Incidence of exclusive extrapelvic skeletal metastasis in prostate carcinoma on bone scintigraphy

BACKGROUND Bone is one of the common sites of metastasis from prostate carcinoma.Bone scintigraphy(BS)is one of the most sensitive imaging modalities currently used for bone metastatic work-up.Skeletal metastasis in prostate carcinoma commonly involves pelvic bones but rarely involves extrapelvic-extraspinal sites.AIM To retrospectively analyze the BS data to determine the pattern of skeletal metastases in the prostate carcinoma.METHODS This retrospective observational study involves patients with biopsy-proven prostate carcinoma referred for BS for staging assessment.Patients with abnormal BS were evaluated for the pattern of skeletal involvement and data were pre-sented in descriptive format in the form of percentages.RESULTS A total of 150 patients with biopsy-proven prostate cancer who were referred for staging were included in the study.Thirteen of 150 patients(8.67%)had no abnormal uptake on planar images,ruling out metastatic disease.Twenty-four patients(16%)had heterogeneous uptake in the spine with distribution charac-teristic of degenerative disease and no scan pattern of metastatic disease.Thirty patients(20%)had multifocal uptake involving both pelvic and extra pelvic bones on planar images typical for skeletal metastasis and were considered metastatic.Eighty-three out of 150 patients(55.3%)had increased tracer uptake,which was indeterminate,thus,single photon emission computed tomography-computed tomography(SPECT-CT)was acquired,which showed 51 with metastatic disease,31 benign lesions,and one indeterminate finding.Seven of 150 patients had exclusive pelvic bone uptake,which was found to be metastatic in 4/7 patients in SPECT-CT.Fifty six out of 150 patients showed exclusive extrapelvic tracer uptake,of which only 3 had vertebral metastatic disease.None of the patients with increased uptake exclusively in the extrapelvic-extraspinal location was metastatic.CONCLUSION The incidence of exclusive extrapelvic skeletal metastatic disease in prostate carcinoma is 2%(excluding one patient with indeterminate findings).Further,none of the patients in the current study had exclusive extrapelvic-extraspinal metastasis.Thus,exclusive extrapelvic-extraspinal focal abnormality on planar BS carries a very low probability of metastatic disease and hence,further imaging or SPECT-CT can be safely avoided in such cases.

FEATURE EXTRACTION OF BONES AND SKIN BASED ON ULTRASONIC SCANNING

In the prosthetic socket design, aimed at the high cost and radiation deficiency caused by CT scanning which is a routine technique to obtain the cross-sectional image of the residual limb, a new ultrasonic scanning method is developed to acquire the bones and skin contours of the residual limb. Using a pig fore-leg as the scanning object, an overlapping algorithm is designed to reconstruct the 2D cross-sectional image, the contours of the bone and skin are extracted using edge detection algorithm and the 3D model of the pig fore-leg is reconstructed by using reverse engineering technology. The results of checking the accuracy of the image by scanning a cylinder work pieces show that the extracted contours of the cylinder are quite close to the standard circumference. So it is feasible to get the contours of bones and skin by ultrasonic scanning. The ultrasonic scanning system featuring no radiation and low cost is a kind of new means of cross section scanning for medical images.

Analysis of Clinicopathological Factors Associated with Bone Metastasis in Breast Cancer

