Analysis of Platelet Count and New Cancer Diagnosis Over a 10-Year Period

Abstract

IMPORTANCE Individuals with cancer often have an elevated platelet count at the time of diagnosis.The extent to which an elevated platelet count is an indicator of cancer is unclear.OBJECTIVE To evaluate the association of an elevated platelet count with a cancer diagnosis. DESIGN, SETTING, AND PARTICIPANTSThis nested case-control study included Ontario residents enrolled in the provincial health insurance plan who had 1 or more routine complete blood count (CBC) tests performed between January 1, 2007, and December 31, 2017, with follow-up through December 31, 2018. Case patients were individuals with a new cancer diagnosis during the observation period. Eligible control individuals were cancer free before the date of diagnosis for a case patient to whom they were matched. One case patient was matched to 3 controls based on sex, age, and health care use patterns. Data were analyzed from September 24, 2020, to July 13, 2021.EXPOSURES Case patients and controls were assigned to 1 of 5 exposure groups based on age-and sex-specific platelet count distributions in the control population: very low (Յ10th percentile), low (>10th to 25th percentile), medium (>25th to <75th percentile), high (75th to <90th percentile), and very high (Ն90th percentile). MAIN OUTCOMES AND MEASURESOdds ratios (ORs) were estimated for specific cancer sites for each category of platelet count at intervals up to 10 years after a blood test. RESULTSOf the 8 917 187 eligible Ontario residents with a routine CBC record available, 4 971 578 (55.8%) were women; the median age at the first CBC was 46.4 years (IQR, 32.5-59.5 years). Among individuals with a routine CBC record available, 495 341 (5.6%) received a diagnosis of first primary cancer during the 10-year observation period. The OR for a solid tumor diagnosis associated with a very high platelet count vs a medium platelet count in the 6-month period before the diagnosis was 2.32 (95% CI, 2.28-2.35). A very high platelet count was associated with colon (OR, 4.38; 95% CI, lung (OR, 4.37; 95% CI, ovarian (OR, 4.62; 95% CI,, and stomach (OR, 4.27; 95% CI, 3.91-4.66) cancers. Odds ratios attenuated with increasing time from CBC test to cancer diagnosis. CONCLUSIONS AND RELEVANCEIn this nested case-control study, an elevated platelet count was associated with increased risk of cancer at several sites. Our findings suggest that an elevated platelet count could potentially serve as a marker for the presence of some cancer types.

Development and Validation of a nomogram for forecasting survival of alcohol related hepatocellular carcinoma patients

“…The inflammatory process and the presence of oxidative stress secondary to cancer may contribute to the level of RDW. Patients with malignant tumor often have an elevated platelet counts (38). In a nested case-control study, an elevated platelet count was associated with increased risk of cancer at several sites (38).…”

“…Patients with malignant tumor often have an elevated platelet counts (38). In a nested case-control study, an elevated platelet count was associated with increased risk of cancer at several sites (38). A large retrospective study (39) shows that lower PLT is associated with better outcomes in patients with advanced HCC.…”

Platelet detection as a new liquid biopsy tool for human cancers

“…In a large cohort study of Chinese Taipei population, both low and high platelet count in older cancer patients was observed to associate with high mortality, presenting a U-shaped curve, which was further confirmed by a similar cohort study in Danish population ( 47 , 48 ). Although some studies showed that thrombocytopenia is a poor prognostic factor for cancer patients ( 49 , 50 ), a nested case-control study over a 10-year period gave a final answer in 2022 that an elevated platelet count was associated with cancer at several sites and could potentially serve as a marker for the presence of some cancer types ( 51 ).…”

Screening for occult cancer after unprovoked venous thromboembolism: Assessing the current literature and future directions

“…Thrombocytosis has been identified as an independent biomarker of malignancy. Tumor cells are thought to induce platelet formation through release of cytokine IL‐6 which stimulates thrombopoietin production, megakaryocyte cell division in the bone marrow, and platelet formation 24 . A nested case–control of 8 917 187 patients measuring elevated platelet count on CBC with matched controls found that an elevated platelet count was associated with a cancer diagnosis within 10 years of the blood test.…”

“…A nested case–control of 8 917 187 patients measuring elevated platelet count on CBC with matched controls found that an elevated platelet count was associated with a cancer diagnosis within 10 years of the blood test. Another study found the association of thrombocytosis and a subsequent diagnosis of cancer was greatest for colon, lung, ovarian, and gastric cancers 24 . Researchers from that study proposed platelet count could potentially be used as an independent biomarker for presence of undiagnosed malignancy.…”