Whole-body bone marrow MRI in patients with metastatic disease to the skeletal system

PURPOSE: The purpose of this study was to evaluate the diagnostic potential of a whole-body bone marrow MR protocol in the detection of bone metastases. METHOD: Whole-body bone marrow MRI was performed in 18 patients with known malignant tumors and suspected bone metastases. The imaging protocol consisted of fast T1-weighted and STIR sequences applied in different anatomical positions covering the whole skeleton. MRI findings indicating bone metastases were compared with findings from bone scintigraphy. Metastatic lesions were confirmed by follow-up MR examinations, bone scintigraphy, radiography, or CT. RESULTS: A total number of 216 lesions were detected with MRI in comparison with 159 lesions detected with bone scintigraphy. Follow-up examinations confirmed 105 lesions. MRI detected 96 (91.4%) of the confirmed lesions, whereas bone scintigraphy detected 89 (84.8%). The entire examination, including patient positioning and changing of imaging coils, required 45 min of room time. CONCLUSION: Whole-body bone marrow MRI as used in this study is an effective method for evaluating the entire skeletal system in patients with suspected metastatic disease.     

Bone scan flare predicts successful systemic therapy for bone metastases

Changes in osteoblast function, assessed by serial bone scans and serum alkaline phosphatase bone isoenzyme (ALP-Bl) and osteocalcin, have been studied in 53 patients receiving systemic therapy for bone metastases from advanced breast cancer. In 12/16 patients with healing of lytic disease on x-ray a paradoxical deterioration in the bone scan appearances after 3 mo treatment was seen. This was characterized by increased activity in baseline lesions and the appearance of new foci of tracer uptake; changes which are indistinguishable from progressive disease. After 6 mo successful treatment the bone scan improved with reduced tracer uptake and no new lesions since the 3-mo scan. New lesions appearing after 6 mo indicated progressive disease. These changes are attributed to a flare in osteoblast activity induced by successful systemic therapy and confirmed by a transient rise in osteocalcin and ALP-Bl. After 1 mo of treatment 15/16 responders showed a rise in both parameters compared with only 5/23 nonresponders (p = less than 0.001). The flare response is the rule rather than the exception after successful systemic therapy for bone metastases. The appearance of new lesions or increasing activity in known lesions during the first 3 mo is as likely to herald radiological response as disease progression.     

FDG-PET and CT patterns of bone metastases and their relationship to previously administered anti-cancer therapy

Purpose To assess ¹⁸F-fluorodeoxyglucose (FDG) uptake in bone metastases in patients with and without previous treatment, and compare positive positron emission tomography (PET) with osteolytic or osteoblastic changes on computed tomography (CT).Methods One hundred and thirty-one FDG-PET/CT studies were reviewed for bone metastases. A total of 294 lesions were found in 76 patients, 81 in untreated patients and 213 in previously treated patients. PET was assessed for abnormal FDG uptake localised by PET/CT to the skeleton. CT was evaluated for bone metastases and for blastic or lytic pattern. The relationship between the presence and pattern of bone metastases on PET and CT, and prior treatment was statistically analysed using the chi-square test.Results PET identified 174 (59%) metastases, while CT detected 280 (95%). FDG-avid metastases included 74/81 (91%) untreated and 100/213 (47%) treated lesions (p<0.001). On CT there were 76/81 (94%) untreated and 204/213 (96%) treated metastases (p NS). In untreated patients, 85% of lesions were seen on both PET and CT (26 blastic, 43 lytic). In treated patients, 53% of lesions were seen only on CT (95 blastic, 18 lytic). Of the osteoblastic metastases, 65/174 (37%) were PET positive and 98/120 (82%), PET negative (p<0.001).Conclusion The results of the present study indicate that when imaging bone metastases, prior treatment can alter the relationship between PET and CT findings. Most untreated bone metastases are PET positive and lytic on CT, while in previously treated patients most lesions are PET negative and blastic on CT. PET and CT therefore appear to be complementary in the assessment of bone metastases.     

