{
  "schemaVersion": 2,
  "eyebrow": "Hematologic Oncology",
  "title": "Hairy Cell Leukemia",
  "summary": "Confirm classic HCL with integrated morphology, immunophenotyping, and BRAF V600E assessment; treat only clinically consequential disease, then select purine analog, BRAF-directed therapy, or relapse-directed treatment by infection status, fitness, and remission duration.",
  "seoDescription": "Point-of-care diagnosis and treatment selection for classic hairy cell leukemia, including observation, purine analogs, BRAF therapy, and relapse management.",
  "clinicalQuestion": "How should physicians confirm, stage treatment need, and select first-line or relapse therapy for classic hairy cell leukemia?",
  "specialty": "Hematology-Oncology",
  "audience": "U.S. physicians and medical trainees",
  "tags": [
    "hairy cell leukemia",
    "classic HCL",
    "HCL variant",
    "BRAF V600E",
    "cladribine",
    "pentostatin",
    "vemurafenib",
    "rituximab"
  ],
  "keyTakeaways": [
    "Classic HCL usually presents with cytopenias, splenomegaly, and circulating or marrow hairy cells; establish the diagnosis with marrow-based morphologic and immunophenotypic evaluation rather than blood counts alone. [1][8]",
    "Do not treat asymptomatic, stable disease automatically; observe until treatment indications emerge. [4]",
    "Cladribine or pentostatin remains standard first-line therapy for classic HCL, but complete pretreatment infection assessment and infection control before a purine analog. [4]",
    "For active infection, renal insufficiency, or frailty that makes purine-analog therapy unsuitable, consider vemurafenib, alone or with rituximab or obinutuzumab, to obtain comparatively rapid count recovery. [4]",
    "At relapse after at least 2 years, retreatment with cladribine or pentostatin is often effective; earlier relapse or refractory disease should prompt non–purine-analog strategies and reassessment of disease biology. [1][23]",
    "Vemurafenib plus rituximab is a chemotherapy-free option for relapsed or refractory classic HCL, producing complete response in 87%, MRD-negative status in 60%, and relapse-free survival of 85% at a median 34 months in a prospective study. [5]"
  ],
  "sections": [
    {
      "id": "confirm-diagnosis",
      "eyebrow": "Diagnosis",
      "heading": "Confirm classic HCL and separate it from biologically distinct mimics",
      "intro": "Diagnostic classification determines whether BRAF-targeted therapy and standard purine-analog expectations apply.",
      "paragraphs": [
        "Suspect HCL in a patient with otherwise unexplained cytopenias and splenomegaly, especially when peripheral blood or marrow shows lymphoid cells with irregular cytoplasmic projections. Bone marrow evaluation is central because classic HCL characteristically involves marrow and may produce peripheral cytopenias even when circulating hairy cells are sparse. [1][8]",
        "Use integrated morphology, flow cytometry, immunohistochemistry, and molecular testing to distinguish classic HCL from HCL variant and other small B-cell neoplasms. BRAF V600E testing is particularly decision-relevant: the mutation occurs in almost all classic-form HCL and provides the biologic rationale for vemurafenib; BRAF V600E immunohistochemistry can assist in the differential diagnosis. [8][23]",
        "Do not extrapolate classic-HCL treatment response to HCL variant. HCL variant has poorer and less durable responses to standard purine analogs, so a diagnostic label of HCL variant should redirect management toward disease-specific specialist planning rather than routine cladribine or pentostatin monotherapy. [12][21]"
      ],
      "bullets": [
        "Obtain a bone marrow aspirate and core biopsy when HCL is suspected from cytopenias, splenomegaly, or abnormal circulating lymphoid cells. [1][8]",
        "Request BRAF V600E assessment in suspected classic HCL, particularly before considering BRAF-directed therapy or when the pathologic differential includes HCL variant. [8][23]",
        "Review the pathology with hematopathology when morphology, immunophenotype, and BRAF status are discordant or when HCL variant remains possible. [8][12]"
      ],
      "subsections": [],
      "table": {
        "caption": "Features that alter classification and treatment expectations in hairy cell neoplasms. [1][8][12][23]",
        "columns": [
          "Finding",
          "Interpretation",
          "Next clinical action"
        ],
        "rows": [
          [
            "Cytopenias, splenomegaly, and hairy cells in blood or marrow",
