Comparison of whole-body FDG-PET to bone scan for detection of bone metastases in patients with a new diagnosis of lung cancer

Incidence of hypertrophic pulmonary osteoarthropathy associated with primary lung cancer

BACKGROUND AND OBJECTIVE

Although the association of hypertrophic pulmonary osteoarthropathy (HPO) with lung cancer was investigated in the 1960s, the recent incidence of clinically apparent HPO is not known. Data from a large series of patients with lung cancer were analysed, in order to assess the incidence of possible HPO, based on bone scintigraphy, as well as the incidence of clinically confirmed HPO. The clinical features of confirmed HPO were also evaluated.

METHODS

The medical records of patients admitted with lung cancer between January 1986 and August 2004 were reviewed. Bone scintigraphy showing symmetrical, abnormally high uptake in joints and/or long bones was considered to be suggestive of HPO. Patients who also had finger clubbing and joint pain were considered to have a confirmed diagnosis of HPO. Clinical histories and hormone levels were then investigated in these patients, to identify possible causal factors.

RESULTS

Among the 1226 lung cancer patients, 55 (4.5%) demonstrated abnormally high uptake on bone scintigraphy, suggesting possible HPO. Ten (0.8%) patients had clubbed fingers and joint pain and were eventually confirmed as having HPO. Serum hormone concentrations were abnormally high in the patients with confirmed HPO.

CONCLUSIONS

This retrospective study indicated that 4.5% of lung cancer patients showed findings suggestive of HPO, a frequency similar to that reported previously. However, patients with HPO rarely showed the complete triad of signs. Although increased hormone concentrations may have caused the HPO, further investigation is required to confirm this.

Small cell carcinoma originating from the cavernous sinus

BACKGROUND

We report a rare case of small cell carcinoma originating from the right cavernous sinus in a 55-year-old male. The patient had sudden onset of right abducens palsy following right oculomotor palsy.

METHODS

Post-contrast T1-weighted MRI revealed a mass lesion of 3-cm maximum size occupying the right cavernous sinus and extending to the right middle cranial fossa. After biopsy via the frontozygomatic approach, one radiosurgery treatment was followed by four cycles of chemotherapy (cisplatin together with VP-16 therapy), after which the lesion diminished dramatically in size.

RESULTS

Complete remission has currently been achieved. The patient recovered from the extraocular muscle paresis and returned to his previous work. Although it is considered possible that small cell carcinoma can occur wherever neuroendocrine cells exist, a lesion originating in the cranium is extremely rare. To the best of our knowledge, this is the first report of small cell carcinoma of intracranial origin.

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.

Detection of hematogenous bone metastasis in cervical cancer: 18F-fluorodeoxyglucose-positron emission tomography versus computed tomography and magnetic resonance imaging

BACKGROUND

In this large-scale, retrospective study, the authors evaluated the diagnostic performances of computed tomography (CT), magnetic resonance (MR) imaging, and (18)F-fluorodeoxyglucose-positron emission tomography ((18)F-FDG-PET) in detecting hematogenous bone metastasis in patients with cervical cancer. The associated risk factors also were analyzed.

METHODS

Patients with invasive cervical cancer who had both (18)F-FDG-PET studies and CT or MR imaging studies were selected. Patients who had either International Federation of Gynecology and Obstetrics (FIGO) stage III/IV disease or positive lymph node metastasis at the time of primary staging and patients who had suspected recurrent disease were included in the analyses. The diagnostic performances of PET was compared with the performance of CT and MR imaging by using the area under the receiver-operating-characteristic curve (AUC). Both univariate and multivariate analyses were applied to assess the risk factors for hematogenous bone metastasis at primary staging.

RESULTS

PET was more sensitive than CT (P = .004) and was more specific than MR imaging (P = .04). The diagnostic performance of PET was significantly superior to the performance CT (AUC, 0.964 vs 0.662; P < .001) and MR (AUC, 0.966 vs 0.833; P = .033). Both FIGO stage and the extent of lymph node metastases were associated with hematogenous bone metastasis in univariate analysis. However, the extent of lymph node metastases was the only significant risk factor in multivariate analysis (P = .025).

CONCLUSIONS

The current study demonstrated the superiority of (18)F-FDG-PET over CT and MR imaging for detecting hematogenous bone metastasis in patients with advanced cervical cancer. Hematogenous bone metastasis in cervical cancer was associated with the extent of lymph node metastases rather than with FIGO stage.

[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.