骨转移瘤18F—FDGPET／CT影像学表现分析

目的分析骨转移瘤的18F-脱氧葡萄糖（FDG）PET／CT影像学表现。方法140例18F—FDGPET／CT检查病例,按病灶的4种CT形态（成骨改变、溶骨改变、混合改变及无改变）分组,探讨肿瘤骨转移灶代谢表现与形态表现之间的关系,进一步治疗情况与转移灶代谢表现的关系。采用SPSS10．0软件,行Mann—Whitney检验及x2检验。结果140例患者分未治疗组78例（55．7％）,治疗（化疗及内分泌）组62例（44．3％）。共检出病灶1658个,CT示成骨病灶415个（25．0％）,溶骨病灶567个（34．2％）,混合病灶177个（10．7％）,无改变病灶499个（30．1％）。对未治疗组1045个病灶平均标准摄取值（SUVmax。）行Mann—Whitney检验,混合病灶、溶骨病灶SUVmax高于成骨病灶、无改变病灶（SUVmax。中位值分别为5．7,5．2,4．8及4．6,Z=-4．680,-6．067,-2．237,-4．635,P均〈0．05）;治疗组与未治疗组行,检验,未治疗组以溶骨性改变（39．6％）为多,治疗组以成骨性改变（35．9％）为多,组间病灶组成明显不同（x2=67．8,P〈0．05）,治疗组代谢水平明显低于未治疗组（SUVmax中位值分别为4．9及4．6,Z=-4．315,P〈0．05）。结论骨转移病灶形态表现不同,其代谢表现差异明显,溶骨病灶的SUVmax。明显大于无溶骨病灶;化疗及内分泌治疗能通过对病灶转归的改变影响病灶形态及相应代谢表现。     

Bone metastases in breast cancer: higher prevalence of osteosclerotic lesions

PURPOSE: It is well known that bone metastases from breast cancer usually show osteolytic changes. We retrospectively analysed the computed tomography (CT) appearance of bone metastases to quantify the distribution of lytic, mixed and sclerotic changes in a series of patients presenting with neoplastic bone involvement from breast cancer. MATERIALS AND METHODS: Between 1996 and 2005, 468 women with a diagnosis of breast cancer were referred to our department for staging or follow-up CT examinations. Staging CT examinations detected systemic metastases in 142/468 patients, 60 of which had bone involvement. Patients with a second primary tumour or bone metabolic disorders were excluded from this retrospective analysis. RESULTS: In patients with bone metastases, CT identified 18 with osteolytic lesions (30%), 32 with osteosclerotic lesions (53.3%) and ten with mixed lesions (16.7%). Analysis of the cases observed for the first time during the 1996-2000 period showed osteolytic lesions in 53.6% (15/28), osteosclerotic lesions in 32.1% (9/28) and mixed lesions in 14.3% (4/28). Results were 9.4% (3/32), 71.9% (23/32) and 18.7% (6/32), respectively, for the same groups in the 2001-2005 period. Histological analysis of all cases included 81.9% of infiltrative ductal carcinoma, 11.2% of infiltrative lobular carcinoma, 3.7% of ductal lobular mixed carcinoma and 3% of medullar carcinoma. We found no statistically significant correlation between histological type of breast cancer and radiological appearance of bone metastasis. A significant difference between patients treated with or without zoledronic acid was observed, with a higher prevalence of osteosclerotic lesions in the former group of patients (p<0.05). CONCLUSIONS: We observed an increasing prevalence of osteosclerotic bone metastasis when comparing the 1996-2000 period with the 2001-2005 period. The significance of these distribution changes is not clear. However, we found a significant correlation of osteosclerotic lesions with zoledronic acid treatment. The advent of third generation bisphosphonates may have changed the CT appearance of bone metastasis from breast cancer.     

A prospective analysis of CT density measurements of bone metastases after treatment with zoledronic acid

Objective The objective was to prospectively determine CT density changes in bone metastases, before and after intravenous zoledronic acid for a maximum period of 12 months. Patients and methods Twenty-three consecutive patients presented with bone metastases and underwent therapy with zoledronic acid from December 2004. All patients underwent CT of the chest, abdomen, and pelvis. Bone density, measured in Hounsfield units (HU), was determined by segmenting lesions in the same anatomical area of the metastasis sites on the axial images of the sequential series of CT examinations. The effects of zoledronic acid were evaluated by calculating absolute and relative increases in bone density. Results The patients presented with multiple metastases in 65% of the cases. When compared with the baseline, all groups demonstrated a significant increase in bone density, which significantly (p < 0.01) correlated with the number of zoledronic acid administrations. There was increased bone density of at least 100% in 57%, and an increase of at least 50% in 87% of the patients. This increase was significant in both lytic and sclerotic metastases after 3 months of therapy. No significant bone density difference was found in normal-appearing bone. Conclusion Bone density measured by CT increases at metastatic sites after zoledronic acid treatment, regardless of the type of metastasis, in contrast to apparently normal bone.     

