Bladder tumor is the most common malignant tumor in urinary system and always com- panied with lymph node metastasis. The accurate staging plays a significant role in treatment for bladder tumor and prognostic evaluat...Bladder tumor is the most common malignant tumor in urinary system and always com- panied with lymph node metastasis. The accurate staging plays a significant role in treatment for bladder tumor and prognostic evaluation, and the distant metastasis predicts worse prognosis. The objective of this study was to assess the clinical significance of 18F-FDG PET/CT imaging in diagnosing bladder tumor metastasis lesions. A retrospective analysis of 60 patients with bladder tumor from October 2008 to May 2010 was done. The patients were stratified based on the imaging technique. Among all 60 cases, besides the primary lesion, 81 suspected lesions were spotted and 73 confirmed as metastasis, including 50 lymph node metastases, 22 distant metastases, and 1 bone metastasis. For PET/CT imaging, its sensitivity was 94.5%, specificity 87.5%, positive predictive value 98.6%, negative predictive value 63.6% and accuracy 93.8% respectively. For CT, its sensitivity was 82.2%, specificity 50%, positive predictive value 93.8%, negative predictive value 23.5% and accuracy 79% respectively. PET/CT im- aging was superior to CT in sensitivity, specificity and accuracy. In conclusion, 18F-FDG PET/CT imaging is more significant in diagnosing bladder tumor metastasis lesions.展开更多
BACKGROUND Gastric cancer (GC) with bone metastasis is rare, and rib metastasis is even lesscommon. The clinical prognosis of GC with bone metastasis is poor given the lackof an effective treatment.CASE SUMMARY A 70 y...BACKGROUND Gastric cancer (GC) with bone metastasis is rare, and rib metastasis is even lesscommon. The clinical prognosis of GC with bone metastasis is poor given the lackof an effective treatment.CASE SUMMARY A 70 year old man was referred to Shaoxing People’s Hospital with left chest painand slight dyspnea. Chest computed tomography (CT) revealed a metastaticlesion in the left 3rd rib. Esophagogastroduodenoscopy revealed several ulcers inthe angle and antrum of the stomach, and tumor biomarkers including CEA andCA-199 were clearly increased. In addition, lymph node metastasis in the lessercurvature of the stomach was identified by positron emission tomography/CTscanning. Further pathological examination confirmed metastatic adenocarcinomain the rib and medium-low differentiated adenocarcinoma in the gastric space.The patient had GC with rib metastasis, and was clinically staged as T3NxM1 (IVB).Based on multidisciplinary team opinions, the patient received five courses ofchemotherapy (CAPOX plus aptinib), and then underwent rib resection andlaparoscopic radical distal gastrectomy. The patient started four courses ofchemotherapy after surgery, and then capecitabine and aptinib were administeredorally for 3 mo. Follow-up was performed on an outpatient basis usingabdominal/chest CT and tumor biomarkers. The patient exhibited an overallsurvival greater than 2 years, and the disease-free survival was approximately 18mo. His adverse events were tolerable.CONCLUSION The incidence of GC with rib metastases is extremely low, and patients can obtainmore benefits from individualized treatment formulated by multidisciplinaryteam. Chemotherapy plus surgery might represent an alternative option for GCwith rib metastasis.展开更多
We report a case of a 49-year-old man who developed solitary rib metastasis of nasopharyngeal cancer. Patient had been treated for primary carcinoma with radiation therapy and concomitant chemotherapy. The bone metast...We report a case of a 49-year-old man who developed solitary rib metastasis of nasopharyngeal cancer. Patient had been treated for primary carcinoma with radiation therapy and concomitant chemotherapy. The bone metastasis presented as bulky, solid, painful mass in the posterior arch of 10th rib, within nine months the end of treatment. Biopsy of the solitary lesion presented the same histological characteristics as those of primary lesion. Although there are reported in literature series of nasopharyngeal cancer metastasizing to bone, we did not find previously pubfished report of a nasopharyngeal carcinoma metastasizing only to a rib.展开更多