            "Pattern supports HCL but is not sufficient to define the biologic subtype. [1][8]",
            "Complete marrow morphology, immunophenotyping, and molecular evaluation. [1][8]"
          ],
          [
            "BRAF V600E detected",
            "Supports classic HCL; BRAF V600E occurs in almost all classic-form cases. [23]",
            "If treatment is required and purine analogs are unsuitable or disease has relapsed, assess candidacy for vemurafenib-based therapy. [4][23]"
          ],
          [
            "HCL variant diagnosis",
            "Standard purine analogs have low response rates and less durable remissions than in classic HCL. [12]",
            "Avoid assuming standard classic-HCL outcomes; plan management with hematology expertise in HCL/HCL variant. [12][21]"
          ]
        ]
      }
    },
    {
      "id": "decide-whether-to-treat",
      "eyebrow": "Treatment Threshold",
      "heading": "Treat clinical consequences, not the diagnostic label alone",
      "intro": "The first branch is observation versus therapy; urgency depends on symptoms, cytopenia consequences, spleen-related complications, and infection.",
      "paragraphs": [
        "For stable patients without an indication for treatment, use close observation until treatment indications occur. This avoids exposing an indolent disease course to purine-analog-associated hematologic and immunologic toxicity before a treatment benefit is expected. [4][5]",
        "Escalate from observation when disease produces treatment-relevant cytopenias, symptomatic or massive splenomegaly, splenic rupture, or a platelet count low enough to preclude chemotherapy. Massive symptomatic splenomegaly or splenic rupture changes the immediate management pathway because splenic-directed intervention may be required when chemotherapy cannot be safely delivered. [1]",
        "Before initiating cladribine or pentostatin, perform pretreatment evaluation focused on infection and establish infection control. Active infection is a key reason to defer a purine analog and select a less myelosuppressive bridge or alternative regimen. [4][20]"
      ],
      "bullets": [
        "Observe closely if there is no treatment indication. [4]",
        "Treat when clinically consequential cytopenias, symptomatic massive splenomegaly, splenic rupture, or thrombocytopenia that precludes chemotherapy is present. [1]",
        "Address active infection before purine-analog therapy; do not treat infection control as an afterthought in a disease with baseline and treatment-associated immunosuppression. [4][20]"
      ],
      "subsections": [],
      "table": {
        "caption": "Initial management branch by treatment need and fitness. [1][4][20]",
        "columns": [
          "Clinical state",
          "Immediate action",
          "Treatment implication"
        ],
        "rows": [
          [
            "No current treatment indication",
            "Close observation. [4]",
            "Start therapy only when a treatment indication develops. [4]"
          ],
          [
            "Treatment indication without splenic rupture, massive symptomatic splenomegaly, or thrombocytopenia precluding chemotherapy",
            "Complete pretreatment infection evaluation and infection control. [1][4]",
            "Use a purine analog as standard first-line treatment when clinically suitable. [4]"
          ],
          [
            "Active infection, frailty, or renal insufficiency",
            "Stabilize and control infection; reassess ability to tolerate purine-analog treatment. [4]",
            "Consider vemurafenib alone or combined with rituximab or obinutuzumab if a purine analog is unsuitable. [4]"
          ],
          [
            "Massive symptomatic splenomegaly, splenic rupture, or marked thrombocytopenia precluding chemotherapy",
            "Urgently individualize management for spleen-related complication and inability to deliver chemotherapy. [1]",
            "Do not proceed as if this were routine first-line purine-analog treatment. [1]"
          ]
        ]
      }
    },
    {
      "id": "first-line-therapy",
      "eyebrow": "Initial Therapy",
      "heading": "Choose first-line therapy by infection risk and capacity to tolerate myelosuppression",
      "intro": "Classic HCL is highly responsive to purine analogs, but therapeutic timing and regimen choice must account for immunosuppression.",
      "paragraphs": [
