Editorial series: cancer care in low- and middle-income countries

Ureteral involvement by metastatic malignant disease Abstract Ureteral metastases from other primary cancers are very rare. Treatment of these metastases is difficult and outcomes are poor. A thorough literature review was done with the aim of finding characteristics that may influence survival rates of patients with ureteral metastases. Systematic literature searches of PubMed and Web of Science were performed in Jan 2019. A total of 79 papers that included 265 patients with cancer metastases to their ureters were finally considered for evidence synthesis. Prostate, bladder, breast, gut cancer and lymphoma were the predominant primary tumors. The median interval time from primary tumor diagnosis to ureter metastasis was 28.5 months. The median survival time after diagnosis of ureter metastasis was 18 months. Risk factors of survival were analyzed. Age, sex, hydronephrosis, ureter side, and segment were not associated with survival. Interval time and treatment were associated with overall survival. Further analysis indicated that patients who underwent surgery had better outcomes.

NHE5 regulates growth factor signaling, integrin trafficking, and degradation in glioma cells Abstract Na+/H+ exchanger 5 (NHE5) is enriched in neurons and cycles between recycling endosomes and plasma membranes and transports protons to the endosomal lumen as well as to the extracellular space. Although NHE5 expression is undetectable in normal astrocytes, C6 glioma cells express NHE5 at an elevated level. Using C6 cells as a model, here we demonstrate that NHE5 has an important role in tumor growth and tumor cell proliferation and invasion. Glioma xenografts originating from NHE5-knockdown cells exhibited significantly slower growth than those from NHE1-knockdown cells and control cells. Histological characterization of the migration front of NHE5-knockdown tumors revealed a less invasive and less proliferative appearance than NHE1-knockdown and control tumors. NHE5-knockdown but not NHE1-knockdown led to downregulation of fetal bovine serum (FBS)-induced MET and EGFR signaling. Moreover, depletion of NHE5 but not NHE1 reduced the ability of cells to spread on collagen. We found that NHE5 depletion greatly abrogated endocytic recycling and the protein stability of β1-integrin, which in part accounted for the defective cell adhesion, spreading, and invasion of NHE5-knockdown cells.

Retrospective analysis by site of primary tumor of patients with unresectable locally-advanced or metastatic pancreatic adenocarcinoma receiving chemotherapy Abstract The primary tumor site of pancreatic cancer has been suggested as a recommended variable in future studies of treatments of patients with unresectable or metastatic pancreatic adenocarcinoma (mPDAC). The aim of the current study is to analyze the differences between mPDAC of the head and mPDAC of the body-tail, both in prognostic and predictive terms in patients with mPDAC receiving palliative chemotherapy. Data of patients with a diagnosis of mPDAC and receiving chemotherapy (CHT), registered in the database of the division of Medical Oncology of the Ospedale Civile di Sanremo, were analyzed. Thirty-two variables were extracted, and their relationship with primary tumor site and outcome were analyzed. One hundred twenty-nine patients were eligible. The characteristics of patients were different between those with the primary tumor of the pancreatic head or body-tail. After construction of two Cox models, two prognostic factors (the number of CHT lines, the neutrophil reduction after one cycle of CHT) were identified as independent among mPDAC of the head, while only one variables (the number of drugs in the CHT regimen) predicted the outcome of patients with body-tail tumors; after statistical correction for false discovery rate, all the three variables maintained their significant relationship with OS. Despite a similar overall survival among parients with tumors of the head compared to those with tumors of body-tail, a very different disease course was reported, with different prognostic and predictive variables.

Metastatic dissemination patterns of different primary tumors to the spine and other bones Abstract Metastatic spine disease (MSD) is a severe event in cancer patients. Experimental data indicate that bone metastasis is mostly mediated by blood flow-dependent, passive arrest of circulating tumor cells to the bone metastatic niche (BMN). Here, we have set out to test these experimental observations in a clinical, human setting to improve our understanding of MSD. 507 patients, treated on spinal metastases in our institution from 2005 to  2015 were retrospectively evaluated. We identified 259 patients with accessible staging reports of the skeleton before and at initial diagnosis of MSD. Data analysis comprised localizations of bone metastases, underlying malignancy and time to development of MSD. Dissemination pattern of bone metastasis was correlated with red bone marrow (RBM) content of the respective bone as a measure of blood flow. Spinal metastases occurred most frequently in lung cancer (21%), prostate cancer (19%), and breast cancer (12%). At the diagnosis of MSD, majority of patients have multiple extra-spinal bone metastases (2/3). The distribution of metastases to extra-spinal bones and to the spine is mostly proportional to the RBM content of the involved bone. Corresponding to the high RBM content, thoracic spine, pelvic bones and ribs represent a predilection site for bone metastasis. We confirm a distinct preference of cancer types to metastasize to bones. When it comes to bone metastases all primaries show uniform distribution pattern, which supports the hypothesis of a predominantly blood flow-dependent distribution of tumor cells and passive arrest to the BMN rather than a spine-specific homing mechanism.