Breast cancer is the second leading cause of cancer death in women today. Once breast can- cer metastasizes to bone, mortality increases. Thus, there is an urgent need to identify patients with high risk of bone metastasis, and to find predictive factors for the occurrence of bone metastasis at an earlier stage of breast cancer. Three hundred and sixty patients with pathologically proved breast cancer visit- ing the Department of Nuclear Medicine for whole body bone scan from January 2006 and January 2009 were investigated in this study. Clinicopathological information was obtained, which consisted of age, menopausal status, clinical staging, lymph node stage, histological grade, the expression of estro- gen receptor （ER）, progesterone receptor （PR） and epidermal growth factor receptor 2 （HER2）. Correla- tion between bone metastasis and the associated factors was tested by using the Chi-square test. A Cox multivariate analysis was used to assess the factors which independently contributed to survival after bone metastasis in breast cancer patients. Survival curves were drawn for metastasis-free interval and the independent factors which contributed to survival, using the Kaplan-Meier method. Twenty-four pa- tients were excluded from subsequent analysis. Three hundred and thirty-six enrolled patients ranged in age from 22 to 77 years （mean, 47.8 years）. ER/PR status [ER（＋） vs. ER（-）, 2,2=4.328, P=0.037; ER（＋）PR（＋） vs. ER（＋）PR（-）, ;（2=4.425, P=-0.035] and histological grade （;（2=7.131, P=0.028） were sig- nificantly associated with bone metastasis. ER status （;（2=8.315, P=0.004） and metastasis-free interval （;（2=6.863, P=-0.009） were independent prognostic factors for survival in breast cancer patients with bone metastasis. Our study suggested that ER/PR status and histological grade are risk factors for the development of bone metastasis in breast cancer patients. However, ER status and metastasis-free inter- val are independent prognostic factors for survival in breast cancer patients with bone metastasis. Breast cancer bone metastasis has its unique characteristics, which is helpful to choose the appropriate treat- ment for breast cancer patients with bone metastasis.

^(68)Ga-PSMA PET/CT versus CT and bone scan for investigation of PSA failure post radical prostatectomy

Objective:To evaluate the use of Gallium-68 prostate-specific membrane antigen positron emission tomography/computed tomography(^(68)Ga-PSMA PET/CT),compared with conventional CT abdomen/pelvis(CTAP)and whole body single photon emission CT bone scan(BS),for detection of local or distant metastasis following biochemical failure/recurrence in post-prostatectomy patients.Methods:We conducted a review of our prospectively maintained,institutional database to identify 384 patients with post-prostatectomy biochemical failure/recurrence who underwent PSMA PET/CT,CTAP and BS from February 2015 to August 2017 in Nepean Hospital,tertiary referral centre.The results of the three imaging modalities were analysed for their ability to detect local recurrence and distant metastases.PSMA PET/CT and CTAP imaging were separately performed on the same day and the BS was performed within several days(mostly in 24 h).Difference in detection rates was determined between the modalities and the Chi square test was used to determine significance.Results:A total of 384 patients were identified with a median prostate-specific antigen(PSA)of 0.465 ng/mL(interquartile range =0.19-2.00 ng/mL).Overall,PSMA PET/CT was positive for 245(63.8%)patients whereas CTAP and BS were positive in 174 patients(45.3%).A total of 98 patients(25.5%)had local or distant metastasis detected on PSMA only,while 20 patients(5.2%)had recurrences detected on CTAP but not on PSMA PET/CT.Conclusion:The use of PSMA PET/CT has a higher detection rate of predicted local or distant metastasis compared to CTAP and BS in the staging of patients with biochemical recurrences after radical prostatectomy.

Evaluation of eikonic characteristic of skeletal metastasis of primary pulmonary carcinoma with ^(99)Tc^m methylene diphosphonate whole-body bone scans