CT appearance of bone metastases detected with FDG PET as part of the same PET/CT examination

PURPOSE: To retrospectively evaluate lesion findings at computed tomography (CT) performed as part of a combined positron emission tomography (PET)/CT examination in patients suspected of having metastatic bone lesions-lesions that were detected with fluorine 18 fluorodeoxyglucose (FDG) PET as part of the same examination-and to correlate the CT and FDG PET findings. MATERIALS AND METHODS: This HIPAA-compliant study had institutional review board approval, and the need for patient informed consent was waived. Three hundred fifty-nine consecutive patients (191 male patients, 168 female patients; mean age, 56.9 years; age range, 8-92 years) underwent PET/CT. PET images were first reviewed by nuclear medicine physicians who had no clinical information regarding the presence or absence of bone metastasis by using a five-point grading system (0, a lesion was definitely negative for metastasis; 1, a lesion was probably negative; 2, a lesion was equivocal; 3, a lesion was probably positive; and 4, a lesion was definitely positive). For lesions assigned a grade of 3 or 4 at PET, CT characteristics such as the presence or absence of morphologic changes or accompanying findings (including bone destruction) were assessed by radiologists on the CT images obtained during the same imaging session. RESULTS: One hundred seventy-nine lesions in 55 patients were considered to be probable or definite bone metastases at PET. One hundred thirty-three of these lesions in 33 patients were clinically confirmed to be bone metastases at follow-up and/or histopathologic examination. CT revealed osteolytic changes in 41 (31%) and osteoblastic changes in 21 (16%) of the 133 lesions, but no or nonspecific changes were seen at CT in 49 (37%) and 22 lesions (17%), respectively. Of the 179 lesions suspected at PET, 46 ultimately proved to be nonosseous or false-positive for bone metastasis. Of these 46 lesions, 38 were not located in the bone but in adjacent tissues such as the pleura. CONCLUSION: CT images obtained as part of PET/CT scanning were useful in yielding the precise location of bone lesions and thus helping avoid misdiagnosis of bone metastasis; however, CT revealed morphologic changes in only half of the lesions assigned a grade of 3 or 4 at PET.     

Comparison of diagnostic ability between 99mTc-MDP bone scan and 18F-FDG PET/CT for bone metastasis in patients with small cell lung cancer

Objective

The aim of this study was to compare the diagnostic ability of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) with that of ^99mTc-methylene diphosphonate (^99mTc-MDP) bone scan for bone metastasis in staging patients with small cell lung cancer (SCLC).

Methods

Ninety-five patients with SCLC who underwent both ¹⁸F-FDG PET/CT and ^99mTc-MDP bone scan for initial staging work-up were retrospectively enrolled. All ¹⁸F-FDG PET/CT and bone scan images were visually assessed. Bone metastasis was confirmed by histopathological results and all available clinical information.

Results

Of 95 patients with SCLC, metastatic bone lesions were found in 30 patients, and 84 metastatic lesions were evaluated on a lesion-basis analysis. The sensitivity of ¹⁸F-FDG PET/CT was 100?% on a per-patient basis and 87?% on a per-lesion basis, and there was no false-positive lesion on PET/CT images. In contrast, the sensitivity of the bone scan was 37?% on a per-patient basis and 29?% on a per-lesion basis. The bone scan showed 11 false-positive lesions. The bone scan detected two metastatic lesions that were not detected by PET/CT, which were outside the region scanned by PET/CT. On follow-up bone scan, 21 lesions that were not detected by the initial bone scan but were detected by PET/CT were newly detected.

Conclusions

In patients with SCLC, ¹⁸F-FDG PET/CT showed higher detection rate of bone metastasis than ^99mTc-MDP bone scan. Thus, ¹⁸F-FDG PET/CT can replace bone scan in staging patients with SCLC.     