Detection of bone metastases in patients with lung cancer: 99mTc-MDP planar bone scintigraphy, 18F-fluoride PET or 18F-FDG PET/CT

PURPOSE

The aim of the study was to compare the diagnostic accuracy of (18)F-fluorodeoxyglucose (FDG) PET/CT versus standard planar bone scintigraphy (BS) and (18)F-labelled NaF ((18)F) PET for the detection of bone metastases (BM) in non-small cell lung cancer (NSCLC).

METHODS

(18)F-FDG PET/CT was performed in 126 patients with NSCLC. Within 7 days BS (n = 58) or (18)F PET (n = 68) was performed. (18)F-FDG PET/CT, BS and (18)F PET were evaluated by two experienced readers. Lesions were graded on a scale from 1 (definite BM) to 5 (degenerative lesion), and equivocal lesions were determined as indifferent (grade 3).

RESULTS

A total of 92 patients showed degenerative lesions (grade 4/5) on PET/CT, BS or (18)F PET. In 34 patients (27%) BM lesions were diagnosed (grades 1 and 2). In 13 of 18 patients BM were concordantly diagnosed with PET/CT and (18)F PET. PET/CT showed more BM compared to (18)F PET (53 vs 40). In one patient one osteolytic BM was false-negative on (18)F PET. However, (18)F PET identified four patients with BM compared to negative findings on PET/CT. Of 16 patients, 11 had concordant findings of BM on PET/CT and BS. In three patients BS was false-negative and in two patients BM were diagnosed as indifferent.

CONCLUSION

Integrated (18)F-FDG PET/CT is superior to BS in the detection of osteolytic BM in NSCLC. Thus, PET/CT may obviate the need to perform additional BS or (18)F PET in the staging of NSCLC, which significantly reduces costs.

The role of whole-body FDG PET/CT, Tc 99m MDP bone scintigraphy, and serum alkaline phosphatase in detecting bone metastasis in patients with newly diagnosed lung cancer

Bone scan (BS) and serum alkaline phosphatase (ALP) concentration are used to detect bone metastasis in malignancy, although whole-body fluoro-D-glucose positron emission tomography computed tomography (FDG PET/CT) is being used increasingly. But BS is still used for the detection of metastatic bone lesion. So we compared the usefulness of PET/CT, BS, and serum ALP in detecting bone metastases in patients with newly diagnosed lung cancer. The medical record database was queried to identify all patients with a new diagnosis of lung cancer between January 2004 and December 2005, who had a PET/CT, BS, and serum ALP before treatment. We retrospectively reviewed all patients' records and radiological reports. One hundred eighty-two patients met the inclusion criteria. Bone metastases were confirmed in 30 patients. The sensitivity values were 93.3% for PET/CT, 93.3% for BS, 26.7% for serum ALP concentration, and 26.7% for BS complemented with serum ALP concentration. The respective specificity values were 94.1%, 44.1%, 94.1%, and 97.3%. The kappa statistic suggested a poor agreement among the three modalities. FDG PET/CT and BS had similar sensitivity, but PET/CT had better specificity and accuracy than BS. PET/CT is more useful than BS for evaluating bone metastasis. However, in the advanced stage, because of its high specificity, BS complemented with serum ALP is a cost-effective modality to avoid having to use PET/CT.

False positive 18F-FDG-PET/CT in a patient after talc pleurodesis

A 61-year-old man presented with spontaneous pneumothorax. After diagnosis of emphysemic bullae, the patient underwent talc pleurodesis and had no further complaints. Five years later a routine chest X-ray showed suspicious pleural lesions in addition to the emphysema, which was deemed compatible with the known history of talc pleurodesis. Subsequent chest CT, however, revealed one lesion in the right lung that appeared not typical for this condition in addition to multiple lesions in pleural proximity. FDG-PET/CT demonstrated high glucose uptake in all the lesions. Subsequent needle biopsy of the suspicious intrapulmonary and also of one mediastinal lesion yielded the histopathological diagnosis of talcum granuloma with long-standing calculous fibrotic changes and no evidence of malignancy. This report on PET/CT after talc pleurodesis addresses the potential pitfalls caused by this condition, as chronic granulomatous reactions, like other inflammatory lesions, may account for highly increased FDG uptake which should be interpreted with caution and not simply read as a sign of malignancy. PET/CT offers the opportunity to exactly localize the areas of increased FDG uptake within regions of pleural thickening caused by talc deposition, however, the dilemma of misleading FDG accumulation cannot be solved by this hybrid imaging modality.