Objective： The aim of our study was to explore the eikonic characteristic of skeletal metastasis of primary pul- monary carcinoma. Methods： Whole-body bone scans with 99Tcm methylene diphosphonate were performed in 258 patients with pathologically proven pulmonary carcinoma. The rate of skeletal metastasis, distribution of the metastatic lesions and their characteristics were analyzed. Results： Among the total 258 patients, 142 cases developed skeletal metastasis. The overall rate of skeletal metastasis was 55.0%. The metastases located in axial skeleton were 49.6%, appendicular skeleton 36.0%, trunk bones of the axial skeleton 48.4%, and appendicular girdle skeleton 31.4%. Ribs, thoracic vertebrae, ilium and lumbar vertebrae had a higher rate of skeletal metastasis, which were 38.4%, 24.0%, 21.7%, 20.2%, respectively. 1252 le- sions were detected including 406 at the left side of the body, 387 lesions at the middle position and 459 at the right side of the body. There was no significant difference in terms of number of lesions between left side and right side （X2 = 3.3, P = 0.072）. 1224 skeletal metastatic foci （97.8%） were presented as strong radioactive, 26 （2.1%） as mixed lesions, and 2 （0.2%） as low radioactive. According to the shape of lesions, there were 810 punctate lesions （71.5%）, 159 （14.0%） lump form, 108 （9.5%） strip form and 56 （4.9%） lamellar form. The accumulative skeletal metastasis rate was 28.7% for the patients with one to three lesions. The metastasis rate decreased gradually as the number of metastatic lesions increased. Conclusion： Skeletal metastasis is very common in patients with pulmonary carcinoma. Most skeletal metastases are characterized by strong radio- active and earlier punctate form; they often occur in the trunk bones of axial skeleton or appendicular girdles. The distribution of earlier metastases has not obvious regularity, and advanced skeletal metastases are widely and randomly distributed in the body, which are characterized by often concurrently multiple and polymorphous lesions.

Application of SPECT Combined with CT and MRI in Malignant Tumors Clinical Value in the Diagnosis of Bone Metastasis

Introduction: Bone is the most common site of hematogenous metastasis of malignant tumors. Patients with bone metastasis can have a series of bone related adverse events, which seriously affect the quality of life and survival time of patients. Imaging examination is the main means of clinical diagnosis and evaluation of bone metastasis. Aim of the Work: To evaluate the value of single-photon emission computerized tomography (SPECT) combined with CT and MRI in the diagnosis of bone metastasis of malignant tumors. Subjects and Methods: Eighty patients with bone metastasis from malignant tumors who were admitted to Affiliated Hospital of Chengde Medical College were selected from March 2019 to June 2021. They underwent bone scan with SPECT imaging, CT and MRI separately. The distribution of bone metastasis from primary tumors as well as efficacy of the above three detection methods for bone metastasis was analyzed. Results: A total of 464 lesions were detected by SPECT and CT in the same scanning field, with SPECT detection rate of 92.5% (429/464) and CT detection rate of 77.8% (361/464) (P P P P Conclusion: SPECT may be the preferred screening modality for uspected bone metastases, and when combined with CT and MRI, it can clarify the regional distribution of bone metastasis from malignant tumors and improve the sensitivity, specificity and accuracy of diagnosis with high clinical significance.

When is a bone scan study appropriate in asymptomatic men diagnosed with prostate cancer？

Aims： To determine when a bone scan investigation is appropriate in asymptomatic men diagnosed with prostate cancer. Methods： Between November 2005 and July 2006, 317 men with prostate cancer underwent a bone scan study; 176 men fulfilled the inclusion criteria. Prostate-specific antigen （PSA） cut-offs as well as univariate and multivariate logistic regression analyses using digital rectal examination finding, biopsy Gleason scores and age were performed to determine when a bone scan study is likely to be of value. Results： Only 1/61 men （1.6%） with a serum PSA 〈 20 ng/mL had a positive bone scan. However, 2/38 men （4.7%） with a serum PSA 20.1-40.0 ng/mL, 3/20 men （15%） with a serum PSA 40.1-60.0 ng/mL, 7/19 men （36.8%） with a serum PSA 60.1-100.0 ng/mL and 19/38 men （50%） with a serum PSA 〉 100.0 ng/mL had positive bone scans. Univariate and multivariate logistic regression analyses were uninformative in these groups. Conclusion： Based on our findings, a bone scan is of limited value in asymptomatic prostate cancer patients presenting PSA 〈 20 ng/mL. Therefore, this investigation can be eliminated unless a curative treatment is contemplated. Furthermore, digital rectal examination finding, biopsy Gleason score and age are unhelpful in predicting those who might harbor bone metastasis.