Identification of inflammatory mediators associated with metastasis of oral squamous cell carcinoma in experimental and clinical studies: systematic review Abstract Metastasis, whether regional or distant, remains the main cause of morbidity and recurrence in oral cancer. The accumulating evidence suggests that inflammatory mediators are strong drivers for cancer progression and spread. However, the precise role of these inflammatory mediators in mediating specific metastatic stage is poorly understood due to lack of integration/validation of experimental research data and the clinical trials, i.e., the data produced from research is not translated to clinical therapeutic targets. This, in turn, results in the lack of developing reliable biomarker that can be used for accurate diagnosis/prognosis of the tumour spread. We have performed a systematic review to assess the role of inflammatory mediators as potential markers for diagnosis/prognosis of oral squamous cell carcinoma (OSCC) metastasis. We carried out a systematic search the PubMed, Web of Science, Embase and Scopus databases under the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Australian National Health and Medical Research Council (NHMRC). Articles were divided into two groups; experimental (in-vivo) and clinical studies. The REporting recommendations for tumour MARKer prognostic studies Scale (REMARK) was used to assess the quality of the studies for the clinical search while Animal research: Reporting In-vivo experiments (ARRIVE) guidelines were used to assess the quality of the animal studies. Sixteen articles in the clinical group and four articles in the experimental group were included in the final review. We identified nine inflammatory mediators; CXCR4, CXCL12 (SDF-1), CCR7, IL-6, IL-18, CCL20 (MIP-3), CXCL1 (GRO-1), CCL3, CXCR2. This panel of inflammatory mediators can provide a framework for hypothesis testing of the potential value of these mediators in metastatic prognosis. We recommend carrying a large cohort study with data pooling for adequate assessment and testing of the inflammatory panel of mediators.

Breast cancer cells expressing cancer-associated sialyl-Tn antigen have less capacity to develop osteolytic lesions in a mouse model of skeletal colonization Abstract Breast cancer is one of the most prevalent malignancies in women, and approximately 75–80% of patients with advanced breast cancer develop bone metastasis. Expression of the cancer-associated carbohydrate antigen sialyl-Tn (STn) in breast cancer is associated with a poor prognosis; however, involvement of STn in the development of metastatic bone lesions remains unclear. We investigated whether STn expression on breast cancer cells influences intraosseous tumor growth and bone response in mice models of skeletal colonization. STn-positive (STn+) breast cancer cells were generated by stable transfection of an expression vector encoding ST6GaLNAc I into the breast cancer cell line MDA-MB-231. Parental MDA-MB-231 cells not expressing STn antigen were used as STn-negative (STn−) breast cancer cells. Contrary to expectations, STn expression attenuated the development of destructive bone lesions in the in vivo mice models. An in vitro study demonstrated that STn expression impaired adhesion of MDA-MB-231cells to bone marrow stromal cells. This finding in vitro was also confirmed by another breast cancer cell line MCF-7. Cell adhesion to fibronectin and type I collagen was also impaired in STn+ MDA-MB-231 cells compared to that in STn− MDA-MB-231 cells, suggesting integrin dysfunction. Given that the integrin β1 subunit is the main carrier of the STn epitope, it is likely that changes in glycan structure impaired the adhesive capacity of β1 integrin in the bone environment, leading to attenuation of tumor cell engraftment. In conclusion, breast cancer cells expressing STn antigen had less capacity for skeletal colonization, possibly due to impaired adhesive capability.