Detection of bone metastases in patients with prostate cancer by <Superscript>18</Superscript>F fluorocholine and <Superscript>18</Superscript>F fluoride PET–CT: a comparative study

Purpose  The aim of this prospective study was to compare the potential value of ¹⁸F fluorocholine (FCH) and ¹⁸F fluoride positron emission tomography (PET)–CT scanning for the detection of bony metastases from prostate cancer. Methods  Thirty-eight men (mean age, 69 ± 8 years) with biopsy-proven prostate cancer underwent both imaging modalities within a maximum interval of 2 weeks. Seventeen patients were evaluated preoperatively, and 21 patients were referred for post-operative evaluation of suspected recurrence or progression based on clinical algorithms. The number, sites and morphological patterns of bone lesions on ¹⁸F FCH and ¹⁸F fluoride PET–CT were correlated: Concordant lesions between the two modalities with corresponding changes on CT were considered to be positive for malignancy; discordant lesions were verified by follow-up examinations. The mean follow-up interval was 9.1 months. Results  Overall, 321 lesions were evaluated in this study. In a lesion-based analysis, a relatively close agreement was found between these two imaging modalities for detection of malignant bone lesions (kappa = 0.57), as well as in a patient-based analysis (kappa = 0.76). Sixteen malignant sclerotic lesions with a high density were negative in both ¹⁸F FCH and ¹⁸F fluoride PET–CT [mean Hounsfield unit (HU), 1,148 ± 364]. There was also a significant correlation between tracer intensity by SUV and density of sclerotic lesions by HU both in ¹⁸F FCH PET–CT (r = −0.28, p < 0.006) and ¹⁸F fluoride PET–CT (r = −0.20, p < 0.05). The sensitivity, specificity and accuracy of PET–CT in the detection of bone metastases in prostate cancer was 81%, 93% and 86% for ¹⁸F fluoride, and 74% (p = 0.12), 99% (p = 0.01) and 85% for FCH, respectively. ¹⁸F FCH PET–CT led to a change in the management in two out of 38 patients due to the early detection of bone marrow metastases. ¹⁸F fluoride PET–CT identified more lesions in some patients when compared with ¹⁸F FCH PET–CT but did not change patient management. Conclusion  FCH PET–CT may be superior for the early detection (i.e. bone marrow involvement) of metastatic bone disease. In patients with FCH-negative suspicious sclerotic lesions, a second bone-seeking agent (e.g. ¹⁸F fluoride) is recommended. ¹⁸F fluoride PET–CT demonstrated a higher sensitivity than ¹⁸F FCH PET–CT, but the difference was not statistically significant. Furthermore, ¹⁸F fluoride PET could be also negative in highly dense sclerotic lesions, which presumably reflects the effect of treatment. It will be important to clarify in future studies whether these lesions are clinically relevant when compared with metabolically active bone metastases.     

Role of 18F-FDG PET/CT in differentiation of a benign lesion and metastasis on the ribs of cancer patients

ObjectiveIncidental 18-Fluoro-2-deoxyglucose positron emission tomography (¹⁸F-FDG) uptake in the ribs is a relatively common finding on positron emission tomography/computed tomography (PET/CT) images of cancer patients. This study examined the role of ¹⁸F-FDG PET/CT in differentiating between benign lesions and metastases on the ribs.MethodsThis study included 264 lesions in 172 PET/CT cases with underlying malignancy showing newly developed indeterminate ¹⁸F-FDG rib uptake between June 2009 and May 2010. Patients with more than five FDG rib uptakes or hematologic malignancy were excluded. Malignancy was confirmed either histologically or by imaging studies, and clinical follow-up with serial images was at least 6 months. The maximum standardized uptake value (SUVmax) of the rib lesion was recorded. The FDG uptake patterns (focal or segmental; discrete or non-discrete) and CT findings (evidence of fracture, soft tissue lesions, osteoblastic and/or osteolytic lesions) were recorded.ResultsThere were 206 benign lesions and 58 metastases. The SUVmax was significantly higher in the metastatic group (3.0±1.8) than in the benign group (2.5±1.1), (P= .014). For the differential diagnosis between benign and metastatic lesions, the best SUVmax cut-off was determined to be 2.4. Significant indicators for metastasis were a segmental FDG uptake pattern (OR=10.262, 95% CI 4.151–25.371), presence of an osteoblastic/-lytic lesion (OR=22.903, 95% CI 10.468 to 50.108) and the absence of fractures on CT (OR=291.629, 95% CI 39.09–2175.666).ConclusionSUVmax alone is not sufficient to differentiate benign and metastatic rib lesions in cancer patients. The diagnostic accuracy can be further increased when findings of the CT part of PET/CT are considered.     

