Risk factors for blood transfusion and its prognostic implications in curative gastrectomy for gastric cancer.

BACKGROUND: Gastric cancer (GC) is still a prevalent neoplasm around the world and its main treatment modality is surgical resection. The need for perioperative blood transfusions is frequent, and there is a long-lasting debate regarding its impact on survival. AIM: To evaluate the factors related to the risk of receiving red blood cell (RBC) transfusion and its influence on surgical and survival outcomes of patients with GC. METHODS: Patients who underwent curative resection for primary gastric adenocarcinoma at our Institute between 2009 and 2021 were retrospectively evaluated. Clinicopathological and surgical characteristics data were collected. The patients were divided into transfusion and non-transfusion groups for analysis. RESULTS: A total of 718 patients were included, and 189 (26.3%) patients received perioperative RBC transfusion (23 intraoperatively, 133 postoperatively, and 33 in both periods). Patients in the RBC transfusions group were older (P < 0.001), and had more comorbidities (P = 0.014), American Society of Anesthesiologists classification III/IV (P < 0.001), and lower preoperative hemoglobin (P < 0.001) and albumin levels (P < 0.001). Larger tumors (P < 0.001) and advanced tumor node metastasis stage (P < 0.001) were also associated with the RBC transfusion group. The rates of postoperative complications (POC) and 30-d and 90-d mortality were significantly higher in the RBC transfusion group than in the non-transfusion group. Lower hemoglobin and albumin levels, total gastrectomy, open surgery, and the occurrence of POC were factors associated with the RBC transfusion. Survival analysis demonstrated that the RBC transfusions group had worse disease-free survival (DFS) and overall survival (OS) compared with patients who did not receive transfusion (P < 0.001 for both). In multivariate analysis, RBC transfusion, major POC, pT3/T4 category, pN+, D1 lymphadenectomy, and total gastrectomy were independent risk factors related to worse DFS and OS. CONCLUSION: Perioperative RBC transfusion is associated with worse clinical conditions and more advanced tumors. Further, it is an independent factor related to worse survival in the curative intent gastrectomy setting.

A new strategy to identify rare blood donors: single polymerase chain reaction multiplex SNaPshot reaction for detection of 16 blood group alleles.

BACKGROUND: As an alternative to phenotyping, large-scale DNA-based assays, which are feasible for high-throughput donor red blood cell typing, were developed for determination of blood group polymorphisms. However, high-throughput genotyping platforms based on these technologies are still expensive and the inclusion of single nucleotide polymorphisms and analysis of the alleles depend on the manufacturer's determination. To overcome this limitation and in order to develop an assay to enable the screening of rare donors, we developed a SNaPshot assay for analysis of nine single nucleotide polymorphisms related to antigens that are difficult to assess using conventional serology. MATERIALS AND METHODS: The single polymerase chain reaction multiplex SNaPshot reaction was optimized to identify nine single nucleotide polymorphisms determining 16 alleles: KEL*3/KEL*4, KEL*6/KEL*7, DI*1/DI*2, DI*3/DI*4, YT*1/YT*2, CO*1/CO*2, DO*1/DO*2, DO*4, DO*5. We designed a single multiplex PCR with primers encompassing the blood group single nucleotide polymorphisms and performed an internal reaction with probe primers able to discriminate the alleles after fragment analysis. The SNaPshot assay was validated with 140 known alleles previously determined by PCR restriction fragment length polymorphism. RESULTS: We were able to simultaneous detect nine single nucleotide polymorphisms defining 16 blood group alleles on an assay based on a multiplex PCR combined with a single base extension using genomic DNA. DISCUSSION: This study demonstrates a robust genotyping strategy for conducting rare donor screening which can be applied in blood centers and could be an important tool for identifying antigen-negative donors and, therefore, for providing rare blood.

Magnetic bead technology for viral RNA extraction from serum in blood bank screening

Nucleic acid amplification testing (NAT) was recently recommended by Brazilian legislation and has been implemented at some blood banks in the city of São Paulo, Brazil, in an attempt to reduce blood-born transmission of human immunodeficiency virus (HIV) and hepatitis C virus. OBJECTIVE: Manual magnetic particle-based extraction methods for HIV and HCV viral nucleic acids were evaluated in combination with detection by reverse transcriptase - polymerase chain reaction (RT-PCR) one-step. METHODS: Blood donor samples were collected from January 2010 to September 2010, and minipools of them were submitted to testing. ELISA was used for the analysis of anti-HCV/HIV antibodies. Detection and amplification of viral RNA was performed using real-time PCR. RESULTS: Out of 20.808 samples screened, 53 samples (29 for HCV and 24 for HIV) were confirmed as positive by serological and NAT methods. CONCLUSION: The manual magnetic bead-based extraction in combination with real-time PCR detection can be used to routinely screen blood donation for viremic donors to further increase the safety of blood products.

Magnetic bead technology for viral RNA extraction from serum in blood bank screening.

UNLABELLED: Nucleic acid amplification testing (NAT) was recently recommended by Brazilian legislation and has been implemented at some blood banks in the city of São Paulo, Brazil, in an attempt to reduce blood-born transmission of human immunodeficiency virus (HIV) and hepatitis C virus. OBJECTIVE: Manual magnetic particle-based extraction methods for HIV and HCV viral nucleic acids were evaluated in combination with detection by reverse transcriptase - polymerase chain reaction (RT-PCR) one-step. METHODS: Blood donor samples were collected from January 2010 to September 2010, and minipools of them were submitted to testing. ELISA was used for the analysis of anti-HCV/HIV antibodies. Detection and amplification of viral RNA was performed using real-time PCR. RESULTS: Out of 20.808 samples screened, 53 samples (29 for HCV and 24 for HIV) were confirmed as positive by serological and NAT methods. CONCLUSION: The manual magnetic bead-based extraction in combination with real-time PCR detection can be used to routinely screen blood donation for viremic donors to further increase the safety of blood products.