Practice patterns and outcomes of equivocal bone scans for patients with castration-resistant prostate cancer: Results from SEARCH

Objective:To review follow-up imaging after equivocal bone scans in men with castration resistant prostate cancer(CRPC)and examine the characteristics of equivocal bone scans that are associated with positive follow-up imaging.Methods:We identified 639 men from five Veterans Affairs Hospitals with a technetium-99m bone scan after CRPC diagnosis,of whom 99(15%)had equivocal scans.Men with equivocal scans were segregated into“high-risk”and“low-risk”subcategories based upon wording in the bone scan report.All follow-up imaging(bone scans,computed tomography[CT],magnetic resonance imaging[MRI],and X-rays)in the 3 months after the equivocal scan were reviewed.Variables were compared between patients with a positive vs.negative follow-up imaging after an equivocal bone scan.Results:Of 99 men with an equivocal bone scan,43(43%)received at least one follow-up imaging test,including 32/82(39%)with low-risk scans and 11/17(65%)with high-risk scans(p=0.052).Of follow-up tests,67%were negative,14%were equivocal,and 19%were positive.Among those who underwent follow-up imaging,3/32(9%)low-risk men had metastases vs.5/11(45%)high-risk men(p=0.015).Conclusion:While 19%of all men who received follow-up imaging had positive follow-up imaging,only 9%of those with a low-risk equivocal bone scan had metastases versus 45%of those with high-risk.These preliminary findings,if confirmed in larger studies,suggest follow-up imaging tests for low-risk equivocal scans can be delayed while high-risk equivocal scans should receive follow-up imaging.

EFFECT OF INTERNAL FIXATION PLATES ON MICROCIRCULATION IN UNDER-PLATE CORTICAL BONES MICROANGIOGRAPHY AND SCANNING ELECTRONMICROSCOPY

To elucidate the effect of the internal fixation plates on the local bone blood sapply, we used microangiography and scanning electron microscopy to observe the morphological changes of microcirculation in the cortical bones obtained from intact rabbit tibiae on which plates of two different stiffness had been fixed for comparison. The results indicated that both rigid stainless steel plate and less rigid methyl methacrylate plate could induce the bone microcirculation under the plate to undergo a process from early depression to late reactive recruitment. The features of the microcircuiation recruitment such as vascular number, arrangement and dilatation varied with plates of different stiffness and were more obvious in the cortex fixed by rigid stainless steel plate.

Malignant giant cell tumor in the left upper arm soft tissue of an adolescent:A case report

BACKGROUND Giant cell tumor of soft tissue(GCT-ST)is an extremely rare low-grade soft tissue tumor that is originates in superficial tissue and rarely spreads deeper.GCT-ST has unpredictable behavior.It is mainly benign,but may sometimes become aggressive and potentially increase in size within a short period of time.CASE SUMMARY A 17-year-old man was suspected of having a fracture,based on radiography following left shoulder trauma.One month later,the swelling of the left shoulder continued to increase and the pain was obvious.Computed tomography(CT)revealed a soft tissue mass with strip-like calcifications in the left shoulder.The mass invaded the adjacent humerus and showed an insect-like area of destruction at the edge of the cortical bone of the upper humerus.The marrow cavity of the upper humerus was enlarged,and a soft tissue density was seen in the medullary cavity.Thoracic CT revealed multiple small nodules beneath the pleura of both lungs.A bone scan demonstrated increased activity in the left shoulder joint and proximal humerus.The mass showed mixed moderate hypointensity and hyperintensity on T1-weighted images,and mixed hyperintensity on T2-weighted fat-saturated images.The final diagnosis of GCT-ST was confirmed by pathology.CONCLUSION GCT-STs should be considered in the differential diagnosis of soft tissue tumors and monitored for large increases in size.

Correlations of single photon emission computed tomography joints scan and bone metabolic markers in active rheumatoid arthritis

Objective To explore the correlation between quantitative value of joint bone scan by single photon emission computed tomography(SPECT)and serum bone metabolic markers in patients with active rheumatoid arthritis(RA).Methods Clinical data of 60 newly diagnosed RA patients were retrospectively collected in Department