The role of computed tomography in the detection of bone metastases in breast cancer patients

Computed tomography (CT) of bone was carried out in 20 patients with breast cancer, all of whom had abnormal radionuclide uptake on skeletal scintigrams but normal conventional radiographs. Twenty-eight sites were examined and 13 showed metastases in 11 patients. Five of these patients had no evidence of extra-skeletal recurrent disease. Follow-up at eight of these sites showed healing, sclerosis or progression, all of which correlated well with clinical findings. CT showed benign causes of radionuclide accumulation in three patients (7 sites) but no abnormality in six patients (8 sites). None of these patients has subsequently developed bone metastases. CT is superior to conventional radiographs in the diagnosis of skeletal metastases and should be carried out when skeletal scintigraphy is positive and conventional examinations are normal.     

Bone scan "flare" in patients irradiated to formerly false negative bone metastasis]

We discuss three cases irradiated to their bone metastases. 99mTc-MDP bone scan before irradiation showed normal uptake in the lesions. In all the cases, the irradiation therapy was effective, but focal increased uptake area corresponding to the site of bone metastasis was revealed by the follow-up bone scan one to three months after irradiation. We concluded that the change of tracer uptake was so-called flare in formerly false negative lesion. The cause of this phenomenon was considered either elevation of osteoblastic activity with control of tumor or progression of osteolysis until tumor got well-controlled.     

CT of melanoma liver metastases: is the examination without contrast media superfluous?

The current method of evaluating hypervascular liver metastases with CT includes both contrast enhanced and unenhanced studies. The necessity of performing both examinations for the detection of liver metastases in the workup of malignant melanoma has not been specifically addressed. This study evaluates potential additional information derived from an unenhanced examination of the liver. We studied 55 patients with malignant melanoma who had both contrast enhanced and unenhanced CT examinations performed during the workup and staging of their disease. Sixteen patients had 89 measurable liver lesions seen on enhanced CT. Three patients had liver lesions that were too numerous to accurately measure. Unenhanced CT demonstrated only 62% of the measurable lesions. All liver lesions seen on the unenhanced images were identified on the enhanced studies. Only one metastasis was found to be comparatively smaller on the enhanced examinations. The unenhanced examinations detected no additional lesions. It is reasonable to perform only an enhanced examination during the workup and staging of malignant melanoma liver metastases.     

CT diagnosis of intrasplenic metastasis from ovarian carcinoma

Intrasplenic metastases from ovarian carcinoma cannot be always demonstrated intraoperatively. CT is the most important imaging modality of choice for staging and follow-up ovarian cancer; in this study we searched CT appearances of intrasplenic metastases from ovarian carcinoma. We retrospectively reviewed imaging histories of the patients with ovarian cancer from the radiology information system, and found 12 patients with intrasplenic metastasis. All patients underwent abdominal CT with 16-MDCT. We searched number, density and maximum diameters of splenic metastasis. The growing rate of three lesions, which were followed up by CT, was calculated. Serum cancer antigen (CA) 125 levels were noted. We also evaluated clinical history and pathology reports of all patients. Splenic metastases, solitary or multiple, were detected most frequently during the follow-up (1-14 years after initial diagnosis) and most were associated with other sites of recurrence. The diameters of lesions ranged from 4 to 85mm. All lesions appeared hypodense except for one lesion with dense calcification. Densities of lesions ranged from 12 to 208 Hounsfield units (mean, 49±51HU). Most lesions appeared as solid well-defined nodules; however some lesions had lobulated and irregular contours with an infiltrative pattern. The growing rates of three lesions were 0.72mm/month, 1.75mm/month and 2.70mm/month. Eight patients had elevated serum CA 125 levels (40-1256U/mL). We concluded that CT can demonstrate intraparenchymal and infiltrative splenic metastasis in patients with ovarian cancer even in the absence of increased CA 125 levels.     

Role of whole-body diffusion-weighted MRI in detecting bone metastasis

Purpose

The aim of this study was to compare the results of whole-body diffusion-weighted magnetic resonance (DW-MR) imaging with staging based on computed tomography (CT) and nuclear scintigraphy using Tc99m results as the standard of reference.

Methods and materials

Seventeen patients with known malignant tumours were included in the study. The thorax and the abdomen were imaged using breath-hold diffusion-weighted imaging and T1-weighted imaging sequences in the coronal plane. Location and size of osseous metastases were documented by two experienced radiologists. Whole-body DW-MR imaging findings were compared with results obtained at skeletal scintigraphy and CT bone survey.

