattern combinations. The difficulty is often finding sufficient data to span the spectrum of disease heterogeneity because many features change with pathology as well as over time and, among other issues, data acquisition is expensive. Although we are currently in the early days of the practical application of AI to medical imaging, research is ongoing to integrate imaging, molecular pathobiology, genetic make-up, and clinical manifestations to classify patients into subgroups for the purpose of precision medicine, or in other words, predicting a priori treatment response and outcome. Lung cancer is a functionally and morphologically heterogeneous disease. Positron emission tomography (PET) is an imaging technique with an important role in the precision medicine of patients with lung cancer that helps predict early response to therapy and guides the selection of appropriate treatment. Although still in its infancy, early results suggest that the use of AI in PET of lung cancer has promise for the detection, segmentation, and characterization of disease as well as for outcome prediction.

Update on Molecular Imaging and Precision Medicine in Lung Cancer

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

ICORG 06-35: a prospective evaluation of PET-CT scan in patients with non-operable or non-resectable non-small cell lung cancer treated by radical 3-dimensional conformal radiation therapy: a phase II study

BACKGROUND

Radiotherapy (RT) is a key treatment modality in the curative treatment of patients with non-small cell lung cancer (NSCLC). Incorrect definition of the gross, or clinical, target volume is a common source of error which can lead to a reduced probability of tumour control.

OBJECTIVE

This was a pilot and a phase II study. The pilot evaluated the technical feasibility of integrating positron emission tomography-computed tomography (PET-CT) fusion. The primary outcome of the phase II study was to evaluate the safety of PET-CT scan-based RT by evaluating the rate of loco-regional recurrence outside the PET-CT planning target volume (PTV) but within conventional 3-D PTV.

METHODS

Patients underwent standard post-treatment follow-up, including repeated three monthly CT scans of the thorax. In case of loco-regional recurrence, three categories were considered, with only extra-PET scan PTV and intra-CT scan PTV recurrences considered as a failure. Our hypothesis was that the rate of these events would be < 10%.

RESULTS

Twelve patients were recruited; the study closed early due to poor recruitment. The primary endpoint of the pilot was met; it was feasible to deliver a PET-CT-based plan to ≥ 60% of patients. Two patients had intra-PET scan PTV recurrences, six had extra-PET scan PTV and extra-CT, and three patients had both. Another patient had extra-PET scan PTV and extra-CT as well as extra-PET scan PTV and intra-CT scan PTV recurrence.

CONCLUSION/ADVANCES IN KNOWLEDGE

PET-based planning has the potential to reduce radiation treatment volumes because of the avoidance of mediastinal lymph nodes that are PET negative.

Screening and Biosensor-Based Approaches for Lung Cancer Detection

Early diagnosis of lung cancer helps to reduce the cancer death rate significantly. Over the years, investigators worldwide have extensively investigated many screening modalities for lung cancer detection, including computerized tomography, chest X-ray, positron emission tomography, sputum cytology, magnetic resonance imaging and biopsy. However, these techniques are not suitable for patients with other pathologies. Developing a rapid and sensitive technique for early diagnosis of lung cancer is urgently needed. Biosensor-based techniques have been recently recommended as a rapid and cost-effective tool for early diagnosis of lung tumor markers. This paper reviews the recent development in screening and biosensor-based techniques for early lung cancer detection.

Molecular Imaging and Precision Medicine in Lung Cancer

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

[Positron emission tomography and stereotactic body radiation therapy for lung cancer: From treatment planning to response evaluation]

Stereotactic body radiation therapy is the standard treatment for inoperable patients with early-stage lung cancer. Local control rates range from 80 to 90 % 2 years after treatment. The role of positron emission tomography in patient selection is well known, but its use for target definition or therapeutic response evaluation is less clear. We reviewed the literature in order to assess the current state of knowledge in this area.

