Natural history of clonal haematopoiesis seen in real-world haematology settings

Recursive partitioning of healthy consortia led to the development of the Clonal Hematopoiesis Risk Score (CHRS) for clonal haematopoiesis (CH); however, in the practical setting, most cases of CH are diagnosed after patients present with cytopenias or related symptoms. To address this real-world population, we characterize the clinical trajectories of 94 patients with CH and distinguish CH harbouring canonical DNMT3A/TET2/ASXL1 mutations alone ('sole DTA') versus all other groups ('non-sole DTA'). TET2, rather than DNMT3A, was the most prevalent mutation in the real-world setting. Sole DTA patients did not progress to myeloid neoplasm (MN) in the absence of acquisition of other mutations. Contrastingly, 14 (20.1%) of 67 non-sole DTA patients progressed to MN. CHRS assessment showed a higher frequency of high-risk CH in non-sole DTA (vs. sole DTA) patients and in progressors (vs. non-progressors). RUNX1 mutation conferred the strongest risk for progression to MN (odds ratio [OR] 10.27, 95% CI 2.00-52.69, p = 0.0053). The mean variant allele frequency across all genes was higher in progressors than in non-progressors (36.9% ± 4.62% vs. 24.1% ± 1.67%, p = 0.0064). This analysis in the post-CHRS era underscores the natural history of CH, providing insight into patterns of progression to MN.

Prognostic heterogeneity and clonal dynamics within distinct subgroups of myelodysplastic syndrome and acute myeloid leukemia with TP53 disruptions

TP53 aberrations constitute the highest risk subset of myelodysplastic neoplasms (MDS) and acute myeloid leukemia (AML). The International Consensus Classification questions the blast threshold between MDS and AML. In this study, we assess the distinction between MDS and AML for 76 patients with TP53 aberrations. We observed no significant differences between MDS and AML regarding TP53 genomics. Median overall survival (OS) was 223 days for the entire group, but prognostic discrimination within subgroups showed the most inferior OS (46 days) for AML with multihit allelic state plus TP53 variant allele frequency (VAF) > 50%. In multivariate analysis, unadjusted Cox models revealed the following variables as independent risk factors for mortality: AML (vs. MDS) (hazard ratio [HR]: 2.50, confidence interval [CI]: 1.4-4.4, p = 0.001), complex karyotype (HR: 3.00, CI: 1.4-6.1, p = 0.003), multihit status (HR: 2.30, CI 1.3-4.2, p = 0.005), and absence of hematopoietic cell transplant (HCT) (HR: 3.90, CI: 1.8-8.9, p = 0.0009). Clonal dynamic modeling showed a significant reduction in TP53 VAF with front-line hypomethylating agents. These findings clarify the impact of specific covariates on outcomes of TP53-aberrant myeloid neoplasms, irrespective of the diagnosis of MDS versus AML, and may influence HCT decisions.

Recurrent Giant Cell Tumor of Bone with New Pulmonary Metastases 9 Years After En Bloc Distal Radius Resection: A Case Report

CASE

A 31-year-old man with a history of giant cell tumor of bone (GCTB) in the distal radius presents to clinic 9 years after en bloc distal radius resection. He was found to have a new soft tissue mass consistent with GCTB and new pulmonary metastases. Ultimately, he underwent excision of his soft tissue recurrence and partial lobectomy for his lung metastases.

CONCLUSION

This case highlights the importance of having a high level of suspicion for local recurrence or metastasis, even years after wide resection and negative margins.

Langerin staining identifies most littoral cell angiomas but not most other splenic angiomatous lesions

Although littoral cell angiomas (LCAs) are phenotypically well characterized, the antibodies used to support the diagnosis identify many other cells in the normal spleen, and some may be found in other angiomatous lesions. Based on a langerin/CD207+ LCA index case, langerin and other selected immunohistochemical staining was performed on 10 LCAs, 20 other splenic angiomatous lesions, and 7 reactive lymph nodes to further investigate the role of langerin as a diagnostic tool. Ninety percent (9/10) of LCAs were langerin positive, whereas only 1 (5%) of 20 other splenic vascular lesions was partially positive (P < .00001). All LCAs were CD1a-, CD68+, CD34-, and CD8-; 20% were S100+, 70% CD21+, and 90% cyclin D1+. Ultrastructural studies of one LCA did not show Birbeck-type granules in definite lining cells. Sinus lining cells in 7 of 7 reactive lymph nodes showed partial langerin positivity, and 4 of 4 showed partial cyclin D1 positivity. In conclusion, langerin staining is an easily interpreted and highly sensitive and specific (sensitivity [0.90], specificity [0.95]) ancillary study to help distinguish LCA from other vascular tumors of the spleen. Whether this represents cross-reactivity or true CD207 expression is uncertain, as other immunohistochemical and ultrastructural studies do not support a Langerhans cell origin. The cyclin D1 staining seen in most LCA would be consistent with their expression of other selected vascular and histiocytic markers. The similar staining pattern in some lymph node sinus lining cells suggests a possible similar cell of origin, although LCA of lymph nodes is not described.

Performance of rapid SOFIA Influenza A+B test compared to Luminex x-TAG respiratory viral panel assay in the diagnosis of influenza A, B, and subtype H3

Influenza is an acute respiratory illness caused by influenza A or B viruses that occur in outbreaks, mainly during the winter season. Rapid laboratory diagnosis of influenza can help guide the clinical management of suspected patients effectively. Clinical sensitivities and specificities of the rapid influenza diagnostic tests have varied considerably in the literature. Most of these studies are evaluated using previously frozen or stored specimens that had previously tested positive. This study compares the performance of the rapid SOFIA Influenza A+B test to nucleic acid multiplex test x-TAG respiratory viral panel (RVP) assay in freshly collected nasal aspirates and measured simultaneously by both assays. Retrospective data from 1649 nasal aspirates (September 2014 to May 2015) collected from adults as well as from children tested simultaneously by both rapid SOFIA Influenza A+B FIA immunofluorescence (Quidel, San Diego, CA) and qualitative nucleic acid multiplex RVP assay X-TAG Luminex technology (Luminex, Austin, Texas, USA) were analyzed. Concordance, and analytical sensitivity and specificity were evaluated for influenza A, subtypes H1 and H3, and influenza B. Prevalence for influenza A by RVP was 15%, for subtype H3 it was 11.2%, and for influenza B, 2.9%. None of the aspirates were positive for influenza A subtype H1. SOFIA Influenza rapid test demonstrated good specificity and low sensitivity compared with a nucleic acid test for influenza A, subtype H3, and for influenza B. SOFIA Influenza A + B test performed well in providing a rapid diagnosis, however, confirmatory molecular testing is recommended for negative test results. Re-evaluation of test performance should be periodically carried out during outbreaks with the emergence and circulation of new influenza strains.