{"entity":{"id":"primary-cutaneous-follicle-centre-lymphoma","kind":"cancer","name":"Primary cutaneous follicle centre lymphoma","aka":["Primary cutaneous follicular lymphoma","Primary cutaneous follicle center lymphoma","PCFCL","Crosti lymphoma","Reticulohistiocytoma of the dorsum"],"tldr":"Primary cutaneous follicle centre lymphoma is a slow-growing lymphoma of germinal-centre B cells that stays in the skin, usually as lumps on the head or trunk. Its outlook is excellent, with about 95 in 100 people alive at five years, and radiotherapy or excision is usually all that is needed; the important thing is not to mistake it for the aggressive leg-type large B-cell lymphoma.","summary":"WHO-HAEM5 lists primary cutaneous follicle centre lymphoma among the cutaneous B-cell lymphomas as a distinct entity from follicular lymphoma, defined by follicle centre cells in the skin with no extracutaneous disease at staging (Alaggio 2022). It has a five-year overall survival of about 95 percent against about 50 percent for primary cutaneous large B-cell lymphoma, leg type, and the two are separated in practice by IgM staining, present in all 40 leg-type cases and only 5 of 53 follicle centre cases in the defining study (Am J Surg Pathol 2010). Its molecular landscape differs from classic follicular lymphoma: 27 percent lack CD10 but all express MEF2B and HGAL, TNFRSF14 is the most commonly mutated gene (40 percent, with a further 10 percent carrying 1p36 deletions), followed by CREBBP, TNFAIP3, KMT2D, SOCS1, EP300, STAT6 and FOXO1, and BCL2 rearrangements are usually absent (Human Pathology 2020).\n\nHow it differs from its parent: it is skin-confined, rarely carries the t(14;18) that defines nodal follicular lymphoma, is not graded or staged as follicular lymphoma is, and is cured locally in most cases; the parent's chemoimmunotherapy is reserved for the rare disseminated case.\n\nHow common: no registry share in the sources read.\n\nTreatment: local radiotherapy or excision for solitary or localised lesions; rituximab for multifocal skin disease; the parent's systemic pathways only for extracutaneous spread; skin relapses are common and treated locally again (Am J Surg Pathol 2010 for the survival figures).","asOf":"2026-09-24","wikipedia":"https://en.wikipedia.org/wiki/Primary_cutaneous_follicle_center_lymphoma","links":[{"label":"NCI PDQ: adult non-Hodgkin lymphoma treatment","url":"https://www.cancer.gov/types/lymphoma/patient/adult-nhl-treatment-pdq"},{"label":"Alaggio 2022, Leukemia: the 5th edition WHO classification of haematolymphoid tumours, lymphoid neoplasms","url":"https://doi.org/10.1038/s41375-022-01620-2"},{"label":"Am J Surg Pathol 2010: IgM distinguishes primary cutaneous large B-cell lymphoma, leg type from follicle centre lymphoma","url":"https://doi.org/10.1097/pas.0b013e3181e5060a"},{"label":"Human Pathology 2020: molecular landscape of primary cutaneous follicle centre lymphoma","url":"https://doi.org/10.1016/j.humpath.2020.09.014"}],"tags":["subtype-page","wave4","haematologic","rare"],"related":["follicular-lymphoma","primary-cutaneous-marginal-zone-lymphoma","dlbcl","cutaneous-t-cell-lymphoma"],"cancers":[],"sections":[],"technologies":[],"targets":[],"drugs":["rituximab"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"group":"haematologic","burden":"Rare; the largest series in the sources read hold 53 patients (Am J Surg Pathol 2010) and 22 (Human Pathology 2020). Five-year overall survival is about 95 percent (Am J Surg Pathol 2010). No registry share is in the sources read.","subtypes":["Primary cutaneous follicle centre lymphoma, follicular growth pattern","Primary cutaneous follicle centre lymphoma, diffuse growth pattern (large centrocytes; still indolent)","Primary cutaneous follicle centre lymphoma of the leg (must be separated from leg-type large B-cell lymphoma)"],"biomarkers":["BCL6 positive; CD10 variable; MEF2B and HGAL positive","IgM negative (positive in leg-type large B-cell lymphoma)","TNFRSF14 mutation or 1p36 deletion","Usually no BCL2 rearrangement"],"standardOfCare":[{"setting":"Solitary or localised","approach":"Local radiotherapy or excision.","refs":["follicular-lymphoma"]},{"setting":"Multifocal or extracutaneous","approach":"Rituximab for multifocal skin disease; the parent's systemic pathways for the rare extracutaneous spread.","refs":["rituximab","follicular-lymphoma"]}],"stateOfArt":[],"history":[],"pipeline":[],"openProblems":[],"parent":"follicular-lymphoma"},"route":"/cancers/primary-cutaneous-follicle-centre-lymphoma/","neighbours":{"cancer":[{"id":"cutaneous-t-cell-lymphoma","kind":"cancer","name":"Cutaneous T-cell lymphoma (mycosis fungoides and Sezary syndrome)","route":"/cancers/cutaneous-t-cell-lymphoma/"},{"id":"dlbcl","kind":"cancer","name":"Diffuse large B-cell lymphoma","route":"/cancers/dlbcl/"},{"id":"follicular-lymphoma","kind":"cancer","name":"Follicular lymphoma","route":"/cancers/follicular-lymphoma/"},{"id":"primary-cutaneous-marginal-zone-lymphoma","kind":"cancer","name":"Primary cutaneous marginal zone lymphoma","route":"/cancers/primary-cutaneous-marginal-zone-lymphoma/"}],"drug":[{"id":"rituximab","kind":"drug","name":"Rituximab","route":"/drugs/rituximab/"}]}}