Thymoma and thymic carcinoma are rare epithelial tumors, which originate from the thymus gland. According to the World Health Organization there are "organotypic"(types A, AB, B1, B2, and B3) and "non-o...Thymoma and thymic carcinoma are rare epithelial tumors, which originate from the thymus gland. According to the World Health Organization there are "organotypic"(types A, AB, B1, B2, and B3) and "non-organotypic"(thymic carcinomas) thymomas. Type B3 thymomas are aggressive tumors, which can metastasize. Due to the rarity of these lesions, only 7 cases of extradural metastasis are described in the literature. We report the first and unique case of a man with cervical intradural B3 thymoma metastasis. A 46-year-old man underwent thymoma surgical removal. The year after the procedure he was treated for a parietal pleura metastasis. In 2006 he underwent cervical-dorsal extradural metastasis removal and C5-Th1 stabilization. Seven years after he came to our observation complaining left cervicobrachialgia and a reduction of strength of the left arm. He underwent a cervical spine magnetic resonance imaging, which showed a new lesion at the C5-C7 level. The patient underwent a surgery for the intradural B3 thymoma metastasis. Neurological symptoms improved although the removal was subtotal. He went through postoperative radiation therapy with further mass reduction. Spinal metastases are extremely rare. To date, only 7 cases of spinal extradural metastasis have been described in the literature. This is the first case of spinal intradural metastasis. Early individuation of these tumors and surgical treatment improve neurological outcome in patients with spinal cord compression. A multimodal treatment including neoadjuvant chemotherapy, surgery and postoperative radiation therapy seems to improve survival in patients with metastatic thymoma.展开更多
We describe an uncommon case of a patient with a metastatic adenocarcinoma of ovarian origin presented as a gastric subepithelial tumor(SET) and that was diagnosed by endoscopic ultrasound fine-needle biopsy(EUS-FNB)....We describe an uncommon case of a patient with a metastatic adenocarcinoma of ovarian origin presented as a gastric subepithelial tumor(SET) and that was diagnosed by endoscopic ultrasound fine-needle biopsy(EUS-FNB). Malignant gastric lesions are rarely metastatic and the primary tumor is mainly breast, lung, esophageal cancer or cutaneous melanoma. Gastric metastasis from ovarian cancer is unusual, presenting synchronously with the primary tumor but also several years later than the initial diagnosis. From an endoscopic point of view, gastric metastasis does not present specific features. They may mimic both a primary gastric tumor or, less frequently, an SET.This case demonstrates the importance of EUS-FNB in distinguishing SETs and how this may alter treatment and prognosis.展开更多
Sternal metastases are not studied extensively in the literature. There is a paucity of information on their role in metastatic disease. The concept of the fourth column was described by Berg in 1993, and has been pro...Sternal metastases are not studied extensively in the literature. There is a paucity of information on their role in metastatic disease. The concept of the fourth column was described by Berg in 1993, and has been proven in case report, clinically and biomechanical studies. The role of the sternum as a support to the thoracic spine is well documented in the trauma patients, but not much is known about its role in cancer patients. This review examines what is known on the role of the fourth column. Following this we have identified two likely scenarios that sternal metastases may impact management:(1) sternal pathological fracture increases the mobility of the semi-rigid thorax with the loss of the biomechanical support of the sternum-rib-thoracic spine complex; and(2) a sternal metastasis increases the risk of fracture, and while being medical treated the thoracic spine should be monitored for acute kyphosis and neurological injury secondarily to the insufficiency of the fourth column.展开更多
The expression of CD44v6 and its relationship with the development, progress, invasion and metastasis of laryngeal carcinoma was investigated. The expression and content of CD44v6 mRNA in tissuess were detected by bot...The expression of CD44v6 and its relationship with the development, progress, invasion and metastasis of laryngeal carcinoma was investigated. The expression and content of CD44v6 mRNA in tissuess were detected by both RT-PCR and FCM which were respectively extracted from normal laryngeal mucosa, leukoplakia of larynx, laryngeal papilloma, polyp of vocal cord, tissues of laryngeal carcinoma, metastatic and nonmetastatic lymph nodes of neck, and tissues close to carcinoma. The outcome of RT-PCR indicated that the expression rate of CD44v6 mRNA involved in tissues of laryngeal carcinoma and metastatic lymph nodes of neck was the highest (90 %-100 %) compared with that of leukoplakia of larynx, laryngeal papilloma, tissues close to carcinoma by 0.5 cm (55.56 %-60.00 %) and that of normal laryngeal mucosa, polyp of vocal cord, nonmetastatic lymph nodes and tissues close to carcinoma by 1.0 cm was the lowest ( 13.33 %-20 %). The result from FCM was highly consistent with that from RT-PCR. It was suggested that CD44v6 was closely related with the development, progress, invasion and metastasis of laryngeal carcinoma. The outcome from the tissues close to carcinoma by different distance could do help to the determination of incisal edge in surgery abstractly.展开更多