Intraperitoneal mitomycin C improves survival compared to cytoreductive surgery alone in an experimental model of high-grade pseudomyxoma peritonei Abstract Pseudomyxoma peritonei (PMP) is a rare cancer commonly originating from appendiceal neoplasms that presents with mucinous tumor spread in the peritoneal cavity. Patients with PMP are treated with curative intent by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). The value of adding HIPEC to CRS has not been proven in randomized trials, and the objective of this study was to investigate the efficacy of intraperitoneal mitomycin C (MMC) and regional hyperthermia as components of this complex treatment. Xenograft tissue established from a patient with histologically high-grade PMP with signet ring cell differentiation was implanted intraperitoneally in 65 athymic nude male rats and the animals were stratified into three treatment groups; the cytoreductive surgery group (CRSG, CRS only), the normothermic group (NG, CRS and intraperitoneal chemotherapy perfusion (IPEC) with MMC at 35 ºC), and the hyperthermic group (HG, CRS and IPEC at 41 ºC). The main endpoints were survival and tumor weight at autopsy. Adequate imitation of the clinical setting and treatment approach was achieved. The median survival was 31 days in the CRSG, 60 days in NG and 67 days in HG. The median tumor weights at autopsy were 34 g in CRSG, 23 g NG and 20 g in HG. In conclusion, the addition of IPEC with MMC after CRS doubled the survival time and reduced tumor growth compared to CRS alone. Adding regional hyperthermia resulted in a modest improvement of treatment outcome.

Disparities in the use of stereotactic radiosurgery for the treatment of lung cancer brain metastases: a SEER-Medicare study Abstract Stereotactic radiosurgery (SRS) is a costly procedure used to irradiate disease tissue while sparing healthy tissue, ideally limiting the side effects of treatment. SRS is frequently used in the setting of lung cancer, which is associated with greater rates of BM, though its cost may lead to potentially inequitable use across patient populations. This study investigates potential disparities in the use of SRS to treat Medicare patients. Surveillance, Epidemiology, and End-Results cancer registry data for patients diagnosed between the years 2010 and 2012 were examined to identify lung cancer patients diagnosed with BM at the same time as their primary cancer (SBM). Medicare claims for SRS were identified; the odds of having SRS claims and hazards of mortality associated with those odds were examined with respect to various clinical and demographic characteristics. Of 74,142 Medicare-enrolled patients diagnosed with lung cancer, 9192 were diagnosed with SBM and 3259 of those patients received SRS. Adjusting for clinical and demographic characteristics, males with SBM had 0.85 times the odds of SRS compared to females with SBM. Black patients and those of other race had significantly lower odds of evidence of SRS compared to WNH patients. SRS may not be delivered equitably among Medicare patients. Males and minority patients may have decreased odds of SRS and worse survival compared to female and WNH patients, respectively.

Repeated stereotactic radiosurgery (SRS) using a non-coplanar mono-isocenter (HyperArc™) technique versus upfront whole-brain radiotherapy (WBRT): a matched-pair analysis Abstract Stereotactic radiosurgery (SRS) is an effective treatment option for multiple brain metastases (BMs). Modern mono-isocentric techniques allow the delivery of multiple stereotactic courses, in the event of intracranial failure. Nevertheless, limited data on effectiveness and toxicity have been reported in comparison to WBRT. Aim of this retrospective matched-pair analysis was to compare patients affected by limited BMs treated with multiple SRS courses using a mono-isocentric, non-coplanar technique (HyperArc™, Varian Medical System) to upfront WBRT. One hundred and two patients accounting for 677 BMs were treated with HyperArc™. In case of further intracranial progression, 44 treatment courses of 201 metastases in 19 patients, were treated by subsequent HyperArc™ courses. This population was matched with 38 patients treated with WBRT. The median BMs number was 4 (range 2–10) for HyperArc™ and 5 (range 2–10) for WBRT. Overall survival (OS) and toxicity were evaluated. The median follow-up was 9 months (range 3–40 months). The median OS was not reached (range 5–22 months) for HyperArc™ patients and 8 months (range 3–40 months) for WBRT patients, while the 1-year OS was 77% and 34.6% for HyperArc™ and WBRT, respectively (p = 0.001; HR 4.77, 95% CI 1.62–14.00). There was one case of radionecrosis. HyperArc™ is an effective and safe technique for the treatment of multiple BMs. In selected cases of intracranial oligorecurrence, further subsequent courses can be safely delivered with the same technical approach. Moreover, in patients with a limited number of BMs, SRS showed an improved survival outcome when compared to WBRT.