Histiocytic and dendritic cell neoplasms

True histiocytic and accessory dendritic cell tumours are very rare, constituting less than 1% of tumours presenting in lymph nodes. Many tumours previously thought to be of histiocytic or reticulum cells origin have been re-assigned1:

Original terminology

Current terminology

Histiocytic lymphoma, nodular and diffuse

DLBCL, follicular lymphoma, grade 3, peripheral T-cell lymphoma

Histiocytic medullary reticulosis / malignant histiocytosis

Haemophagocytic syndrome

Malignant histiocytosis

ALCL

Regressing atypical histiocytosis

Primary cutaneous ALCL

Malignant histiocytosis of the intestine

Enteropathy type T-cell lymphoma

Histiocytic cytophagic panniculitis

Subcutaneous panniculitis-like T-cell lymphoma with haemophagocytic syndrome

 

Immunohistochemistry

The following five antibodies appear to be able to reliably distinguish between the histiocytic and accessory dendritic cell neoplasms in most cases, with additional morphological and ultrastructural features resolving the cases which depart from the usual immunophenotype2.

 

CD68

lysozyme

CD1a

S-100

CD21 or CD35

histiocytic sarcoma

positive

positive

negative

variable

negative

Langerhans cell tumours

positive

variable

positive

positive

negative

Interdigitating dendritic cell tumour

variable

variable

negative

positive

negative

follicular dendritic cell tumour

variable

negative

negative

negative

positive

           

For further details, see specific tumours. Immunoglobulin T cell antigen-receptor genes should be of germline configuration.

There is a case report of a tumour showing hybrid features of follicular dendritic cell tumour and Interdigitating dendritic cell tumour3.

Prognosis

Usually aggressive neoplasms with a poor prognoses.

References

1World Health Organization Classification of Tumours, Tumours of the haematopoietic and lymphoid tissues, IARC Press 2001.

2Pileri, S.A., Grogan, T.M., Harris, N.L., Banks, P., Campo, E., Chan, J.K., Favera, R.D., Delsol, G., De Wolf-Peeters, C., Falini, B., Gascoyne, R.D., Gaulard, P., Gatter, K.C., Isaacson, P.G., Jaffe, E.S., Kluin, P., Knowles, D.M., Mason, D.Y., Mori, S., Muller-Hermelink, H.K., Piris, M.A., Ralfkiaer, E., Stein, H., Su, I.J., Warnke, R.A. and Weiss, L.M. Tumours of histiocytes and accessory dendritic cells: an immunohistochemical approach to classification from the International Lymphoma Study Group based on 61 cases. Histopathology 2002;41:1-29.

3Dillon, K.M., Hill, C.M., Cameron, C.H., Attanoos, R.L. and McCluggage, W.G. Mediastinal mixed dendritic cell sarcoma with hybrid features. J Clin Pathol 2002;55:791-4.

This page last revised 13.5.2003.

©SMUHT/PW Bishop