Staging of lung cancer: the role of noninvasive, minimally invasive and invasive techniques

Accurate staging and restaging of primary tumour and mediastinal nodes in patients with lung cancer is of significant importance. For primary tumours, computed tomography (CT) scans of the chest are recommended. Positron emission tomography (PET) imaging should be used in patients with curative intent treatment to evaluate metastatic disease. Diagnosis of the primary tumour should be performed using bronchoscopy or CT-guided transthoracic needle aspiration. In patients with enlarged mediastinal nodes and no distant metastasis, invasive staging of the mediastinum is required. For suspicious N2 or N3 disease, endoscopic needle techniques, such as endobronchial ultrasound and transbronchial needle aspiration, oesophageal ultrasound and fine needle aspiration, or a combination of both, are preferred to any surgical staging technique. In cases of suspicious nodes and negative results using needle aspiration techniques, invasive surgical staging using mediastinoscopy or video-assisted thoracic surgery should be performed. In central tumours or N1 nodes, preoperative invasive staging is indicated.Restaging after induction therapy remains a controversial topic. Today, neither CT, PET nor PET/CT scans are accurate enough to make final further therapeutic decisions for mediastinal nodal involvement. An invasive technique providing cytohistological information is still recommended.

Lung cancer

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

Role of imaging in diagnosis, staging and follow-up of lung cancer

PURPOSE OF REVIEW

Primary lung cancer is still the number one cause of cancer death worldwide. Screening, detection and staging of lung cancer are important because the only potentially curative therapy today is surgical resection of early-stage lung cancer.

RECENT FINDINGS

Different imaging techniques can be used in these different processes. Recent advances in computed tomography (CT) technology have allowed investigation of novel methods for the evaluation of lung cancer. Recent advances in magnetic resonance technology and administration of contrast media have further improved the image quality and diagnostic capability of magnetic resonance. Positron emission tomography (PET)/CT has been shown to be superior to stand-alone PET or CT in the evaluation of lymph nodes and in the detection of distant metastases.

SUMMARY

The current recommended imaging required for lung cancer staging is CT of the thorax and PET/CT from skull base to mid-thigh. However, with the recent developments in the armamentarium of imaging techniques, the choice of one of these techniques can be directed by the presence of a technique in a local hospital and/or by the presence of an experienced person at that time.

Modern diagnostic and therapeutic interventional radiology in lung cancer

Imaging has an important role in the multidisciplinary management of primary lung cancer. This article reviews the current state-of-the-art imaging modalities used for the evaluation, staging and post-treatment follow-up and surveillance of lung cancers, and image-guided percutaneous techniques for biopsy to confirm the diagnosis and for local therapy in non-surgical candidates.

Neural networks for nodal staging of non-small cell lung cancer with FDG PET and CT: importance of combining uptake values and sizes of nodes and primary tumor

PURPOSE

To evaluate the effect of adding lymph node size to three previously explored artificial neural network (ANN) input parameters (primary tumor maximum standardized uptake value or tumor uptake, tumor size, and nodal uptake at N1, N2, and N3 stations) in the structure of the ANN. The goal was to allow the resulting ANN structure to relate lymph node uptake for size to primary tumor uptake for size in the determination of the status of nodes as human readers do.

MATERIALS AND METHODS

This prospective study was approved by the institutional review board, and informed consent was obtained from all participants. The authors developed a back-propagation ANN with one hidden layer and eight processing units. The data set used to train the network included node and tumor size and uptake from 133 patients with non-small cell lung cancer with surgically proved N status. Statistical analysis was performed with the paired t test.

RESULTS

The ANN correctly predicted the N stage in 99.2% of cases, compared with 72.4% for the expert reader (P < .001). In categorization of N0 and N1 versus N2 and N3 disease, the ANN performed with 99.2% accuracy versus 92.2% for the expert reader (P < .001).

CONCLUSION

The ANN is 99.2% accurate in predicting surgical-pathologic nodal status with use of four fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT)-derived parameters. Malignant and benign inflammatory lymph nodes have overlapping appearances at FDG PET/CT but can be differentiated by ANNs when the crucial input of node size is used.

Impact of 18F-FDG PET/CT in the treatment of patients with non-small cell lung cancer

INTRODUCTION

Disease stage is the most important prognostic factor in lung cancer, and optimal staging is important to determine the best therapeutic option. FDG-PET/CT has demonstrated its value in early stage non-small cell lung cancer (NSCLC) but there is still insufficient data to define its role in other stages.

HYPOTHESIS

Information provided by FDG-PET/CT has an impact on the therapeutic management of patients with NSCLC.