Whole-body magnetic resonance imaging and positron emission tomography-computed tomography in oncology

The advent of positron emission tomography-computed tomography (PET-CT) and whole-body magnetic resonance imaging (WB-MRI) has introduced tumor imaging with a systemic and functional approach compared with established sequential, multimodal diagnostic algorithms.Whole-body PET with [18F]-fluoro-2-desoxy-glucose is a useful imaging procedure for tumor staging and monitoring that can visualize active tumor tissue by detecting pathological glucose metabolism. The combination of PET with the detailed anatomical information of multislice computed tomography as dual-modality scanners has markedly increased lesion localization and diagnostic accuracy compared with both modalities as standalone applications.Hardware innovations, such as the introduction of multi-receiver channel whole-body MRI scanners at 1.5 and, recently, 3 T, combined with acquisition acceleration techniques, have made high-resolution WB-MRI clinically feasible. Now, a dedicated assessment of individual organs with various soft tissue contrast, spatial resolution, and contrast media dynamics can be combined with whole-body anatomical coverage in a multiplanar imaging approach. More flexible protocols (eg, T1-weighted turbo spin-echo and short inversion recovery imaging, dedicated lung imaging or dynamic contrast-enhanced studies of the abdomen) can be performed within 45 minutes.Whole-body magnetic resonance imaging has recently been proposed for tumor screening of asymptomatic individuals, and potentially life-changing diagnoses, such as formerly unknown malignancy, have been reported. However, larger patient cohort studies will have to show the cost efficiency and the clinical effectiveness of such an approach.For initial tumor staging, PET-CT has proved more accurate for the definition of T-stage and lymph node assessment, mainly because of the missing metabolic information in WB-MRI. However, new applications, such as magnetic resonance whole-body diffusion-weighted imaging or lymphotropic contrast agents, may significantly increase sensitivity in near future. Whole-body magnetic resonance imaging has shown advantages for the detection of distant metastatic disease, especially from tumors frequently spreading to the liver or brain and as a whole-body bone marrow screening application. Within this context, WB-MRI is highly accurate for the detection of skeletal metastases and staging of multiple myeloma. This article summarizes recent developments of CT/PET-CT and WB-MRI and highlights their performance within the scope of systemic oncological imaging.

Accuracy of Fluorodeoxyglucose-Positron Emission Tomography for Diagnosis of Single Bone Metastasis

PURPOSE

The aim of this study was to compare the accuracy of fluorodeoxyglucose-positron emission tomography (FDG-PET) with bone scan for diagnosis of single bone metastasis using a semiquantitative method.

MATERIAL AND METHODS

Seventy-six patients with suspected single bone metastasis, who underwent both FDG-PET and a bone scan, were selected. The number and location of lesions detected upon both FDG-PET and bone scan were recorded, and the lesions were compared using the McNemar test. For semiquantitative analysis, a maximum (max) standard uptake value (SUV) of 2.5 was used as the positive cutoff value for metastasis. The difference in max SUV value among 3 groups (osteolytic, osteoblastic, and benign lesions) was assessed using the Student-Newman-Keuls method. Biopsy results, other imaging findings (multirow detector computed tomography, magnetic resonance imaging), and the patient's clinical course were used as references.

RESULTS

There were 47 single bone metastases and 29 benign lesions. The sensitivity, specificity, and accuracy of bone scans for diagnosing bone metastases were 89%, 41%, and 71%, respectively, and those of FDG-PET were 85%, 52%, and 72%, respectively. These data were not significantly different (P > 0.05). Using a max SUV of 2.5 as the positive cutoff value for metastasis, the specificity and accuracy of FDG-PET, 83% for each, improved. When classifying bone metastasis as osteoblastic or osteolytic, the max SUV was significantly higher in osteolytic metastasis than in osteoblastic and benign lesions (P = 0.001).

CONCLUSIONS

Fluorodeoxyglucose-positron emission tomography (FDG-PET) using the semiquantitative parameter SUV improves the diagnostic ability to differentiate between single bone metastases and benign lesions.

Detection of bone metastases in thyroid cancer patients: bone scintigraphy or 18F-FDG PET?

BACKGROUND

Similar to the situation in other tumour types, it is currently unclear whether fluorodeoxyglucose (FDG) positron emission tomography (PET) is adequate in the detection of bone metastases of thyroid cancer. The purpose of this retrospective study was to evaluate the performance of bone scans in comparison with FDG PET in the detection of bone metastases in patients with differentiated thyroid cancer (DTC).

MATERIALS AND METHODS

Twenty-four patients had undergone both FDG PET and bone scans within 6 months because of suspected bone metastases. All scans were re-evaluated using all available additional imaging and clinical data for verification. Scan findings were scored as positive, negative or doubtful.

