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《Clinical breast cancer》2022,22(6):507-514
Breast cancer (BC) is a highly metastatic, pathological cancer that significantly affects women worldwide. The mortality rate of BC is related to its heterogeneity, aggressive phenotype, and metastasis. Recent studies have highlighted that the tumor microenvironment (TME) is critical for the interplay between metastasis mediators in BC. BC stem cells, tumor-derived exosomes, circulatory tumor cells (CTCs), and signaling pathways dynamically remodel the TME and promote metastasis. This review examines the cellular and molecular mechanisms governing the epithelial to mesenchymal transition (EMT) that facilitate metastasis. This review also discusses the role of cancer stem cells (CSCs), tumor-derived exosomes, and CTs in promoting BC metastasis. Furthermore, the review emphasizes major signaling pathways that mediate metastasis in BC. Finally, the interplay among CSCs, exosomes, and CTCs in mediating metastasis have been highlighted. Therefore, understanding the molecular cues that mediate the association of CSCs, exosomes, and CTCs in TME helps to optimize systemic therapy to target metastatic BC.  相似文献   
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Breast cancer has the highest incidence rate of malignancy in women worldwide. A major clinical challenge faced by patients with breast cancer treated by conventional therapies is frequent relapse. This relapse has been attributed to the cancer stem cell (CSC) population that resides within the tumor and possess stemness properties. Breast CSCs are generated when breast cancer cells undergo epithelial-mesenchymal transition resulting in aggressive, highly metastatic, and invasive phenotypes that exhibit resistance towards chemotherapeutics. Metastasis, a phenomenon that aids in the migration of breast CSCs, occurs through any of three different routes: hematogenous, lymphatic, and transcoelomic. Hematogenous dissemination of breast CSCs leads to metastasis towards distant unrelated organs like lungs, liver, bone, and brain causing secondary tumor generation. Activation of metastasis genes or silencing of metastasis suppressor genes often leads to the advancement of metastasis. This review focuses on various genes and molecular factors that have been implicated to regulate organ-specific breast cancer metastasis by defying the available therapeutic interventions.  相似文献   
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Parotid lymph node (PLN) metastasis greatly worsens the prognosis of patients with oral squamous cell carcinoma (OSCC) and poses a great challenge for further treatment of OSCC. The clinicopathological characteristics and treatment strategies for PLN metastasis from OSCC need to be comprehensively elucidated. A retrospective review of OSCC patients who experienced postoperative PLN metastasis in our department between 2000 and 2018 was performed in this study. A total of 47 OSCC patients with postoperative PLN metastasis were identified. PLN with metastasis were divided into three groups based on the location: parotid tail (PLN-t), superficial lobe (PLN-sl), and deep lobe (PLN-dl). Most of the patients experienced PLN metastasis within less than 12 months after the primary surgery for OSCC. Comparatively, patients with PLN-sl metastasis were more prone to have infiltration of the facial nerve. The tongue and buccal mucosa were the most frequent primary sites associated with PLN metastasis from OSCC. PLNs in the parotid tail were most commonly affected by the metastasized OSCC. Consequently, we recommend a series of strategies for the prevention and treatment of PLN metastasis for OSCC patients. In conclusion, PLNs should not be overlooked during preoperative evaluation and postoperative follow-up examinations for OSCC patients.  相似文献   
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BackgroundMost studies exploring the role of staging laparoscopy in gastric cancer are limited by low sample size and are predominantly conducted in Asian countries. This study sets out to determine the value of staging laparoscopy in patients with advanced gastric cancer in a Western population.MethodsAll patients with gastric cancer from a tertiary referral center without definite evidence of non-curable disease after initial staging, and who underwent staging laparoscopy between 2013 and 2020, were identified from a prospectively maintained database. The proportion of patients in whom metastases or locoregional non-resectability was detected during staging laparoscopy was established. Secondary outcomes included the avoidable surgery rate (detection of non-curable disease during gastrectomy with curative intent) and diagnostic accuracy (sensitivity, specificity, accuracy, negative and positive predictive value).ResultsA total of 216 patients were included. Staging laparoscopy revealed metastatic disease in 46 (21.3 %) patients and a non-resectable tumor in three (1.4 %) patients. During intended gastrectomy, non-curable disease was revealed in 13 (8.6 %) patients. Overall sensitivity, specificity and diagnostic accuracy were 76.6 %, 100 % and 92.6 %, respectively. The positive predictive value was 100 % and the negative predictive value was 90.3 %.ConclusionStaging laparoscopy is valuable in the staging process of gastric cancer with a high accuracy in detecting non-curable disease, thereby preventing futile treatment and its associated burden.  相似文献   
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PurposeTo examine the annual hospital volume of surgery in relation to survival in colorectal cancer. Previous studies on hospital volume and survival following colorectal cancer surgery are conflicting.MethodsAll 49 032 patients who underwent resection for colorectal cancer in 1987–2016 in Finland were included, with complete follow-up until December 31, 2019. Primary outcome was 5-year mortality. Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI) for quartiles of annual hospital volume for colorectal surgery, adjusted for calendar period, age, sex, comorbidity, stage, tumor location and oncological therapy. Additionally, colon and rectal cancer surgery were assessed separately. Sensitivity analysis of patients with confirmed curative intent was conducted.ResultsCompared to highest quartile (≥108 resections annually), lowest hospital volume (≤37 resections annually) was associated with slightly increased 5-year all-cause mortality (adjusted HR 1.07, 95% CI 1.02–1.12). A pre-planned subgroup-analysis suggested a slightly improved 5-year survival in high-volume institutions for rectal cancer, but not colon cancer surgery. Sensitivity analysis including only those operated with confirmed curative intent suggested no differences between hospital volume groups in colorectal, colon or rectal cancer for 5-year all-cause mortality.ConclusionHigher hospital volume is associated with slightly improved all-cause 5-year mortality in colorectal cancer surgery, but this effect may be limited to rectal cancer surgery only. Volume-outcome relationship in rectal cancer surgery should be investigated further using large datasets. These results do not support centralization of colon cancer surgery based on hospital volume only.  相似文献   
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Intravascular papillary endothelial hyperplasia or Masson's tumour is a non-neoplastic vascular lesion of reactive character. It is a rare diagnosis, clinically non-specific and with diverse locations. It is essential to take it into consideration and make a differential diagnosis with malignant vascular tumours such as angiosarcoma. Pathological study is fundamental for diagnosis. Treatment consists of complete resection of the tumour, including sufficiently wide margins to avoid recurrence.The case reported is an exceptional event, because of the pelvic location of the Masson's tumour that was diagnosed as part of the surgical staging of an ovarian cancer.  相似文献   
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