METHODS

A retrospective review was made of patients who underwent FDG-PET/CT between January 2008 and December 2010 for the diagnosis of NSCLC. Clinical stage before and after FDG-PET/CT and information about any change in therapeutic decision due to information provided by FDG-PET/CT were collected. Using pathologic evaluation as the gold standard, sensitivity, specificity, and positive and negative predictive values for CT and FDG-PET/CT were calculated.

RESULTS

Of the 522 patients diagnosed of NSCLC, FDG-PET/CT was performed in 246 (47.1%). In 85 cases (34.6%) FDG-PET/CT led to stage migration. Treatment was modified in 60 patients (24.4% of all FDG-PET/CT performed), avoiding a futile thoracotomy in 13 cases (5.2%), and allowing treatment with curative intent in 26 (10.5%). Out of 90 patients (36.5%) evaluated as stage iii by CT staging, FDG-PET/CT modified the therapeutic approach in 36 (40%). For the 133 cases (54%) with pathological assessment of the mediastinal lymph nodes, sensitivity, specificity, positive predictive value and negative predictive value were 0.57, 0.64, 0.48 and 0.72 for CT, and 0.68, 0.86, 0.75 and 0.81 for FDG-PET/CT.

DISCUSSION

Our data support previous reports that FDG-PET/CT is essential in the staging process not only for patients with potentially operable NSCLC but also for stage iii patients, as demonstrated by our data.

Characteristics of Metastatic Mediastinal Lymph Nodes of Non-Small Cell Lung Cancer on Preoperative F-18 FDG PET/CT

PURPOSE

The aim of this study was to evaluate the characteristics of PET and CT features of mediastinal metastatic lymph nodes on F-18 FDG PET/CT and to determine the diagnostic criteria in nodal staging of non-small cell lung cancer.

METHODS

One hundred four non-small cell lung cancer patients who had preoperative F-18 FDG PET/CT were included. For quantitative analysis, the maximum SUV of the primary tumor, maximum SUV of the lymph nodes (SUVmax), size of the lymph nodes, and average Hounsfield units (aHUs) and maximum Hounsfield units (mHUs) of the lymph nodes were measured. The SUVmax, SUV ratio of the lymph node to blood pool (LN SUV/blood pool SUV), SUV ratio of the lymph node to primary tumor (LN SUV/primary tumor SUV), size, aHU, and mHU were compared between the benign and malignant lymph nodes.

RESULTS

Among 372 dissected lymph node stations that were pathologically diagnosed after surgery, 49 node stations were malignant and 323 node stations benign. SUVmax, LN SUV/blood pool SUV, and size were significantly different between the malignant and benign lymph node stations (P < 0.0001). However, there was no significant difference in LN SUV/primary tumor SUV (P = 0.18), mHU (P = 0.42), and aHU (P = 0.98). Using receiver-operating characteristic curve analyses, there was no significant difference among these three variables (SUVmax, LN SUV/blood pool SUV, and size). The optimal cutoff values were 2.9 for SUVmax, 1.4 for LN SUV/blood pool SUV, and 5 mm for size. When the cutoff value of SUVmax ≥2.9 and size ≥5 mm were used in combination, the positive predictive value was 44.2 %, and the negative predictive value was 90.9 %. When we evaluated the results based on the histology of the primary tumor, the negative predictive value was 92.3 % in adenocarcinoma (cutoff values of SUVmax ≥2.3 and size ≥5 mm) and 97.2 % in squamous cell carcinoma (cutoff values of SUVmax ≥3.6 and size ≥8 mm), separately.

CONCLUSIONS

In the lymph node staging of non-small cell lung cancer, SUVmax, LN SUV/blood pool SUV, and size show statistically significant differences between malignant and benign lymph nodes. These variables can be used to differentiate malignant from benign lymph nodes. The combination of the SUVmax and size of lymph node might have a good negative predictive value.

Use of PET/CT for patient selection and radiation therapy target volume definition in patients with non-small-cell lung cancer

SUMMARY PET scanning is having an increasing impact on the treatment of non-small-cell lung cancer with radiation therapy (RT) and chemoRT. It has a powerful impact on staging, often revealing evidence of more advanced, frequently incurable, disease in patients who would otherwise be considered suitable for treatment with potentially curative definitive RT. Approximately a third of curative RT candidates are found to be unsuitable for this often highly toxic form of treatment after PET, thereby ensuring that this intensive treatment is only given to those patients who might benefit from it. If a patient remains suitable for treatment with RT after PET staging, PET can play a further critical role in the targeting of the RT. Without the use of PET in this way, a quarter of patients or more would experience geographic misses, in which some tumor regions would be either underdosed or excluded entirely from treatment, thereby compromising the chances of a successful outcome. There is emerging evidence that the overall results of treatment with RT can be improved by the appropriate use of PET in non-small-cell lung cancer.