RESULTS

Bone metastases were present in eight of 24 (33%) patients. Only bone scintigraphy but not FDG PET suggested the presence of bone metastases in three patients, all confirmed with magnetic resonance imaging (MRI)/X-ray. Five patients were identified with bone metastases on both bone scan and FDG PET, which was confirmed by computed tomography (CT)/MRI/X-ray in four. Five patients had doubtful findings on bone scans whereas FDG PET scans were negative. MRI showed degenerative disorders in two of five and was normal in two. Eleven patients had both a negative bone scan and FDG PET scan.

CONCLUSION

In three of eight (38%) thyroid cancer patients bone metastases were only identified on bone scans. Therefore, bone scans are still valuable in detecting bone metastases in patients with DTC and can not be replaced by FDG PET.

Staging of Lung Cancer

Imaging techniques play a vital role in the diagnosis, staging, and follow-up of patients who have lung cancer. For this purpose, PET has become an important adjunct to conventional imaging techniques such as chest radiography, CT, ultrasonography, and MR imaging. The ability of PET to differentiate the metabolic properties of tissues allows more accurate assessment of undetermined lung lesions, mediastinal lymph nodes, or extrathoracic abnormalities, tumor response after induction treatment, and detection of disease recurrence.

Age-Related Changes in the Metabolic Activity and Distribution of the Red Marrow as Demonstrated by 2-Deoxy-2-[F-18]fluoro-d-glucose-Positron Emission Tomography

OBJECTIVES

The objective of the study was to determine age-related changes occurring in red marrow with regard to its distribution and the degree of its metabolic activity by whole-body 2-deoxy-2-[F-18]fluoro-D-glucose (FDG)-positron emission tomography (PET).

METHODS

This retrospective study included 112 patients (56 male, 56 female, mean age 40 years, range 2-85) who underwent whole-body FDG-PET scans for assessment of disorders that were determined not to affect red marrow activity. These patients were categorized into the following groups with equal gender distribution: 0-15 years (12 individuals), 16-25 years (20), 26-35 years (10), 36-45 years (20), 46-55 years (14), 56-65 years (16), 66-75 years (14), and 76-85 years (6). Whole-body FDG-PET images were performed at 60 min after the intravenous administration of 0.14 mCi/kg of FDG. By employing a dedicated whole-body PET scanner. Maximal standardized uptake value (SUV(max)) was calculated from three consecutive transverse sections of the upper thirds of the humeri and femora, manubrium of the sternum, 12th thoracic and 5th lumbar vertebra and anterior superior iliac crests of the pelvis. All available results from other imaging examinations [magnetic resonance imaging (MRI), computed tomography (CT), and conventional radiolography], laboratory data, biopsies, and the clinical course of these subjects were reviewed to make certain that the bone marrow sites examined were free of any known pathologies.

RESULTS

SUV(max) in the extremities showed significant decline with aging (correlation coefficient of -0.60 to -0.67, p < 0.01). In contrast, a weak correlation was noted in the axial skeletal activity with advancing age (correlation coefficient of -0.28 to -0.48, p < 0.05).

CONCLUSIONS

These data suggest that FDG metabolic activity of the red marrow in the extremities decline significantly with normal aging, while that of the axial skeleton show minimal decrease related to this biologic phenomenon. These findings are of value in assessing the effects of hematological and other disorders in the distribution and the metabolic activity of this important tissue and testing therapeutic interventions that are employed for treating such maladies.

Structural and functional imaging of normal bone marrow and evaluation of its age-related changes

A number of noninvasive imaging techniques have been used for the evaluation of bone marrow, including magnetic resonance imaging (MRI) and bone marrow scintigraphy. The appearance of bone marrow on MRI varies considerably depending on the proportion of red and yellow marrow, and the composition of the red marrow and its distribution with relation to age and sex. The composition of bone marrow also can vary under physiological and pathological conditions. MRI is a highly sensitive technique for evaluating the bone marrow, but it is limited in its practical use for whole-body bone marrow screening. Bone marrow scintigraphy with radiolabeled compounds such as technetium-99m-labeled nanocolloid and monoclonal antibodies has the advantage of evaluating the entire bone marrow, and has been used for the diagnosis of various bone marrow disorders. In addition, (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging can be used to evaluate bone marrow metabolism and disease and to provide information about the state of the primary tumor, lymph nodes, and distant metastases. Understanding of the appearance of normal bone marrow, including age- and sex-specific differences with each of these imaging modalities, is essential to permit accurate diagnosis of benign and malignant bone marrow disorders. We present a review of MRI and scintigraphy of normal bone marrow with some emphasis on FDG-PET imaging in assessing marrow activity in normal and abnormal states and also present preliminary data regarding normal age-related changes in bone marrow through use of FDG-PET, as well as the role of segmentation of bone marrow on MRI for quantitative calculation of the metabolic volumetric product for red marrow metabolism using FDG-PET.