        "For classic HCL requiring treatment and without a contraindicating infection or major fitness limitation, use cladribine or pentostatin as standard first-line therapy. Historical first-line complete remission rates with purine analogs are approximately 75% to 90%, although relapse can occur years later and repeated exposure accumulates hematologic and immunologic toxicity. [4][9]",
        "Adding rituximab concurrently to cladribine improves the MRD-free complete-response rate compared with delayed rituximab in first-line HCL. This depth-of-response advantage should be weighed against the added immune effects of anti-CD20 therapy, particularly in a patient whose infection history or current infectious status already argues for minimizing immunosuppression. [4][20]",
        "When a purine analog is unsuitable because of active infection, frailty, or renal insufficiency, vemurafenib is an alternative that can be used alone or with rituximab or obinutuzumab. Vemurafenib-based initial treatment has demonstrated rapid blood-count recovery, making it particularly useful when count restoration is needed but purine-analog myelosuppression is undesirable. [4][6]",
        "If pentostatin produces a complete response, two or three additional pentostatin doses may be considered. Document response using standardized response assessment because response, relapse, and MRD definitions remain important for comparing treatment programs; MRD testing has not been validated as a clinically significant endpoint for routine decision-making. [4][20][23]"
      ],
      "bullets": [
        "Use cladribine or pentostatin as standard first-line therapy for eligible classic HCL. [4]",
        "Consider cladribine plus concurrent rituximab when pursuit of an MRD-free complete response is an explicit treatment objective. [4]",
        "Use vemurafenib-based treatment rather than forcing purine-analog therapy in active infection, renal insufficiency, or frailty. [4]",
        "Do not use MRD status alone as a validated trigger for treatment escalation outside an appropriate protocol or individualized specialist decision. [23]"
      ],
      "subsections": [],
      "table": {
        "caption": "First-line regimen selection for classic HCL requiring treatment. [4][6][9][23]",
        "columns": [
          "Patient context",
          "Preferred therapeutic direction",
          "Key tradeoff"
        ],
        "rows": [
          [
            "Fit patient without active infection or major renal limitation",
            "Cladribine or pentostatin. [4]",
            "High response rates, but purine analogs cause hematologic and immunologic toxicity. [5][9]"
          ],
          [
            "Need to maximize MRD-free complete response",
            "Cladribine with concurrent rituximab. [4]",
            "Improves MRD-free complete response compared with delayed rituximab; adds anti-CD20-mediated immune effects. [4][20]"
          ],
          [
            "Active infection, frailty, or renal insufficiency",
            "Vemurafenib alone or with rituximab or obinutuzumab. [4]",
            "Can provide rapid count recovery while avoiding initial purine-analog treatment. [4][6]"
          ],
          [
            "Complete response after pentostatin",
            "Consider two or three additional pentostatin doses. [4]",
            "Use response assessment to guide completion of therapy. [4]"
          ]
        ]
      }
    },
    {
      "id": "relapsed-refractory-disease",
      "eyebrow": "Relapse Management",
      "heading": "Use remission duration and prior purine-analog sensitivity to direct salvage therapy",
      "intro": "Rebiopsy or reassess disease biology when relapse is early, refractory, or clinically atypical.",
      "paragraphs": [
        "At relapse, first distinguish late relapse from early relapse or refractory disease. Patients relapsing after a first purine-analog course often respond to retreatment with the same or another purine analog, particularly when relapse occurs after 2 years; this is the principal setting in which another purine-analog course remains reasonable. [1][23]",
        "Avoid serially repeating purine analogs without considering cumulative toxicity and diminishing benefit. Relapsed HCL can become progressively less sensitive to purine analogs, and repeated courses produce cumulative hematologic and immunologic toxicity. Cross-resistance between cladribine and pentostatin can occur. [5][9]",
        "For BRAF V600E-positive relapsed or refractory classic HCL, vemurafenib with rituximab offers a chemotherapy-free strategy. In a prospective study of heavily pretreated patients, this combination achieved complete response in 87%, MRD-negative status in 60%, and relapse-free survival of 85% at a median follow-up of 34 months. [5]",
