Quality Control of Breast Cancer Surgery Samples: Introducing Time Stamp Checking.

Background: Analytical information obtained from clinical tissue samples has recently become more important due to recent advancements in the clinical practice of medicine, for example, gene panel testing. However, acquiring and managing the sample quality, which greatly influences the analyses, are not sufficient and hence requires immediate attention. We introduced time stamp (TS) recording and documentation using the Standard PREanalytical Code (SPREC) for breast cancer surgery samples to monitor and control their quality. Materials and Methods: The TS recording used SPREC for quality control of each sample by recording seven factors: type of sample, type of collection, warm ischemia time (WIT), cold ischemia time (CIT), fixation type, fixation time (FT), and long-term storage. The responsibilities to record each factor were assigned among group members (breast surgeons, anesthesiologists, pathologists, operating room nurses, and medical technologists in pathology). Results: Records based on SPREC were recorded for 393 surgical cases of first-time breast cancer patients performed at the Kanagawa Cancer Center from May 2018 to April 2019. The vascular clamp time was defined as when skin flap formation was completed, regardless of the surgical procedure. An anesthesiologist recorded the vascular clamp time and sample collection time, and the pathologist recorded the fixation start time and fixation end time. WIT was 23 (3-116) minutes (breast-conserving surgery, 11 [3-38] minutes; mastectomy, 26 [5-116] minutes; and nipple-sparing mastectomy, 39 [31-43] minutes), CIT was 37 (3-1052) minutes, and FT was 43 (17-115) hours. The median CIT and FT were significantly shortened after introducing the TS system, and the variabilities were reduced. Conclusion: A TS system for quality control of breast cancer surgical sample functions well due to the establishment of highly versatile WIT and a working group consisting of multiple members of different occupations who shared roles.