Lung cancer: New surgical approaches

Over the past two decades, many surgical specialties have seen a dramatic shift from large, open operations with wide incisions towards more-minimal incisions and less-invasive procedures. Surgical techniques for lung cancer are no exception, and today, video-assisted thoracic surgical lobectomies are being performed with increasing frequency in large-volume thoracic practices. Despite these new surgical techniques, however, the most substantial innovations that have changed surgical outcomes occurred away from the operative theatre. In lung cancer, in particular, the last 20 years have witnessed the clinical debut of more sophisticated, more elegant and more accurate imaging modalities for improved screening, diagnostic and staging, such as the spiral CT scan, PET scan, PET/CT and the endobronchial ultrasound machine. This technology has been complimented by more targeted chemotherapeutic regimens, novel methods of administering more accurate and more concentrated doses of radiation therapy, and innovative local excisional methods, such as the Cyberknife and radiofrequency ablation. The result has been that surgical excision, although remaining the most effective local therapeutic modality in early-stage lung cancer, is no longer the 'lone ranger' treatment, but rather is part of a complex mosaic of multimodality therapy. As scientific advances continue to be translated into the clinic, this trend will inexorably continue with the advent of a molecular staging system using molecular markers and tumour profiling, which ultimately could enhance our ability to predict tumour chemosensitivity. In this brave new world, however, complete surgical resection of the lung cancer will continue to be critical.

Detection of bone metastases: assessment of integrated FDG PET/CT imaging

PURPOSE

To retrospectively evaluate the positive predictive value (PPV) of fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) in the identification of malignant bone lesions when the PET and CT findings are discordant and concordant.

MATERIALS AND METHODS

The study conformed to HIPAA standards, and the need for informed consent was waived by the institutional review board that approved the study. FDG PET/CT reports of 712 patients were reviewed to identify patients with malignant bone lesions. Fifty-nine patients (30 female and 29 male patients; age range, 10-82 years) with 113 lesions were analyzed. With use of confirmation from histopathologic examination or clinical follow-up, the PPVs of the integrated examination and of the stand-alone CT and PET components of the examination were calculated. The results were stratified according to cancer type, chemotherapy status, and number of bone lesions and were compared by using Fisher exact tests.

RESULTS

Of 47 lesions with positive findings at both PET and CT, 46 were malignant and one was benign, for a PPV of 98%. Of 31 lesions with positive findings at PET and negative findings at CT, 19 were malignant and 12 were benign, for a PPV of 61%. Of 35 lesions with negative findings at PET and positive findings at CT, six were malignant and 29 were benign, for a PPV of 17%. Independently, the PPV of all lesions with positive findings at PET was significantly higher than that of all lesions with positive findings at CT. Chemotherapy status for lesions with positive findings at CT and the number of lesions per patient had a statistically significant effect on the PPV of examinations (P = .02 and P < .001, respectively).

CONCLUSION

PET/CT has a very high PPV for bone metastases (98%) when the findings at PET and CT are concordant; however, in lesions with discordant PET and CT findings at the integrated examination, PPV is markedly diminished.

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

BACKGROUND

Small-cell lung cancer (SCLC) accounts for 15%-20% of all lung cancer cases. Accurate and fast staging is mandatory when choosing treatment, but current staging procedures are time consuming and lack sensitivity.

PATIENTS AND METHODS

A prospective study was designed to examine the role of combined positron emission tomography/computed tomography (PET/CT) compared with standard staging (CT, bone scintigraphy and immunocytochemical assessment of bone marrow biopsy) of patients with SCLC. Thirty-four consecutive patients were included. Twenty-nine patients received initial PET/CT.

RESULTS

PET/CT caused change of stage in 5/29 (17%). Excluding patients with unconfirmed findings or pleural effusion, the sensitivity for accurate staging of patients with extensive disease was the following: for standard staging 79%, PET 93% and PET/CT 93%. Specificity was 100%, 83% and 100%, respectively.

CONCLUSION

The results from this first study on PET/CT in SCLC indicates that PET/CT can simplify and perhaps even improve the accuracy of the current staging procedure in SCLC. A larger clinical trial, preferably with consequent histological confirmation in case of discordance, however, is warranted.