More than 50%of prostate cancer(PCa)patients have bone metastasis with osteo-blastic lesions.MiR-18a-5p is associated with the development and metastasis of PCa,but it remains unclear whether it is involved in osteobl...More than 50%of prostate cancer(PCa)patients have bone metastasis with osteo-blastic lesions.MiR-18a-5p is associated with the development and metastasis of PCa,but it remains unclear whether it is involved in osteoblastic lesions.We first found that miR-18a-5p was highly expressed in the bone microenvironment of patients with PCa bone metastases.To address how miR-18a-5p affects PCa osteoblastic lesions,antagonizing miR-18a-5p in PCa cells or pre-osteoblasts inhibited osteoblast differentiation in vitro.Moreover,injection of PCa cells with miR-18a-5p inhibition improved bone biomechanical properties and bone mineral mass in vivo.Furthermore,miR-18a-5p was transferred to osteoblasts by exosomes derived from PCa cells and targeted the Hist1h2bc gene,resulting in Ctnnb1 up-regulation in the Wnt/β-catenin signaling pathway.Translationally,antagomir-18a-5p significantly improved bone biomechanical properties and alleviated sclerotic lesions from osteoblastic me-tastases in BALB/c nude mice.These data suggest that inhibition of exosome-delivered miR-18a-5p ameliorates PCa-induced osteoblastic lesions.展开更多
In this editorial review,we comment on the article published in the recent issue of the World Journal of Gastrointestinal Surgery.Carcinoembryonic antigen(CEA)is a fetal glycoprotein and can be secreted in very small ...In this editorial review,we comment on the article published in the recent issue of the World Journal of Gastrointestinal Surgery.Carcinoembryonic antigen(CEA)is a fetal glycoprotein and can be secreted in very small amounts from healthy adults after birth.CEA is widely used not only for diagnostic tumor markers but also importantly for the management of some gastrointestinal tumors.The most common clinical use is surveillance for the monitoring of colorectal carcinoma.However,CEA can become elevated in several malign or benign characterized pathologies.Serum CEA level may vary depending on the location of the lesion,whether it metastasizes or not,and its histopathological characteristics.It has been determined that cases with high preoperative CEA have a more aggressive course and the risk of metastasis to the lymph tissue and liver increases.In this editorial review,we focused on evaluating the role of CEA in clinical practice with a holistic approach,including the diagnostic and prognostic significance of CEA in patients with focal liver lesions,the role of CEA in follow-up after definitive surgery,and also hepatic resection for metastasis,and the management of all patients with raised CEA.展开更多
In order to enhance the performance of the CNN-based segmentation models for bone metastases, this study proposes a segmentation method that integrates dual-pooling, DAC, and RMP modules. The network consists of disti...In order to enhance the performance of the CNN-based segmentation models for bone metastases, this study proposes a segmentation method that integrates dual-pooling, DAC, and RMP modules. The network consists of distinct feature encoding and decoding stages, with dual-pooling modules employed in encoding stages to maintain the background information needed for bone scintigrams diagnosis. Both the DAC and RMP modules are utilized in the bottleneck layer to address the multi-scale problem of metastatic lesions. Experimental evaluations on 306 clinical SPECT data have demonstrated that the proposed method showcases a substantial improvement in both DSC and Recall scores by 3.28% and 6.55% compared the baseline. Exhaustive case studies illustrate the superiority of the methodology.展开更多
