Impact of International Standardization of Alkaline Phosphatase Assay on Prognostic Prediction by Prognosis in Palliative care Study predictor (PiPS) Models

ABSTRACT

Alkaline phosphatase (ALP) has been measured using a Japan-specific method in Japan. However, the Japan Society of Clinical Chemistry (JSCC) has decided to change to an international standardized method of International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) by the end of fiscal year 2020. The Prognosis in Palliative care Study predictor (PiPS) models were the prognosis predictor methods developed in the UK. The ALP value is included in the test items of PiPS-B of the PiPS models. The international standardization method was not used in previous reports about PiPS in Japan. In this study, we investigated the effect of changing measurement methods of ALP levels on the prognostic value of PiPS using IFCC conversion values. We performed prognostic prediction by PiPS models in 239 consecutive patients admitted to our palliative care unit from March 2019 to March 2021. In 98 PiPS-B calculated patients, the prognosis was recalculated by replacing ALP values with the JSCC recommended conversion values. 5 of 98 patients whose prognosis was “weeks” changed to “months+”. It was suggested that a change in the method of ALP measurement from JSCC to IFCC method may change the “weeks” prognosis prediction by PiPS to a “months+”.