Results

The mean examination time for whole-body DW-MR imaging was 25.5 min. All bone metastases regardless of the size were identified with whole-body DW-MR imaging; MR imaging depicted more bone metastases than CT. Skeletal scintigraphy depicted osseous metastases in 13 patients (with greater sensitivity to the lower limb), whereas whole-body DW-MR imaging revealed osseous metastases in 13 patients (with greater sensitivity to the spine). DW-MR did not show good results for detection of rib cage metastases. The additional osseous metastases seen with MR imaging were confirmed at follow-up examinations and some had a change in therapy. MR identified 22 % more metastatic lesions when compared to bone scintigraphy and 119 % when compared to CT. Bone scintigraphy identified 80 % more metastatic lesions when compared to CT. On a per-patient basis, whole-body DW-MR imaging revealed sensitivity and specificity values of 100 %.

Conclusion

Whole-body DW-MR imaging was more sensitive in the detection of osseous metastases than were skeletal scintigraphy and CT bone survey.     

Usefulness of low-dose CT in the detection of pulmonary metastasis of gestational trophoblastic tumours

AIM: To determine whether a low-dose spiral chest computed tomography (CT) examination could replace standard-dose chest CT in detecting pulmonary metastases in patients with gestational trophoblastic tumour (GTT). MATERIALS AND METHODS: In a prospective investigation, 67 chest CT examinations of 39 GTT patients were undertaken. All the patients underwent CT examinations using standard-dose (150 mAs, pitch 1, standard reconstruction algorithm) and low-dose (40 mAs, pitch 2, bone reconstruction algorithm) protocols. Two radiologists interpreted images independently. A metastasis was defined as a nodule within lung parenchyma that could not be attributed to a pulmonary vessel. The number of metastases detected with each protocol was recorded. The size of each lesion was measured and categorized as <5, 5-9.9, and > or = 10 mm. Wilcoxon's signed rank test was used to assess the difference between the numbers of lesion detected by the two protocols. RESULTS: The CT dose index (CTDI) for the standard-dose and low-dose CT protocols was 10.4 mGy and 1.4 mGy, respectively. One thousand, six hundred, and eighty-two metastases were detected by standard-dose CT, and 1460 lesions by the low-dose protocol. The numbers detected by low-dose CT were significantly less than those detected by standard-dose CT (Z=-3.776, p<0.001), especially for nodules smaller than 5mm (Z=-4.167, p<0.001). However, the disease staging and risk score of the patients were not affected by use of the low-dose protocol. CONCLUSION: Low-dose chest CT can be used as a staging and follow-up procedure for patients with GTT.     

Comparison of computed tomography and conventional radiology in the assessment of treatment response of lytic bony metastases in patients with carcinoma of the breast

Full skeletal survey, localised radiographs and computed tomography (CT) examinations were compared with clinical assessment in the evaluation of treatment response of bony metastases in 20 patients with carcinoma of the breast. Conventional radiology, skeletal survey and localised views compared poorly with clinical assessment agreeing in only 35% and 50% respectively. CT concurred with the clinical assessment in 65% of patients, particularly with respect to healing (86%). CT predicted the effect of treatment in six additional patients and this was confirmed on follow-up assessment. It is suggested that the use of skeletal surveys in monitoring treatment response is limited and that for critical evaluation of treatment CT should be the method of choice.     

Impact of [<Superscript>18</Superscript>F]FDG-PET on the primary staging of small-cell lung cancer