        "Rituximab alone can induce durable complete remissions with minimal toxic effects in multiply relapsing or refractory HCL after prior purine analog therapy, while combinations or sequential rituximab with cladribine or pentostatin are effective for complete-remission induction. Choose between these approaches according to prior purine-analog sensitivity, cumulative immunosuppression, and the need for a chemotherapy-free regimen. [23]",
        "For multiply relapsed disease, enroll in a clinical trial whenever feasible. This is particularly important after loss of durable benefit from purine analogs or BRAF-directed therapy and in HCL variant, where standard classic-HCL treatment assumptions are unreliable. [20][21]"
      ],
      "bullets": [
        "Late relapse of at least 2 years after initial purine-analog therapy: consider retreatment with cladribine or pentostatin. [1][23]",
        "Early relapse or purine-analog-refractory disease: prioritize a non–purine-analog strategy and reassess BRAF V600E status and diagnostic classification. [1][5][23]",
        "BRAF V600E-positive relapsed or refractory classic HCL: consider vemurafenib plus rituximab. [5][23]",
        "Multiply relapsed or refractory disease: consider rituximab-based therapy and clinical-trial referral. [20][23]"
      ],
      "subsections": [],
      "table": {
        "caption": "Salvage-treatment selection by relapse pattern. [1][5][9][23]",
        "columns": [
          "Relapse pattern",
          "Reasonable next option",
          "Decision constraint"
        ],
        "rows": [
          [
            "Relapse at least 2 years after first cladribine or pentostatin",
            "Retreat with the same or another purine analog. [23]",
            "Expected benefit is greatest after a longer first remission. [1][23]"
          ],
          [
            "Early relapse or purine-analog-refractory classic HCL",
            "Vemurafenib with rituximab when BRAF V600E-positive. [5][23]",
            "Avoid relying on further purine-analog exposure when prior sensitivity is limited and cumulative toxicity is a concern. [5][9]"
          ],
          [
            "Multiply relapsed or refractory disease",
            "Rituximab alone, or rituximab combined or sequenced with cladribine or pentostatin; pursue clinical trial when feasible. [20][23]",
            "Balance disease control against prior purine-analog exposure and immunosuppression. [5][23]"
          ],
          [
            "HCL variant",
            "Subtype-directed specialist and trial-oriented planning. [12][21]",
            "Responses to standard purine analogs are less favorable and less durable. [12]"
          ]
        ]
      }
    },
    {
      "id": "monitoring-and-complications",
      "eyebrow": "Follow-up",
      "heading": "Monitor for count recovery, infection, relapse, and clinically meaningful response",
      "intro": "Follow-up should identify treatment toxicity and recurrence while avoiding treatment changes based only on unvalidated MRD endpoints.",
      "paragraphs": [
        "Track blood counts and clinical spleen-related symptoms during treatment and follow-up, because cytopenia recovery and resolution of disease-related manifestations are the immediate measurable objectives of therapy. Vemurafenib-based therapy has been associated with rapid count recovery in initial treatment, whereas purine analogs require particular attention to hematologic and immunologic toxicity. [4][5]",
        "Maintain a low threshold to evaluate fever or focal infectious symptoms before, during, and after treatment because HCL is associated with marked susceptibility to infection and effective therapies can deepen immunosuppression. Before any subsequent purine-analog course, repeat pretreatment evaluation and infection-control planning rather than assuming a prior uncomplicated course predicts safety. [4][20]",
        "Use clinical status, blood counts, and standardized response assessment to determine relapse requiring intervention. MRD testing may characterize depth of response, but its clinical significance as a routine endpoint has not been validated; do not treat MRD positivity alone as established evidence of a need for salvage therapy. [20][23]"
      ],
      "bullets": [
        "Monitor serial blood counts for hematologic response and treatment-related cytopenias. [4][5]",