Stage IV lung cancer: Is cure possible?

Reporting a case, 53 years old male with stage IV Nonsamall cell lung cancer in view of cytologically proven malignant pleural effusion. Usually the management of stage IV lung cancer is with palliative intent where the patient receives palliative chemotherapy along with palliative radiotherapy and surgery if required. Most of the data on curative management of oligometastatic non-small cell lung cancer includes patient with adrenal metastasis and some reports with brain metastasis. There is scarce literature on the surgical management of stage IV lung cancer with pleural effusion.

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

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

Role of FDG-PET scans in staging, response assessment, and follow-up care for non-small cell lung cancer

The integral role of positron-emission tomography (PET) using the glucose analog tracer fluorine-18 fluorodeoxyglucose (FDG) in the staging of non-small cell lung cancer (NSCLC) is well established. Evidence is emerging for the role of PET in response assessment to neoadjuvant therapy, combined-modality therapy, and early detection of recurrence. Here, we review the current literature on these aspects of PET in the management of NSCLC. FDG-PET, particularly integrated (18)F-FDG-PET/CT, scans have become a standard test in the staging of local tumor extent, mediastinal lymph node involvement, and distant metastatic disease in NSCLC. (18)F-FDG-PET sensitivity is generally superior to computed tomography (CT) scans alone. Local tumor extent and T stage can be more accurately determined with FDG-PET in certain cases, especially in areas of post-obstructive atelectasis or low CT density variation. FDG-PET sensitivity is decreased in tumors <1 cm, at least in part due to respiratory motion. False-negative results can occur in areas of low tumor burden, e.g., small lymph nodes or ground-glass opacities. (18)F-FDG-PET-CT nodal staging is more accurate than CT alone, as hilar and mediastinal involvement is often detected first on (18)F-FDG-PET scan when CT criteria for malignant involvement are not met. (18)F-FDG-PET scans have widely replaced bone scintography for assessing distant metastases, except for the brain, which still warrants dedicated brain imaging. (18)F-FDG uptake has also been shown to vary between histologies, with adenocarcinomas generally being less FDG avid than squamous cell carcinomas. (18)F-FDG-PET scans are useful to detect recurrences, but are currently not recommended for routine follow-up. Typically, patients are followed with chest CT scans every 3-6 months, using (18)F-FDG-PET to evaluate equivocal CT findings. As high (18)F-FDG uptake can occur in infectious, inflammatory, and other non-neoplastic conditions, (18)F-FDG-PET-positive findings require pathological confirmation in most cases. There is increased interest in the prognostic and predictive role of FDG-PET scans. Studies show that absence of metabolic response to neoadjuvant therapy correlates with poor pathologic response, and a favorable (18)F-FDG-PET response appears to be associated with improved survival. Further work is underway to identify subsets of patients that might benefit individualized management based on FDG-PET.

Pituitary FDG uptake in a patient of lung cancer with bilateral adrenal metastases causing adrenal cortical insufficiency

A 64-year-old woman with history of lung cancer and left adrenal gland metastasis was referred for FDG PET/CT to assess the response to target therapy and local radiotherapy treatment. In addition to bilateral adrenal gland FDG uptake lesions, the PET/CT also showed focal FDG uptake in pituitary gland with standardized uptake value of 3.9. Adrenocorticotropic hormone serum level was 439 pg/mL (normal <46 pg/mL), and serum cortisol level was 6 μg/dL (normal range, 5-25 μg/dL). The image and serum test results suggested the diagnosis of lung cancer, with bilateral adrenal metastases causing adrenal cortical insufficiency with secondary pituitary gland hyperplasia.