Objective To investigate the clinical features of several cases of malignancy with multiple bone lesions as the first manifestation.Methods Forty-nine cases of malignancy with multiple bone lesions as the first manife...Objective To investigate the clinical features of several cases of malignancy with multiple bone lesions as the first manifestation.Methods Forty-nine cases of malignancy with multiple bone lesions as the first manifestation were retrospectively analyzed from May 2018 to July 2019.All patients complained of“pain at the site of bone lesion”upon admission.Baseline patient information,such as age,gender,location of bone lesions,etiology,diagnosis method,time of onset was collected.Results The median age of the patients was 56 years old,of which 83.7%(41/49)were aged≥50 years.The median time of onset was 2 months.Among the cases,40 were confirmed as solid tumor bone metastasis,whereas the remaining 9 cases as hematological system tumor.Lung cancer and multiple myeloma were the main tumor types,accounting for 40.8%(20/49)and 16.3%(8/49),respectively.Other common causes were seven cases of cancer affecting the digestive system(three cases of liver cancer,three cases of gastric cancer,and one case of esophageal cancer),as well as seven cases of unknown primary cancer.Half of the solid tumors had only multiple bone metastases but no other distant metastasis.Conclusion Multiple bone lesions accompanied by pain may be the first clinical manifestation in various malignant tumors.The common tumor types were lung cancer,multiple myeloma,and digestive system tumor.It is more common in people aged 50 years and older.Multiple bone lesions might be the only metastasis site of some solid tumors,and its mechanism needs further investigation.展开更多
文摘Bladder tumor is the most common malignant tumor in urinary system and always com- panied with lymph node metastasis. The accurate staging plays a significant role in treatment for bladder tumor and prognostic evaluation, and the distant metastasis predicts worse prognosis. The objective of this study was to assess the clinical significance of 18F-FDG PET/CT imaging in diagnosing bladder tumor metastasis lesions. A retrospective analysis of 60 patients with bladder tumor from October 2008 to May 2010 was done. The patients were stratified based on the imaging technique. Among all 60 cases, besides the primary lesion, 81 suspected lesions were spotted and 73 confirmed as metastasis, including 50 lymph node metastases, 22 distant metastases, and 1 bone metastasis. For PET/CT imaging, its sensitivity was 94.5%, specificity 87.5%, positive predictive value 98.6%, negative predictive value 63.6% and accuracy 93.8% respectively. For CT, its sensitivity was 82.2%, specificity 50%, positive predictive value 93.8%, negative predictive value 23.5% and accuracy 79% respectively. PET/CT im- aging was superior to CT in sensitivity, specificity and accuracy. In conclusion, 18F-FDG PET/CT imaging is more significant in diagnosing bladder tumor metastasis lesions.
文摘BACKGROUND Gastric cancer (GC) with bone metastasis is rare, and rib metastasis is even lesscommon. The clinical prognosis of GC with bone metastasis is poor given the lackof an effective treatment.CASE SUMMARY A 70 year old man was referred to Shaoxing People’s Hospital with left chest painand slight dyspnea. Chest computed tomography (CT) revealed a metastaticlesion in the left 3rd rib. Esophagogastroduodenoscopy revealed several ulcers inthe angle and antrum of the stomach, and tumor biomarkers including CEA andCA-199 were clearly increased. In addition, lymph node metastasis in the lessercurvature of the stomach was identified by positron emission tomography/CTscanning. Further pathological examination confirmed metastatic adenocarcinomain the rib and medium-low differentiated adenocarcinoma in the gastric space.The patient had GC with rib metastasis, and was clinically staged as T3NxM1 (IVB).Based on multidisciplinary team opinions, the patient received five courses ofchemotherapy (CAPOX plus aptinib), and then underwent rib resection andlaparoscopic radical distal gastrectomy. The patient started four courses ofchemotherapy after surgery, and then capecitabine and aptinib were administeredorally for 3 mo. Follow-up was performed on an outpatient basis usingabdominal/chest CT and tumor biomarkers. The patient exhibited an overallsurvival greater than 2 years, and the disease-free survival was approximately 18mo. His adverse events were tolerable.CONCLUSION The incidence of GC with rib metastases is extremely low, and patients can obtainmore benefits from individualized treatment formulated by multidisciplinaryteam. Chemotherapy plus surgery might represent an alternative option for GCwith rib metastasis.
文摘We report a case of a 49-year-old man who developed solitary rib metastasis of nasopharyngeal cancer. Patient had been treated for primary carcinoma with radiation therapy and concomitant chemotherapy. The bone metastasis presented as bulky, solid, painful mass in the posterior arch of 10th rib, within nine months the end of treatment. Biopsy of the solitary lesion presented the same histological characteristics as those of primary lesion. Although there are reported in literature series of nasopharyngeal cancer metastasizing to bone, we did not find previously pubfished report of a nasopharyngeal carcinoma metastasizing only to a rib.