        "Reassess infectious risk before each purine-analog exposure. [4][20]",
        "Use MRD results cautiously; they are not a validated stand-alone endpoint for routine treatment decisions. [23]"
      ],
      "subsections": [],
      "table": {
        "caption": "Follow-up findings that should change management. [4][20][23]",
        "columns": [
          "Follow-up finding",
          "Interpretation",
          "Action"
        ],
        "rows": [
          [
            "Blood-count recovery after therapy",
            "Supports hematologic response. [4][5]",
            "Continue response assessment and monitor for recurrent cytopenias. [4]"
          ],
          [
            "Fever or suspected infection before planned purine analog",
            "Purine-analog treatment may worsen infection-related risk. [4][20]",
            "Control infection and reassess treatment timing and regimen selection. [4]"
          ],
          [
            "MRD positivity without clinical relapse",
            "MRD is not validated as a clinically significant routine endpoint. [23]",
            "Do not use MRD alone as an established indication for salvage therapy. [23]"
          ],
          [
            "Recurrent cytopenias or symptomatic splenomegaly after remission",
            "May indicate clinically meaningful relapse. [1][23]",
            "Reassess disease status, remission duration, prior therapy, and BRAF-directed options. [1][5][23]"
          ]
        ]
      }
    }
  ],
  "faq": [],
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      "title": "Chronic lymphocytic leukemia - Guidelines | BMJ Best Practice US",
      "detail": "bestpractice.bmj.com",
      "url": "https://bestpractice.bmj.com/topics/en-gb/275/guidelines",
      "authors": "bestpractice.bmj.com",
      "host": "bestpractice.bmj.com",
      "snippet": "Title: Chronic lymphocytic leukemia - Guidelines | BMJ Best Practice US\n# Chronic lymphocytic leukemia. ## International guidelines. ### Chronic lymphocytic leukemia/small lymphocytic lymphomaNational Comprehensive Cancer Network. NCCN clinical practice guidelines in oncology: chronic lymphocytic le",
      "score": 0.46147847
    },
    {
      "number": 4,
      "title": "Hairy cell leukaemia - Treatment algorithm | BMJ Best Practice",
      "detail": "bestpractice.bmj.com",
      "url": "https://bestpractice.bmj.com/topics/en-gb/890/treatment-algorithm",
      "authors": "bestpractice.bmj.com",
      "host": "bestpractice.bmj.com",
      "snippet": "Title: Hairy cell leukaemia - Treatment algorithm | BMJ Best Practice\ntool=bestpractice.com ​ For these patients, close observation is recommended until indications for treatment occur.Parry-Jones N, Joshi A, Forconi F, et al. A purine analogue (cladribine or pentostatin) is standard first-line trea",
      "score": 0.8849276
    },
    {
      "number": 5,
      "title": "Vemurafenib plus Rituximab in Refractory or Relapsed Hairy-Cell Leukemia | New England Journal of Medicine",
      "detail": "www.nejm.org",
      "url": "https://www.nejm.org/doi/full/10.1056/NEJMoa2031298",
      "authors": "www.nejm.org",
      "host": "www.nejm.org",
      "snippet": "Hairy-cell leukemia (HCL) is an indolent, mature B-cell neoplasm1-3 that is highly responsive to the purine analogues cladribine and pentostatin.4-7 However, up to 58% of patients with HCL have a relapse,8 with the disease becoming progressively less sensitive to purine analogues, which also cause c",
      "score": 0.81025416
    },
    {
      "number": 6,
      "title": "Vemurafenib and Obinutuzumab as Frontline Therapy for ...",
      "detail": "evidence.nejm.org",
      "url": "https://evidence.nejm.org/doi/full/10.1056/EVIDoa2300074",
      "authors": "evidence.nejm.org",
      "host": "evidence.nejm.org",
      "snippet": "by JH Park · 2023 · Cited by 31 — Very long-term eradication of minimal residual disease in patients with hairy cell leukemia after a single course of cladribine.",
      "score": 0.70336664
    },
    {
      "number": 7,
      "title": "Targeting Mutant BRAF in Relapsed or Refractory Hairy- ...",
      "detail": "www.nejm.org",
      "url": "https://www.nejm.org/doi/full/10.1056/NEJMoa1506583",
      "authors": "www.nejm.org",
      "host": "www.nejm.org",
      "snippet": "by E Tiacci · 2015 · Cited by 405 — In conclusion, we found that vemurafenib is an active targeted drug for patients with relapsed or refractory hairy-cell leukemia. Notes. Drs. Tiacci and Park",
      "score": 0.6030211
    },
    {
      "number": 8,
      "title": "Immunohistochemistry for BRAF V600E in the Differential ...",
