Risk organs and special sites

Possibly involved organs

After the diagnosis of LCH has been made, involvement of other organs should be evaluated and defined according to the clinical, biological or radiological criteria.

Risk organs (bone marrow, liver, spleen, CNS)

Involvement in the hematopoietic system (extremely rare in adults), spleen, liver or CNS indicates a less favorable prognosis, with possible mortality if the patient does not respond to therapy. Although this has never been proven for adults, retrospective analyses of national registries and the experts’ experience support the existence of the above mentioned “risk organs”.

Fever, night-sweats and weight loss combined with poor performance score might predict the rarely observed aggressive course of LCH in adults comparable to that of high grade non-Hodgkin lymphoma [Szturz et al 2010; Teng et al 2005]

“Special Sites” and “CNS-Risk” bone involvement

Vertebral lesions with intraspinal or cranofacial bone lesions with soft tissue extensions (orbit, mastoid, sphenoid or temporal bones) may cause immediate risk to the patient because of the critical anatomical site and the hazards of attempting local therapy. Isolated disease in these “Special Sites” justifies systemic therapy for children because of spinal cord compression and the association of cranio-facial bone lesions with an increased risk of developing diabetes insipidus [Grois et al 2006]. It is unclear if this connection might be extrapolated to adults, but most experts treating LCH patient follow the same guidelines for their adult patients as with the pediatric cases. (Grade D2 *)

* Grades of recommendation see here.