Surgical treatment of oligometastatic non-small cell lung cancer

Patients with stage IV metastatic non-small cell lung cancer (NSCLC) are generally believed to have an incurable disease. Patients with oligometastatic disease represent a distinct subset of patients among those with metastatic disease. There is evidence that these patients have synchronous or metachronous satellite nodules in different pulmonary lobes or have solitary extrapulmonary metastases. In these cases, evidence has shown that surgical resection may provide patients with survival benefit. This article discusses the biology of the oligometastatic state in patients with lung cancer and the selection of patients for surgery, as well as the prognostic factors that influence survival of the patient. To properly select patients for an aggressive local treatment regime, accurate clinical staging is of prime importance. The use of FDG-PET should be considered for restaging if oligometastatic disease is suspected based on a patient's CT scan. A limitation of retrospective clinical studies for oligometastatic disease is that it is difficult to summarize and evaluate the available evidence for the effectiveness of surgical resection due to selection bias, and to a high degree of variability among different clinical studies. Nevertheless, we can certainly learn from the clinical experience acquired from retrospective case series to identify prognostic factors. Following surgical resection, the overall 5-year actuarial survival rate is about 28% for patients with satellite nodules and 21% for patients with ipsilateral nodules. Patients with resected brain metastasis achieve 5-year survival rates between 11% and 30%, and those with adrenalectomy for adrenal metastasis achieve 5-year survival rates of 26%.

PET and PET-CT of lung cancer

Accurate staging is essential to offer the patient the most effective available treatment and the best estimate of prognosis. In non-small cell lung cancer (NSCLC), surgical resection offers the best chance of cure in the early stages, either alone or in combination with chemo- or radiotherapy at the more advanced stages. However, many patients present with metastatic disease at the time of diagnosis. Both computed tomography (CT) and positron emission tomography (PET) using fluorodeoxyglucose (FDG) play an important role in the diagnosis and staging of lung cancer. CT provides excellent morphologic information but has significant limitations in differentiating between benign and malignant lesions either in an organ or in lymph nodes. FDG-PET is highly accurate in the detection of mediastinal lymph node metastases as well as extratharacic metastases. However, due to the poor anatomic information provided by PET, additional morphologic information is needed to properly locate a lesion. Imaging with PET integrated with computed tomography (PET/CT) offers essential advantages in comparison to PET alone, CT alone, or visual correlation of separate PET and CT. A combined PET/CT system provides PET and CT images perfectly coregistered so that lesions can be exactly localized.

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

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

Fluorodeoxyglucose uptake measured by positron emission tomography and standardized uptake value predicts long-term survival of CT screening detected lung cancer in heavy smokers

BACKGROUND

Fluorodeoxyglucose-positron emission tomography (FDG-PET) has proven its value in the diagnosis of undetermined pulmonary lesions, lung cancer staging, and assessment of prognosis. Purpose of this study is to clarify whether standardized uptake value (SUV) can predict clinical outcome of computed tomography (CT) screening detected lung cancer.

METHODS

We tested the predictive value of FDG-PET using SUV on long-term survival of 34 lung cancer patients, detected from 1035 heavy smokers > or = 50 years monitored by annual low-dose CT for 5 years, with a median follow-up of 75 months from diagnosis.

FINDINGS

PET scan was performed in 34 (89%) of 38 lung cancer patients diagnosed during the 5 years of screening and was positive in 32 (94%). Complete resection was achieved in 30 cases (88%), 20 (59%) were pathologic stage I and 23 (68%) were adenocarcinoma. Median SUV was 5.0 overall, being significantly lower in stage I (2.5 vs. 10.1, p = 0.001) and in adenocarcinoma (2.5 vs. 13.0, p = 0.001). The 5-year survival of lung cancer patients was 100% for SUV levels < or = 2.5, 60% for SUV more than 2.5 and less than 8, and only 20% for SUV > or = 8 (p = 0.001).

CONCLUSIONS

FDG-PET using SUV can predict long-term survival of screening detected lung cancer, in a noninvasive manner. Metabolic assessment of biologic behavior might improve the clinical management of CT-detected lung cancer and reduce the risk of unnecessary treatments for indolent disease.

[Comparison between PET(-FDG) and computed tomography in the staging of lung cancer. Consequences for operability in 94 patients]

INTRODUCTION

Lung cancer, a major application of FDG/PET-CT, has recently been introduced in daily practice in France. The authors retrospectively studied its impact on the management of this disease.