      "detail": "academic.oup.com",
      "url": "https://academic.oup.com/ajcp/article-pdf/144/1/87/24999941/ajcpath144-0087.pdf",
      "authors": "academic.oup.com",
      "host": "academic.oup.com",
      "snippet": "by S Turakhia · 2015 · Cited by 24 — Hairy cell leukemia (HCL) is a small B-cell neoplasm that presents with splenomegaly, bone marrow involve- ment, and peripheral blood cytopenias.1-3 ...Read more",
      "score": 0.6649108
    },
    {
      "number": 9,
      "title": "Phase 2 trial of rituximab with either pentostatin or bendamustine for multiply relapsed or refractory hairy cell leukemia - ScienceDirect",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/pii/S0006497125024474",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "Title: Phase 2 trial of rituximab with either pentostatin or bendamustine for multiply relapsed or refractory hairy cell leukemia - ScienceDirect\nThe primary objective in multiply relapsed hairy cell leukemia and variant (HCL/HCLv) was to determine whether pentostatin-rituximab (DCFR) and bendamusti",
      "score": 0.8194462
    },
    {
      "number": 10,
      "title": "How I treat refractory/relapsed hairy cell leukemia with ...",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/pii/S0006497122002014",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "by B Falini · 2022 · Cited by 39 — Hairy cell leukemia (HCL) responds very well to frontline chemotherapy with purine analogs (cladribine and pentostatine).",
      "score": 0.79561085
    },
    {
      "number": 11,
      "title": "Consensus guidelines for the diagnosis and management ...",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/pii/S0006497120337289",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "by MR Grever · 2017 · Cited by 347 — Vemurafenib has been reported to be effective in patients with hairy cell leukemia in relapse after primary purine analog therapy.",
      "score": 0.7467494
    },
    {
      "number": 12,
      "title": "Hairy cell leukemia: Update on molecular profiling and ...",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/pii/S0268960X14000514",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "by MR Grever · 2014 · Cited by 55 — Patients with hairy cell leukemia variant do not respond well to standard purine analog treatment with low response rates and less durable remissions.",
      "score": 0.67501575
    },
    {
      "number": 13,
      "title": "Hairy cell leukemia 2018: Update on diagnosis, riskâ",
      "detail": "onlinelibrary.wiley.com",
      "url": "https://onlinelibrary.wiley.com/doi/pdf/10.1002%2Fajh.24936",
      "authors": "onlinelibrary.wiley.com",
      "host": "onlinelibrary.wiley.com",
      "snippet": "by X Troussard · 2017 · Cited by 98 — Targeting mutant BRAF in relapsed or refractory hairy-cell leukemia. ... rituximab for the treatment of patients with variant hairy cell ...Read more",
      "score": 0.6773251
    },
    {
      "number": 14,
      "title": "Hairy cell leukemia 2024: Update on diagnosis, risk‐ ...",
      "detail": "onlinelibrary.wiley.com",
      "url": "https://onlinelibrary.wiley.com/doi/10.1002/ajh.27240",
      "authors": "onlinelibrary.wiley.com",
      "host": "onlinelibrary.wiley.com",
      "snippet": "VH4-34 positive HCL cases are associated with a poor prognosis, Management of relapsed/refractory disease is based on the use of BRAF",
      "score": 0.56489134
    },
    {
      "number": 15,
      "title": "Hairy cell leukemia 2022: Update on diagnosis, riskâ",
      "detail": "onlinelibrary.wiley.com",
      "url": "https://onlinelibrary.wiley.com/doi/pdf/10.1002/ajh.26390",
      "authors": "onlinelibrary.wiley.com",
      "host": "onlinelibrary.wiley.com",
      "snippet": "by X Troussard · 2022 · Cited by 70 — Management of relapsed/ refractory disease is based on the use of BRAF inhibitors ・ adding rituximab (R) to CDA has been recently proven to",
      "score": 0.5530473
    },
    {
      "number": 16,
      "title": "Patients with relapsed/refractory hairy‐cell leukemia",
      "detail": "onlinelibrary.wiley.com",
      "url": "https://onlinelibrary.wiley.com/doi/full/10.1002/cnr2.1495",
      "authors": "onlinelibrary.wiley.com",
      "host": "onlinelibrary.wiley.com",
      "snippet": "by J Paillassa · 2022 · Cited by 16 — Hairy cell leukemia (HCL) is a rare chronic B-cell neoplasm with good long-term prognosis. First and second-line therapies include purine",
      "score": 0.53895956
    },
    {
      "number": 17,
      "title": "ESMO Clinical Practice Guideline: Hairy Cell Leukaemia",
