Effectiveness of Intraoperative Cell Salvage Combined with a Modified Leucocyte Depletion Filter in Metastatic Spine Tumour Surgery

Background To compare the effectiveness of intraoperative cell salvage (IOCS) combined with a modified leucocyte depletion filter (MLDF) with IOCS combined with a regular leucocyte depletion filter (RLDF) in eliminating tumour cells from blood salvage during metastatic spine tumour surgery (MSTS). Methods Patients with a known primary epithelial tumour who underwent MSTS were recruited for this study. Blood samples were collected in 5 stages: from the patients’ vein before anaesthesia induction (S1), from the operative field during tumour manipulation (S2), and from the operative blood after IOCS processing (S3) and after IOCS+RLDF (S4) and IOCS+MLDF (S5) processing. The polyploids of tumour cells in the blood samples were collected and counted with immunomagnetic separation enrichment and fluorescence in situ hybridization. Results We recruited 20 patients. Tumour cells were detected in 14 patients (70%) in S1, 16 patients (80%) in S2, 13 patients (65%) in S3, and 12 patients (60%) in S4. MLDF was added in 8 patients. Tumour cells were detected in only 1 of 8 patients in S5 (12.5%). There were significantly fewer tumour cells in the samples collected after MLDF processing (S5) than in the samples collected after RLDF (S4) and around the tumour (S2) (P = 0.016 and P = 0.039, respectively). Although no significant difference was observed between S4 and S1, a downward trend was observed after IOCS+RLDF processing. Conclusions Tumour cells could be removed by IOCS combined with RLDF from blood salvaged during MSTS, but residual tumour cells remained. The findings support the notion that MLDF eliminates tumour cells more effectively than RLDF. Hence, this technique can be applied to MSTS. Trial Registration ChiCTR1800016162 Chinese Clinical Trial Registry http://www.chictr.org.cn/showproj.aspx?proj=27263

Evaluation of the Feasibility of Transfusing Leucocyte Depletion Filter (LDF) Processed Intra-Operative Cell Salvage (IOCS) Blood in Metastatic Spine Tumour Surgery (MSTS): Protocol for a Non Randomised study (Preprint)

BACKGROUND Metastatic Spine Tumour Surgery (MSTS) is often complex and extensive leading to significant blood loss. Allogeneic blood transfusion (ABT) is mainstay of blood replenishment but with immune-mediated post-operative complications. Alternative blood management techniques (salvaged blood transfusion (SBT)) allow us to overcome such complications. Despite widespread use of intra-operative cell salvage (IOCS) in oncological and non-oncological surgeries, surgeons remain reluctant to employ IOCS in MSTS. OBJECTIVE This study will analyse the safety of IOCS-LDF processed blood transfusion to patients undergoing MSTS by assessing clinical outcomes – disease progression: tumour progression and overall survival (OS). We will also evaluate whether reinfusion of IOCS-LDF processed blood can reduce the ABT rates in patients undergoing MSTS by comparing the proportion of MSTS patients requiring ABT in those patients who consent to receive SBT, and those who do not consent for SBT. METHODS We aim to recruit 90-patients (minimum)-30 SBT, 30 ABT and 30 with no blood transfusion (NBT). SBT and ABT form the two experimental arms, while NBT forms the control cohort. All available patient data will be reviewed to determine tumour burden secondary to metastasis and post-operative survival and/or disease progression, improvement in pain, neurology and ambulatory status. Collected data will be studied at 3, 6, 12 and 24 months post-operatively, or until demise, whichever occurs first. Collected outcomes of the experimental groups will be compared with that of the control group. Statistical Analysis: Outcomes will be analysed using one-way ANOVA and Fisher’s exact test. OS will be studied by Kaplan-Meier curve and log rank test. Multivariate and competing risk analysis will be used to study the association between blood transfusion type and tumour progression. All statistical analyses will be done using STATA/SE14.0 RESULTS This is the first clinical study on the use of IOCS in MSTS from various primary malignancies. It will provide major clinical evidence regarding safety and applicability of IOCS in MSTS. It will help reduce ABT usage; thus improving overall blood management of MSTS patients. However, limitation of this study is that not all patients undergoing MSTS will survive for the total follow-up period (two years), thereby theoretically leading to under-reporting of disease progression. CONCLUSIONS Results will be disseminated via peer-reviewed publications and will pave the way for future studies CLINICALTRIAL This study did not involve a healthcare intervention and hence, did not need to be registered