Purpose The purpose of this study was to evaluate the impact of [¹⁸F]fluorodeoxy-d-glucose positron emission tomography (FDG-PET) on the primary staging of patients with small-cell lung cancer (SCLC).Methods FDG-PET was performed in 120 consecutive patients with SCLC during primary staging. In addition, brain examinations with both FDG-PET and cranial magnetic resonance imaging (MRI) or computed tomography (CT) were performed in 91 patients. Results of FDG-PET were compared with those of conventional staging procedures. FDG-PET detected markedly increased FDG uptake in the primary tumours of all 120 patients (sensitivity 100%).Results Complete agreement between FDG-PET results and other staging procedures was observed in 75 patients. Differences occurred in 45 patients at 65 sites. In 47 sites the FDG-PET results were proven to be correct, and in ten, incorrect. In the remaining eight sites, the discrepancies could not be clarified. In 14/120 patients, FDG-PET caused a stage migration, correctly upstaging ten patients to extensive disease and downstaging three patients by not confirming metastases of the adrenal glands suspected on the basis of CT. Only 1/120 patients was incorrectly staged by FDG-PET, owing to failure to detect brain metastases. In all cases the stage migration led to a significant change in the treatment protocol. Sensitivity of FDG-PET was significantly superior to that of CT in the detection of extrathoracic lymph node involvement (100% vs 70%, specificity 98% vs 94%) and distant metastases except to the brain (98% vs 83%, specificity 92% vs 79%). However, FDG-PET was significantly less sensitive than cranial MRI/CT in the detection of brain metastases (46% vs 100%, specificity 97% vs 100%).Conclusion The introduction of FDG-PET in the diagnostic evaluation of SCLC will improve the staging results and affect patient management, and may reduce the number of tests and invasive procedures.     

第三代双源双能CT虚拟去钙骨髓成像在椎体成骨性骨转移瘤评价中的价值

目的 探讨第三代双源双能CT虚拟去钙骨髓成像(简称骨髓成像)用于评价椎体成骨性骨转移瘤的临床价值。方法 回顾性分析2017年11月至2018年9月在山西医科大学第一医院就诊的48例骨外恶性肿瘤患者[男性27例、女性21例,年龄(62.4±10.5)岁]的椎体骨转移情况,所有患者同期均行双源双能CT成像与9 Tcm-亚甲基二膦酸盐(MDP)全身骨显像,以临床随访诊断或病理诊断结果为标准,比较99Tcm-MDP全身骨显像、常规CT及骨髓成像3种方法在椎体成骨性骨转移瘤中的诊断价值。在骨髓成像图像上测量骨髓密度(CT值),3种方法诊断椎体成骨性骨转移瘤的灵敏度、特异度、阳性预测值、阴性预测值和准确率的比较采用χ2检验,采用t检验比较椎体转移灶的骨髓CT值和正常椎体的骨髓CT值,采用受试者工作特征曲线分析骨髓CT值。结果 48例患者共计598个椎体,确诊成骨性骨转移瘤的椎体135个。99Tcm-MDP全身骨显像诊断数为127个,常规CT诊断数为119个,骨髓成像诊断数为129个,骨髓成像诊断的灵敏度、特异度、阳性预测值、阴性预测值和准确率分别为95.56%、94.82%、84.31%、98.65%和94.98%。99Tcm-MDP全身骨显像、常规CT、骨髓成像的阴性预测值(98.17%、96.60%、98.65%)和准确率(92.81%、95.82%、94.98%)间的差异均无统计学意义(χ2=4.891、5.591,P=0.087、0.061);99Tcm-MDP全身骨显像与骨髓成像的灵敏度(94.07%vs. 95.56%)、特异度(92.44%vs. 94.82%)及阳性预测值(78.40%vs. 84.31%)间的差异均无统计学意义(χ2=0.301、2.190、1.811,P=0.583、0.139、0.178);病变椎体转移灶的骨髓密度较正常椎体的骨髓密度低[(-588.96±332.37) HUvs.(-55.03±75.62) HU],差异有统计学意义(t=31.906,P=0.000)。骨髓密度的曲线下面积为0.99,临界值为-119.6 HU(灵敏度和特异度分别为97.80%和96.50%)。结论 第三代双源双能CT虚拟去钙骨髓成像可用于检测椎体成骨性骨转移瘤。     

Non-contrast-enhanced CT findings of high attenuation within metastatic cervical lymph nodes in patients with stage I or II tongue carcinoma during a follow-up period

We present the non-contrast-enhanced CT finding of high attenuation within metastatic regional lymph nodes in two patients with stage I or II tongue carcinoma during a follow-up period. The attenuation values of these lesions were approximately 70 HU or more. One patient had a level I node, and the other had a level II node. Contrast-enhanced CT failed to reveal these hyperattenuated areas within the nodes. Histopathologic examination revealed that these hyperattenuated areas were strongly correlated with the area of marked keratinization of metastatic foci. If contrast-enhanced CT had been the only imaging technique used, these lesions might have been overlooked. The clinician should be aware of the characteristic findings of non-contrast-enhanced, as well as contrast-enhanced, CT when investigating lymph node metastases at an early stage in patients with stage I or II tongue carcinoma during the follow-up period.