{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T12:29:57Z","timestamp":1787228997524,"version":"build-2736575974"},"reference-count":6,"publisher":"BMJ","issue":"9","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["J Clin Pathol"],"accepted":{"date-parts":[[2026,6,6]]},"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:p>\n                    B cell acute lymphoblastic leukaemia (B-ALL) infrequently presents with undetectable or very low peripheral blood (PB) lymphoblasts, which may cause diagnostic difficulties. We report the clinicopathological features of paediatric patients with B-ALL who presented with low (&lt;5%; n=31) PB lymphoblasts by flow cytometry. 15 patients presented with &lt;1%\u2009PB lymphoblasts (range: 0.0%\u20130.9%), a level potentially undetectable by manual smear review and standard 100-cell count. Compared with patients presenting with \u22655%\u2009PB lymphoblasts (n=45), those with &lt;5% had more frequent musculoskeletal symptoms, less frequent lymphadenopathy and hepatosplenomegaly, higher platelet counts, lower white blood cell counts and lower lactate dehydrogenase. The presence of low PB lymphoblasts was associated with favourable cytogenetics (\n                    <jats:italic>ETV6::RUNX1<\/jats:italic>\n                    or high hyperdiploidy without\n                    <jats:italic>IKZF1<\/jats:italic>\n                    deletion) and less frequent central nervous system involvement. Aleukemic\/low PB lymphoblast presentation of B-ALL is associated with unique clinicopathological features that overlap with non-malignant disorders. A high degree of clinical suspicion and careful review of PB flow cytometry data are required for timely diagnosis.\n                  <\/jats:p>","DOI":"10.1136\/jcp-2026-210639","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T17:20:15Z","timestamp":1782321615000},"page":"629-633","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Paediatric B-lymphoblastic leukaemia with low peripheral blasts: a potential diagnostic pitfall"],"prefix":"10.1136","volume":"79","author":[{"given":"Emily M","family":"Harris","sequence":"first","affiliation":[{"name":"Dana-Farber\/Boston Children\u2019s Cancer and Blood Disorders Center, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew M","family":"Heeney","sequence":"additional","affiliation":[{"name":"Dana-Farber\/Boston Children\u2019s Cancer and Blood Disorders Center, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew E","family":"Place","sequence":"additional","affiliation":[{"name":"Dana-Farber\/Boston Children\u2019s Cancer and Blood Disorders Center, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marian H","family":"Harris","sequence":"additional","affiliation":[{"name":"Department of Pathology, Boston Children\u2019s Hospital, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark D","family":"Fleming","sequence":"additional","affiliation":[{"name":"Department of Pathology, Boston Children\u2019s Hospital, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lewis B","family":"Silverman","sequence":"additional","affiliation":[{"name":"Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Irving Medical Center, New York, New York, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2387-5462","authenticated-orcid":false,"given":"Jacob R","family":"Bledsoe","sequence":"additional","affiliation":[{"name":"Department of Pathology, Boston Children\u2019s Hospital, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,6,24]]},"reference":[{"key":"2026082005150913000_79.9.629.1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMra1400972"},{"key":"2026082005150913000_79.9.629.2","doi-asserted-by":"crossref","first-page":"338","DOI":"10.1111\/bjh.18552","article-title":"Characterisation of children and adolescents with acute lymphoblastic leukaemia who presented without peripheral blood blasts at diagnosis","volume":"200","author":"Mangum","year":"2023","journal-title":"Br J Haematol"},{"key":"2026082005150913000_79.9.629.3","first-page":"537","article-title":"The absence of peripheral blood blasts at diagnosis may predict CNS involvement or CNS relapse in pediatric acute lymphoblastic leukemia patients","volume":"50","author":"Unal","year":"2008","journal-title":"Turk J Pediatr"},{"key":"2026082005150913000_79.9.629.4","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1200\/JCO.1996.14.1.18","article-title":"Uniform approach to risk classification and treatment assignment for children with acute lymphoblastic leukemia","volume":"14","author":"Smith","year":"1996","journal-title":"J Clin Oncol"},{"key":"2026082005150913000_79.9.629.5","doi-asserted-by":"publisher","DOI":"10.1182\/bloodadvances.2017014704"},{"key":"2026082005150913000_79.9.629.6","doi-asserted-by":"publisher","DOI":"10.1136\/jclinpath-2018-205172"}],"container-title":["Journal of Clinical Pathology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/jcp-2026-210639","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T12:15:28Z","timestamp":1787228128000},"score":1,"resource":{"primary":{"URL":"https:\/\/jcp.bmj.com\/lookup\/doi\/10.1136\/jcp-2026-210639"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,24]]},"references-count":6,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,8,20]]},"published-print":{"date-parts":[[2026,9]]}},"alternative-id":["10.1136\/jcp-2026-210639"],"URL":"https:\/\/doi.org\/10.1136\/jcp-2026-210639","relation":{},"ISSN":["0021-9746","1472-4146"],"issn-type":[{"value":"0021-9746","type":"print"},{"value":"1472-4146","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,24]]}}}