文摘Thymoma and thymic carcinoma are rare epithelial tumors, which originate from the thymus gland. According to the World Health Organization there are "organotypic"(types A, AB, B1, B2, and B3) and "non-organotypic"(thymic carcinomas) thymomas. Type B3 thymomas are aggressive tumors, which can metastasize. Due to the rarity of these lesions, only 7 cases of extradural metastasis are described in the literature. We report the first and unique case of a man with cervical intradural B3 thymoma metastasis. A 46-year-old man underwent thymoma surgical removal. The year after the procedure he was treated for a parietal pleura metastasis. In 2006 he underwent cervical-dorsal extradural metastasis removal and C5-Th1 stabilization. Seven years after he came to our observation complaining left cervicobrachialgia and a reduction of strength of the left arm. He underwent a cervical spine magnetic resonance imaging, which showed a new lesion at the C5-C7 level. The patient underwent a surgery for the intradural B3 thymoma metastasis. Neurological symptoms improved although the removal was subtotal. He went through postoperative radiation therapy with further mass reduction. Spinal metastases are extremely rare. To date, only 7 cases of spinal extradural metastasis have been described in the literature. This is the first case of spinal intradural metastasis. Early individuation of these tumors and surgical treatment improve neurological outcome in patients with spinal cord compression. A multimodal treatment including neoadjuvant chemotherapy, surgery and postoperative radiation therapy seems to improve survival in patients with metastatic thymoma.
文摘We describe an uncommon case of a patient with a metastatic adenocarcinoma of ovarian origin presented as a gastric subepithelial tumor(SET) and that was diagnosed by endoscopic ultrasound fine-needle biopsy(EUS-FNB). Malignant gastric lesions are rarely metastatic and the primary tumor is mainly breast, lung, esophageal cancer or cutaneous melanoma. Gastric metastasis from ovarian cancer is unusual, presenting synchronously with the primary tumor but also several years later than the initial diagnosis. From an endoscopic point of view, gastric metastasis does not present specific features. They may mimic both a primary gastric tumor or, less frequently, an SET.This case demonstrates the importance of EUS-FNB in distinguishing SETs and how this may alter treatment and prognosis.
文摘Sternal metastases are not studied extensively in the literature. There is a paucity of information on their role in metastatic disease. The concept of the fourth column was described by Berg in 1993, and has been proven in case report, clinically and biomechanical studies. The role of the sternum as a support to the thoracic spine is well documented in the trauma patients, but not much is known about its role in cancer patients. This review examines what is known on the role of the fourth column. Following this we have identified two likely scenarios that sternal metastases may impact management:(1) sternal pathological fracture increases the mobility of the semi-rigid thorax with the loss of the biomechanical support of the sternum-rib-thoracic spine complex; and(2) a sternal metastasis increases the risk of fracture, and while being medical treated the thoracic spine should be monitored for acute kyphosis and neurological injury secondarily to the insufficiency of the fourth column.
基金This project was supported by a grant from Hubei Provin-cial Natural Sciences Foundation (98J118) .
文摘The expression of CD44v6 and its relationship with the development, progress, invasion and metastasis of laryngeal carcinoma was investigated. The expression and content of CD44v6 mRNA in tissuess were detected by both RT-PCR and FCM which were respectively extracted from normal laryngeal mucosa, leukoplakia of larynx, laryngeal papilloma, polyp of vocal cord, tissues of laryngeal carcinoma, metastatic and nonmetastatic lymph nodes of neck, and tissues close to carcinoma. The outcome of RT-PCR indicated that the expression rate of CD44v6 mRNA involved in tissues of laryngeal carcinoma and metastatic lymph nodes of neck was the highest (90 %-100 %) compared with that of leukoplakia of larynx, laryngeal papilloma, tissues close to carcinoma by 0.5 cm (55.56 %-60.00 %) and that of normal laryngeal mucosa, polyp of vocal cord, nonmetastatic lymph nodes and tissues close to carcinoma by 1.0 cm was the lowest ( 13.33 %-20 %). The result from FCM was highly consistent with that from RT-PCR. It was suggested that CD44v6 was closely related with the development, progress, invasion and metastasis of laryngeal carcinoma. The outcome from the tissues close to carcinoma by different distance could do help to the determination of incisal edge in surgery abstractly.