Physics and imaging for targeting of oligometastases

Oligometastases refer to metastases that are limited in number and location and are amenable to regional treatment. The majority of these metastases appear in the brain, lung, liver, and bone. Although the focus of interest in the past within radiation oncology has been on the treatment of intracranial metastases, there has been growing interest in extracranial sites such as the liver and lung. This is largely because of the rapid development of targeting techniques for oligometastases such as intensity-modulated and image-guided radiation therapy, which has made it possible to deliver single or a few fractions of high-dose radiation treatments, highly conformal to the target. The clinical decision to use radiation to treat oligometastases is based on both radiobiological and physics considerations. The radiobiological considerations involve improvement of treatment schema for time, dose, and volume. Areas of interests are hypofractionation, tumor and normal tissue tolerance, and hypoxia. The physics considerations for oligometastases treatment are focused mainly on ensuring treatment accuracy and precision. This article discusses the physics and imaging aspects involved in each step of the radiation treatment process for oligometastases, including target definition, treatment simulation, treatment planning, pretreatment target localization, radiation delivery, treatment verification, and treatment evaluation.

Screening for bone metastases: whole-body MRI using a 32-channel system versus dual-modality PET-CT

The diagnostic accuracy of screening for bone metastases was evaluated using whole-body magnetic resonance imaging (WB-MRI) compared with combined fluorodeoxyglucose (FDG) positron emission tomography (PET) and computed tomography (CT) (FDG-PET-CT). In a prospective, blinded study, 30 consecutive patients (18 female, 12 male; 24-76 years) with different oncological diseases and suspected skeletal metastases underwent FDG-PET-CT as well as WB-MRI with the use of parallel imaging (PAT). With a 32-channel scanner, coronal imaging of the entire body and sagittal imaging of the complete spine was performed using T1-weighted and short tau inversion recovery (STIR) sequences in combination. PET-CT was conducted using a low-dose CT for attenuation correction, a PET-emission scan and diagnostic contrast-enhanced CT scan covering the thorax, abdomen and pelvis. Two radiologists read the MRI scans, another radiologist in combination with a nuclear medicine physician read the PET-CT scans, each in consensus. The standard of reference was constituted by radiological follow-up within at least 6 months. In 28 patients, 102 malignant and 25 benign bone lesions were detected and confirmed. WB-MRI showed a sensitivity of 94% (96/102), PET-CT exams achieved 78% (79/102; P<0.001). Specificities were 76% (19/25) for WB-MRI and 80% (20/25) for PET-CT (P>0.05). Diagnostic accuracy was 91% (115/127) and 78% (99/127; P<0.001), respectively. Cut-off size for the detection of malignant bone lesions was 2 mm for WB-MRI and 5 mm for PET-CT. WB-MRI revealed ten additional bone metastases due to the larger field of view. In conclusion, WB-MRI and FDG-PET-CT are robust imaging modalities for a systemic screening for metastatic bone disease. PAT allows WB-MRI bone marrow screening at high spatial resolution and with a diagnostic accuracy superior to PET-CT.

Diagnostic accuracy of bone metastases detection in cancer patients: Comparison between bone scintigraphy and whole-body FDG-PET

18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has become widely available and an important oncological technique. To evaluate the influence of PET on detection of bone metastasis, we compared the diagnostic accuracy of PET and conventional bone scintigraphy (BS) in a variety of cancer patients.

METHODS

Consecutive ninety-five patients with various cancers, who received both PET and BS within one month, were retrospectively analyzed. A whole-body PET (from face to upper thigh) and a standard whole body BS were performed and these images were interpreted by two experienced nuclear medicine physicians with and without patient information using monitor diagnosis. Each image interpretation was performed according to 8 separate areas (skull, vertebra, upper limbs, sternum and clavicles, scapula, ribs, pelvis, and lower limbs) using a 5-point-scale (0: definitely negative, 1: probably negative, 2: equivocal, 3: probably positive, 4: definitely positive for bone metastasis).

RESULTS

Twenty-one of 95 patients (22.1%) with 43 of 760 areas (5.7%) of bone metastases were finally confirmed. In untreated patients, 12 of 14 bone metastasis positive patients were detected by PET, while 9 of 14 were detected by BS. Three cases showed true positive in PET and false negative in BS due to osteolytic type bone metastases. In untreated cases, PET with and without clinical information showed better sensitivity than BS in patient-based diagnosis. For the purpose of treatment effect evaluation, PET showed better results because of its ability in the evaluation of rapid response of tumor cells to chemotherapy. Out of 10 cases of multiple-area metastases, 9 cases included vertebrae. There was only one solitary lesion located outside of FOV of PET scan in the femur, but with clinical information that was no problem for PET diagnosis.

CONCLUSION

Diagnostic accuracy of bone metastasis was comparable in PET and BS in the present study. In a usual clinical condition, limited FOV (from face to upper thigh) of PET scan may not be a major drawback in the detection of bone metastases because of the relatively low risk of solitary bone metastasis in skull bone and lower limbs.