METHODS

The results of PET-CT and conventional assessment (brain imaging, chest and abdominal CT and possibly bone scintigraphy) were compared in 94 patients, referred for the staging of non-small cell lung cancer, or the assessment of a solitary lung lesion. The impact of thoracic lymph node involvement on the operability of patients was studied in 44 patients.

RESULTS

PET-CT revealed metastases in 20% of the patients without metastases found by conventional imaging and modified the stage of the disease in 28% of the cases. It changed the indication of surgical treatment in 19% of the cases and led to induction chemotherapy in two patients. In addition, two synchronous cancers were discovered. Regarding lymph node involvement, PET-CT remains of diagnostic value regardless of the scanner results.

CONCLUSION

The impact of PET-CT in assessing non-small cell lung cancer was confirmed in the authors' practice. Its interest and the consequences in some patients misclassified with conventional assessment have been demonstrated.

The impact of 18-fluorodeoxyglucose positron emission tomography on the staging, management and outcome of anal cancer

Accurate inguinal and pelvic nodal staging in anal cancer is important for the prognosis and planning of radiation fields. There is evidence for the role of 18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the staging and management of cancer, with early reports of an increasing role in outcome prognostication in a number of tumours. We aimed to determine the effect of FDG-PET on the nodal staging, radiotherapy planning and prognostication of patients with primary anal cancer. Sixty-one consecutive patients with anal cancer who were referred to a tertiary centre between August 1997 and November 2005 were staged with conventional imaging (CIm) (including computed tomography (CT), magnetic resonance imaging, endoscopic ultrasound and chest X-ray) and by FDG-PET. The stage determined by CIm and the proposed management plan were prospectively recorded and changes in stage and management as a result of FDG-PET assessed. Patients were treated with a uniform radiotherapy technique and dose. The accuracy of changes and prognostication of FDG-PET were validated by subsequent clinical follow-up. Kaplan–Meier survival analysis was used to estimate survival for the whole cohort and by FDG-PET and CIm stage. The tumour-stage group was changed in 23% (14 out of 61) as a result of FDG-PET (15% up-staged, 8% down-staged). Fourteen percent of T1 patients (3 out of 22), 42% of T2 patients (10 out of 24) and 40% of T3–4 patients (6 out of 15) assessed using CIm, had a change in their nodal or metastatic stage following FDG-PET. Sensitivity for nodal regional disease by FDG-PET and CIm was 89% and 62%, respectively. The staging FDG-PET scan altered management intent in 3% (2 out of 61) and radiotherapy fields in 13% (8 out of 61). The estimated 5-year overall survival (OS) and progression-free survival (PFS) for the cohort were 77.3% (95% confidence interval (CI): 55.3–90.4%) and 72.2% (95% CI: 51.5–86.4%), respectively. The estimated 5-year PFS for FDG-PET and CIm staged N2-3 disease was 70% (95% CI: 42.8–87.9%) and 55.3% (95% CI: 23.3–83.4%), respectively. FDG-PET shows increased sensitivity over CIm for staging nodal disease in anal cancer and changes treatment intent or radiotherapy prescription in a significant proportion of patients.

Positron Emission Tomography (PET) radiotracers in oncology--utility of 18F-Fluoro-deoxy-glucose (FDG)-PET in the management of patients with non-small-cell lung cancer (NSCLC)

PET (Positron Emission Tomography) is a nuclear medicine imaging method, frequently used in oncology during the last years. It is a non-invasive technique that provides quantitative in vivo assessment of physiological and biological phenomena. PET has found its application in common practice for the management of various cancers.Lung cancer is the most common cause of death for cancer in western countries.This review focuses on radiotracers used for PET scan with particular attention to Non Small Cell Lung Cancer diagnosis, staging, response to treatment and follow-up.

