Table 1

Clinical characteristics of the patients

Case
no.
Age (years)/SexRevelatory symptomPeritoneal involvement (mass/diffuse)Surgical/Needle biopsyFirst proposed histological diagnosisMutational statusFinal diagnosisTime delay until final diagnosis (months)*Other organs involvedEvolution, status (months after biopsy)
0173/MAbd painDiffuseNeedleInflammationWT*ECD7Bones, r&pr,AWD (21)
0217/MPeripheral oedemaDiffuseSurgicalECDMAP2K1ECD51r&pr, heart, kidney, testisAWD (24)
0354/MAbd painMass (3 cm)SurgicalECDWT*Sclerosing mesenteritis6NoAWD (0)
0479/MAbd painMassSurgicalSclerosing mesenteritisWTSclerosing mesenteritis5NoAWD (6)
0560/FAbd painMassSurgicalECDWT, NF1Sclerosing mesenteritis5NoAWD (30)
0675/FAnaemiaMassSurgicalInflammationWT*Histiocytosis NOS2NoPostop death
0755/MIschaemic cardiopathyDiffuseSurgicalECDBRAFECD49MediastinumDOD
0843/MFeverMassSurgicalECDBRAFECD9r&pr, bonesNo follow-up
0963/MAsymptomaticMassSurgicalFibrosisWT*ECD9Kidney, bonesAWD
1036/MAbd painMassSurgicalSclerosing mesenteritisBRAFECD53Exophthalmia, skin, kidneys, bonesAWD (90)
1171/MAbd painMass (15 cm)NeedleSclerosing mesenteritisBRAFECD15CNS, periaortic, r&prAWD (12)
1244/FBone painMass (11 cm)SurgicalECDBRAFECD4BonesAWD (8)
1336/FAbd painDiffuseSurgicalLiposarcomaWT*Histiocytosis NOS28Liver, bone marrowDOD
1473/MFever, astheniaDiffuseSurgicalInflammationBRAFECD3Bones, bone marrowAWD (10)
1568/FWeight lossDiffuseSurgicalInflammationBRAFECD2Bones, r&pr, CNSAWD (45)
1654/MAbd painDiffuseSurgicalInflammationBRAFECD23MediastinumDOD (72)
1758/MAsymptomaticMass (4 cm)NeedleSclerosing mesenteritisWT*Sclerosing mesenteritis27NoAWD (2)
1866/MAbd painDiffuseSurgicalECDMAP2K1ECD3Bones, heart, CNSDOD (17)
1972/MAbd painDiffuseSurgicalECDBRAFECD49Bones, heart, orbit, aortaDOD (33)
2051/FAsymptomaticDiffuseSurgicalInflammationWTXanthogranulomatous peritonitis17NoAWD (2)
2166/MXanthelasma, retroperitoneal fibrosisDiffuseSurgicalInflammationBRAFECD23Liver‡, spleen, bones, r&pr, pericardium, retroorbital, skinAWD
2254/MGeneral state alterationMass (13 cm)SurgicalECDBRAFECD6Liver‡, spleen, bones, r&pr, pericardiumAWD (9)
  • Patients 2 and 7 have mixed histiocytoses (ECD/RDD and ECD/Langerhans cell histiocytosis, respectively). Patient 11 had an associated chronic myelomonocytic leukaemia, patient 14 had an associated MDS and patient 7 developed a MDS during follow-up.

  • *Time between the first symptom (or, where we do not have the information, the date of the first peritoneal biopsy) and the diagnosis of histiocytosis.

  • †Molecular analysis limited to BRAFV600E, because of the low amount/quality of DNA obtained from the involved tissue.

  • ‡Hepatomegaly.

  • Abd, abdominal; AWD, alive with disease; CNS, central nervous system; DOD, deceased of disease; ECD, Erdheim-Chester disease; F, female; M, male; MDS, myelodysplastic syndrome; NOS, not otherwise specified; RDD, Rosai-Dorfman disease; r&pr, retroperitoneal and perirenal; WT, no mutation of the genes of the MAP kinase pathway detected.