[18F-FDG PET and bone scintigraphy to search for bone metastasis of lung cancer]

Initial staging of lung cancer is essential to determine the appropriate therapeutic strategy. 18F-FDG PET is currently considered to be the gold standard. 99mTc bisphonate bone scintigraphy has long been indicated to search for bone metastases but it is not know whether this exploration adds further information after an 18F-FDG PET scan. In order to answer this question, two observers unaware of the clinical situation reread PET scans and bone scintigraphies and results compared with other imaging findings. Between February 2001 and March 2004, 39 patients (13F, 26M, 62 +/- 11 yr) underwent 18FFDG PET and bone scintigraphy (mean interval 17 +/- 17 d). When the two explorations agreed for the diagnosis of bone extension, we considered that bone scintigraphy added nothing. When the two explorations were in disagreement, the other imaging examinations, the clinical features and laboratory results during the five-month minimal follow-up were used to establish the reference diagnosis. 18F-FDG PET and bone scintigraphy were in agreement in 29 patients (74%) with positive results in 12 (31%) and negative results in 17 (43%). The two explorations were in disagreement in 10 patients (26%). Among the five disagreement cases with positive bone scintigraphy and no bone anomaly on the 18F-FDG PET, the anomalies were benign and explained by clinical features (3 patients) or were not confirmed by the clinical course and laboratory results (2 patients). Among the 5 cases with a bone anomaly on the 18F FDG PET, no metastasis could be identified during clinical follow-up. Bone scintigraphy does not enable identification of any bone metastases which were not recognized on the PET scan and therefore should not be performed systematically. Using a computed tomography scan with the 18F-FDG PET could further limit the contribution of bone scintigraphy by providing more precision concerning foci identified on the PET scan.

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.

[18F]fluorodeoxyglucose positron emission tomography is more sensitive than skeletal scintigraphy for detecting bone metastasis in endemic nasopharyngeal carcinoma at initial staging

PURPOSE

Bone metastasis occurs frequently in patients with endemic nasopharyngeal carcinoma (NPC). The main objective of this study is to evaluate positron emission tomography (PET) using fluorine-18-labeled fluorodeoxyglucose ([18F]FDG) and conventional skeletal scintigraphy (SS) for detecting bone metastasis at initial staging. Auxiliary objectives are to identify risk factors for bone metastasis and features associated with poor survival in patients with bone metastasis.

PATIENTS AND METHODS

Patients with endemic NPC before initiation of treatment were enrolled. PET and SS were performed at initial staging and compared using McNemar's paired-sample test. Bone metastasis was considered to be present if there was any reliable evidence identified within 1 year after primary diagnosis. Multiple logistic regression and Cox's proportional hazards models were used for auxiliary objectives.

RESULTS

Thirty (15%) of 202 eligible patients were found to have bone metastasis. [18F]FDG PET was found to be more sensitive than SS in the patient-based analysis (P = .006) and in the region-based analysis at the spine (P = .001). Advanced N stage was the only significant risk factor (P < .0001), and the coexistence of hepatic metastasis was a prognosticator of poor survival (P = .017). The survival was not significantly better for patients with bone metastasis undetected at primary staging than for those with initially detectable bone metastasis (P = .620).

CONCLUSION

[18F]FDG PET is more sensitive than SS for detecting bone metastasis in endemic NPC at initial staging, whereas SS can be considered as supplementary in this setting.

Early Detection of Lung Cancer

The overall 5-year survival of lung cancer is only 10% in Europe and 15% in the United States, and progress in curative treatments during the last 20 years has been modest. Late diagnosis of extensive disease is the main reason of failure. Early detection with low-dose spiral computed tomography (CT) is one of the most promising development of clinical research, and continuous improvements in technology can make this instrument more effective than mammography in breast cancer detection. In order to prove the benefit of early detection by reduction of lung cancer mortality, we need to enroll large numbers of high-risk individuals in multicentric prospective randomized trials combining primary prevention by smoking cessation with diagnostic intervention with low-dose spiral CT, optimal management of cancer and minimum damage for healthy individuals. Molecular biology research within early detection trials, combining genomic and proteomic analysis of blood and sputum, may improve the differential diagnosis, define the individual risk of cancer incidence and failure, and help target therapies on the basis of biologic profile.