      "detail": "www.esmo.org",
      "url": "https://www.esmo.org/guidelines/esmo-clinical-practice-guideline-hairy-cell-leukaemia",
      "authors": "www.esmo.org",
      "host": "www.esmo.org",
      "snippet": "Title: ESMO Clinical Practice Guideline: Hairy Cell Leukaemia\n# ESMO Clinical Practice Guideline: Hairy Cell Leukaemia | ESMO. *   ESMO Oncologist of the Year Award. *   ESMO Award for Translational Research. *   ESMO Women for Oncology Award. *   ESMO Award for Immuno-Oncology. *   ESMO-Magnitude o",
      "score": 0.8306082
    },
    {
      "number": 18,
      "title": "Chapter 23: Non-Hodgkin lymphomas - ASH Publications",
      "detail": "ashpublications.org",
      "url": "https://ashpublications.org/books/book/6/chapter/77771/Non-Hodgkin-lymphomas",
      "authors": "ashpublications.org",
      "host": "ashpublications.org",
      "snippet": "Hairy cell leukemia HCL is an indolent B-cell lymphoproliferative disorder accounting for only 2% of all leukemias; Revised guidelines for the diagnosis and",
      "score": 0.6803909
    },
    {
      "number": 19,
      "title": "Updated consensus guidelines for the diagnosis ... - ASH Publications",
      "detail": "ashpublications.org",
      "url": "https://ashpublications.org/blood/article-split/doi/10.1182/blood.2025032757/567757/Updated-consensus-guidelines-for-the-diagnosis-and",
      "authors": "ashpublications.org",
      "host": "ashpublications.org",
      "snippet": "Updated consensus guidelines for the diagnosis and management of patients with hairy cell leukemia (HCL) and HCL-variant Available · Article PDF first page",
      "score": 0.67527276
    },
    {
      "number": 20,
      "title": "Consensus guidelines for the diagnosis and management of patients with classic hairy cell leukemia - PubMed",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=27903528&dopt=Abstract",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "Title: Consensus guidelines for the diagnosis and management of patients with classic hairy cell leukemia - PubMed\nAn official website of the United States government. **The .gov means it’s official.**. Federal government websites often end in .gov or .mil. sharing sensitive information, make sure y",
      "score": 0.63125396
    },
    {
      "number": 21,
      "title": "Updated consensus guidelines for the diagnosis and ...",
      "detail": "ashpublications.org",
      "url": "https://ashpublications.org/blood/article/148/1/31/567757/Updated-consensus-guidelines-for-the-diagnosis-and",
      "authors": "ashpublications.org",
      "host": "ashpublications.org",
      "snippet": "Jul 2, 2026 — Hairy cell leukemia (HCL) and HCL variant (HCLv) are uncommon chronic B-cell neoplasms that share several clinical and pathological features",
      "score": 0.5849357
    },
    {
      "number": 22,
      "title": "Consensus guidelines for the diagnosis and management of ...",
      "detail": "ashpublications.org",
      "url": "https://ashpublications.org/blood/article/129/5/553/36153/Consensus-guidelines-for-the-diagnosis-and",
      "authors": "ashpublications.org",
      "host": "ashpublications.org",
      "snippet": "by MR Grever · 2017 · Cited by 347 — Hairy cell leukemia is an uncommon hematologic malignancy characterized by pancytopenia and marked susceptibility to infection.Read more",
      "score": 0.5479727
    },
    {
      "number": 23,
      "title": "Hairy Cell Leukemia Treatment (PDQ®) - PDQ Cancer Information Summaries - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK65741.4",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "### References\n\n## Relapsed or Refractory Hairy Cell Leukemia\n\n### Treatment Options for Relapsed or Refractory Hairy Cell Leukemia\n\nTreatment options for relapsed or refractory hairy cell leukemia include the following:\n\n#### Re-treatment with cladribine or pentostatin\n\nPatients with hairy cell leu",
      "score": 0.8588255
    },
    {
      "number": 24,
      "title": "The Chemotherapy-Free Combination of Vemurafenib and ...",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/pii/S0006497119809266",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "by E Tiacci · 2017 · Cited by 14 — The Chemotherapy-Free Combination of Vemurafenib and Rituximab Produces Deep and Durable Responses in Relapsed or Refractory Hairy Cell Leukemia (HCL) Patients.",
      "score": 0.62770075
    }
  ],
  "publishedAt": "2026-08-21T02:14:30.803460+00:00",
  "updatedAt": "2026-08-21T02:14:30.803460+00:00",
  "readingMinutes": 6,
  "slug": "hairy-cell-leukemia"
}