Diagnostic performance of (18)F-FDG PET/CT for lymph node staging in patients with operable non-small-cell lung cancer and inflammatory lung disease

As (18)F-fluorodeoxyglucose (FDG) is taken up by inflammatory lymph nodes, it could be falsely interpreted as metastasis. Therefore, we evaluated the diagnostic ability of positron emission tomography/computed tomography (PET/CT) for lymph node staging of lung cancer when inflammatory lung disease coexisted. Patients with operable non-small-cell lung cancer and FDG-avid lymph nodes were retrospectively classified into two groups; those with inflammatory lung disease (ILD) and those without it (NILD). Receiver operating characteristic (ROC) curve analysis was performed for maximum standardized uptake value (SUVmax), pattern of FDG uptake, maximum Hounsfield unit, and size, and then the areas under the ROC curves (AUCs) were compared between subgroups. There were 124 patients (ILD/NILD = 38/86) and 396 FDG-avid lymph nodes (ILD/NILD = 140/256). The average number of FDG-avid lymph nodes was greater in ILD (3.7 vs. 2.9, p = 0.039), whereas the proportion of metastasis was higher in NILD (25.4% vs. 11.4%, p = 0.002). With all N1-N3 lymph nodes and the NILD group, the AUC values of all four parameters were significantly greater than 0.5 (p < 0.05), and SUVmax was the most valuable parameter for lymph node metastasis. However, in the ILD group, only the AUC value of SUVmax was significantly greater than 0.5. These results were reproduced when analyses were performed with N1-N2 lymph nodes. In conclusion, SUVmax was the most valuable PET/CT parameter for assessment of lymph node metastasis in patients with operable non-small-cell lung cancer. In addition, it was the only valuable parameter when inflammatory lung disease coexisted.

Clinical impact of, and prognostic stratification by, F-18 FDG PET/CT in head and neck mucosal squamous cell carcinoma

BACKGROUND

The aim of this study was to determine prospectively the incremental value of positron emission tomography/computed tomography (PET/CT) over conventional assessment (clinical examination and CT/MRI imaging).

METHODS

All patients undergoing (18)F-fluorodeoxyglucose (FDG)-PET/CT for primary head and neck mucosal squamous cell carcinoma between January 2002 and December 2003 (inclusive) were included in this study provided they had undergone contemporaneous conventional assessment of the head and neck region and had 12 months minimum follow-up.

RESULTS

Seventy-six patients underwent 100 PET/CT scans. The majority of patients (74%) were treated with definitive (chemo)radiotherapy. Median follow-up time was 28 months. PET/CT led to a TNM classification alteration in 34% (12/35), a change in radiotherapy planning technique and/or dose in 29% (10/35), and altered treatment response assessment in 43% (13/30). A complete metabolic response was predictive of overall survival (p = .037).

CONCLUSION

Our results support incorporation of PET/CT into the management paradigm of head and neck mucosal squamous cell carcinoma.

Fluorine-18-alpha-methyltyrosine positron emission tomography for diagnosis and staging of lung cancer: a clinicopathologic study

PURPOSE

L-[3-(18)F]-alpha-methyltyrosine ([(18)F]FMT) is an amino acid tracer for positron emission tomography (PET). We evaluated the diagnostic usefulness of [(18)F]FMT PET in non-small-cell lung cancer (NSCLC) patients. Tumor uptake of [(18)F]FMT was compared with that of 2-[(18)F]-fluoro-2-deoxy-D-glucose ([(18)F]FDG) and correlated with L-type amino acid transporter 1 (LAT1) expression.

EXPERIMENTAL DESIGN

Fifty NSCLC patients were enrolled in this study, and a pair of PET study with [(18)F]FMT and [(18)F]FDG was done. LAT1 expression and Ki-67 labeling index of the resected tumors were analyzed by immunohistochemical staining.

RESULTS

For the primary tumor detection, [(18)F]FMT PET exhibited a sensitivity of 90% whereas the sensitivity for [(18)F]FDG PET was 94%. For lymph node staging, the sensitivity and specificity of [(18)F]FMT PET were 57.8% and 100%, and those of [(18)F]FDG PET were 65.7% and 91%, respectively. The expression of LAT1 in squamous cell carcinoma and large cell carcinoma was significantly higher than that in adenocarcinoma. [(18)F]FMT uptake was also higher in squamous cell carcinoma and large cell carcinoma than in adenocarcinoma. Uptake of [(18)F]FMT in the tumor is closely correlated with LAT1 expression (rho = 0.890).

CONCLUSION

[(18)F]FMT PET had no false-positives in the detection of primary tumor and lymph node metastasis and could improve the diagnostic performance in NSCLC. Uptake of [(18)F]FMT correlated with the expression of LAT1 that showed a significant association with cellular proliferation.