Pulmonary adenocarcinoma associated with SAPHO syndrome difficult to differentiate from multiple bone metastasis

The patient was a 57-year-old man with a chief complaint of anterior chest pain who was diagnosed with clinical stage IV (c-T2N2M1) non-small-cell lung cancer (adenocarcinoma). Tenderness in the sternoclavicular joint, acne, periodontitis, and palmoplantar pustulosis were evident, and SAPHO syndrome was diagnosed. SAPHO syndrome is a rare disorder that results in synovitis, acne, pustulosis, hyperostosis, and osteomyelitis. Bone scintigraphy showed tracer accumulation in the costal cartilage, sternoclavicular joint, and cervical vertebrae 6-7. Although the bone lesions of SAPHO syndrome were difficult to differentiate from bone metastasis of pulmonary adenocarcinoma, metastatic bone tumors were ruled out by magnetic resonance imaging, computed tomography, and fluorodeoxyglucose positron emission tomography. There have been no previously reported cases of lung cancer with comorbid SAPHO syndrome. We report such a case and discuss the relevant literature, particularly that concerned with the evaluation of bone lesions.

Diagnostic value of MRI in comparison to scintigraphy, PET, MS-CT and PET/CT for the detection of metastases of bone

The initial localization of metastases in the bone in patients with solid tumors has a relatively good prognosis in comparison with visceral metastasization. The early detection of bone marrow metastases allows for a rapid initiation of therapy and a subsequent reduction in the morbidity rate. Modern MRI is superior to the 30-year-old skeletal scintigraphy and bone marrow scintigraphy with respect to sensitivity, specificity, as well as the extent of osteal metastasis. MRI provides substantial, therapy-relevant additional information. MSCT plays an important role in the management of cancer patients in clinical routine and gives an excellent survey of the axial skeleton by demonstrating osteolytic and osteoblastic metastases. Extensive comparative studies of MRI with 18F-FDG-PET and 18F-fluoride-PET have not yet been carried out. Whole body MRI is a very promising new staging method for the oncological diagnosis of solid tumors and the detection of osteal metastases. The adoption of 18F-FDG-PET and 18F-fluoride-PET FDG as well as the side by side PET-CT image fusion and the two in one PET/CT examinations appears to be slightly less sensitive to whole body MRI in the detection of osteal metastases. Larger, prospective multicenter studies are necessary to establish these as new, promising methods for the detection of osteal metastases.

Management of bone metastases in cancer: a review

The presence of bone metastases is indicative of disseminated disease and typically indicates a short-term prognosis in cancer patients. Palliation of symptoms is the primary goal of therapy, with multidisciplinary efforts yielding the best results. New classes of drugs, such as bisphosphonates that significantly increase the time to first skeletal-related event (SRE), represent useful tools for the treatment of bone metastases. While the optimal duration of therapy needs to be defined, there is clinical benefit derived from the use of this class of agents. A potential role for bisphosphonates in the prevention of bone metastases is under current evaluation in clinical trials encompassing different solid tumor types. In combination with ongoing clinical trials, basic research to identify potential novel targets in the tumor cells-bone microenvironment will further define future strategies in the treatment of bone metastases.

Imaging of non-small cell lung cancer

Radiologic evaluation is an important component of the clinical staging evaluation of lung cancer and can greatly influence whether the patient is treated with surgical resection, radiation therapy, chemotherapy, or a combination of these modalities. In addition to staging, the radiologic evaluation of the patient undergoing treatment and subsequent follow-up is important to the clinician for assessing treatment effects and complications. This article discusses the imaging of patients with non-small cell lung cancer and its use in management of these patients.

Cost-effectiveness analysis of strategies introducing FDG-PET into the mediastinal staging of non-small-cell lung cancer from the French healthcare system perspective

AIM

To determine the most cost-effective strategy using PET for mediastinal staging of potentially operable non-small-cell lung cancer (NSCLC).

METHODS

Four decision strategies based on French NSCLC work-up practices for the selection of potential surgical candidates were compared, comprising CT only, PET for negative CT, PET for all with anatomical CT, and CT and PET for all cases. The medical literature was surveyed to obtain values for all variables of interest. Costs were assessed with reimbursements from the French healthcare insurance for the year 1999. Expected cost and life expectancy were calculated for all possible outcomes of each strategy. Sensitivity analysis was performed to determine the effects of changing variables on the expected cost and life expectancy.

RESULTS

Compared with the CT only strategy, CT and PET for all resulted in a relative reduction of 70% of surgery for persons with mediastinal lymph node metastasis. PET for all with anatomical CT was shown to be a cost-effective alternative to the CT only, with life expectancy increased by 0.10 years and expected cost savings of 61 euros. This strategy was more favourable than PET for negative CT. Overall, sensitivity analyses showed the robustness of the results.

CONCLUSION

The introduction of thoracic PET for NSCLC staging is potentially cost-effective in France. Further clinical investigation might help to validate this result.