基金supported by the National Natural Science Foundation of China(No.81930067)Key Project for Clinical Innovation of AMU(China)(No.CX2019LC107).
文摘More than 50%of prostate cancer(PCa)patients have bone metastasis with osteo-blastic lesions.MiR-18a-5p is associated with the development and metastasis of PCa,but it remains unclear whether it is involved in osteoblastic lesions.We first found that miR-18a-5p was highly expressed in the bone microenvironment of patients with PCa bone metastases.To address how miR-18a-5p affects PCa osteoblastic lesions,antagonizing miR-18a-5p in PCa cells or pre-osteoblasts inhibited osteoblast differentiation in vitro.Moreover,injection of PCa cells with miR-18a-5p inhibition improved bone biomechanical properties and bone mineral mass in vivo.Furthermore,miR-18a-5p was transferred to osteoblasts by exosomes derived from PCa cells and targeted the Hist1h2bc gene,resulting in Ctnnb1 up-regulation in the Wnt/β-catenin signaling pathway.Translationally,antagomir-18a-5p significantly improved bone biomechanical properties and alleviated sclerotic lesions from osteoblastic me-tastases in BALB/c nude mice.These data suggest that inhibition of exosome-delivered miR-18a-5p ameliorates PCa-induced osteoblastic lesions.
文摘In this editorial review,we comment on the article published in the recent issue of the World Journal of Gastrointestinal Surgery.Carcinoembryonic antigen(CEA)is a fetal glycoprotein and can be secreted in very small amounts from healthy adults after birth.CEA is widely used not only for diagnostic tumor markers but also importantly for the management of some gastrointestinal tumors.The most common clinical use is surveillance for the monitoring of colorectal carcinoma.However,CEA can become elevated in several malign or benign characterized pathologies.Serum CEA level may vary depending on the location of the lesion,whether it metastasizes or not,and its histopathological characteristics.It has been determined that cases with high preoperative CEA have a more aggressive course and the risk of metastasis to the lymph tissue and liver increases.In this editorial review,we focused on evaluating the role of CEA in clinical practice with a holistic approach,including the diagnostic and prognostic significance of CEA in patients with focal liver lesions,the role of CEA in follow-up after definitive surgery,and also hepatic resection for metastasis,and the management of all patients with raised CEA.
文摘In order to enhance the performance of the CNN-based segmentation models for bone metastases, this study proposes a segmentation method that integrates dual-pooling, DAC, and RMP modules. The network consists of distinct feature encoding and decoding stages, with dual-pooling modules employed in encoding stages to maintain the background information needed for bone scintigrams diagnosis. Both the DAC and RMP modules are utilized in the bottleneck layer to address the multi-scale problem of metastatic lesions. Experimental evaluations on 306 clinical SPECT data have demonstrated that the proposed method showcases a substantial improvement in both DSC and Recall scores by 3.28% and 6.55% compared the baseline. Exhaustive case studies illustrate the superiority of the methodology.
文摘Objective To investigate the clinical features of several cases of malignancy with multiple bone lesions as the first manifestation.Methods Forty-nine cases of malignancy with multiple bone lesions as the first manifestation were retrospectively analyzed from May 2018 to July 2019.All patients complained of“pain at the site of bone lesion”upon admission.Baseline patient information,such as age,gender,location of bone lesions,etiology,diagnosis method,time of onset was collected.Results The median age of the patients was 56 years old,of which 83.7%(41/49)were aged≥50 years.The median time of onset was 2 months.Among the cases,40 were confirmed as solid tumor bone metastasis,whereas the remaining 9 cases as hematological system tumor.Lung cancer and multiple myeloma were the main tumor types,accounting for 40.8%(20/49)and 16.3%(8/49),respectively.Other common causes were seven cases of cancer affecting the digestive system(three cases of liver cancer,three cases of gastric cancer,and one case of esophageal cancer),as well as seven cases of unknown primary cancer.Half of the solid tumors had only multiple bone metastases but no other distant metastasis.Conclusion Multiple bone lesions accompanied by pain may be the first clinical manifestation in various malignant tumors.The common tumor types were lung cancer,multiple myeloma,and digestive system tumor.It is more common in people aged 50 years and older.Multiple bone lesions might be the only metastasis site of some solid tumors,and its mechanism needs further investigation.