Table 2.

International Pediatric Non-Hodgkin Lymphoma Staging System*

International Pediatric Non-Hodgkin Lymphoma Staging System
Stage I
Single tumor with exclusion of mediastinum and abdomen (N; EN; B or S: EN-B, EN-S)
Stage II
Single EN tumor with regional node involvement
≥ Two N areas on same side of diaphragm
Primary GI tract tumor (usually in ileocecal area), ± involvement of associated mesenteric nodes, that is completely resectable (if malignant ascites or extension of tumor to adjacent organs, it should be regarded as stage III)
Stage III
≥ Two EN tumors (including EN-B or EN-S) above and/or below diaphragm
≥ Two N areas above and below diaphragm
Any intrathoracic tumor (mediastinal, hilar, pulmonary, pleural, or thymic)
Intra-abdominal and retroperitoneal disease, including liver, spleen, kidney, and/or ovary localizations, regardless of degree of resection (except primary GI tract tumor [usually in ileocecal region] ± involvement of associated mesenteric nodes that is completely resectable)
Any paraspinal or epidural tumor, regardless of whether other sites are involved
Single B lesion with concomitant involvement of EN and/or nonregional N sites
Stage IV
Any of the above findings with initial involvement of CNS (stage IV CNS), BM (stage IV BM), or both (stage IV combined) based on conventional methods

NOTE. For each stage, type of examination and degree of BM and CNS involvement should be specified. Based on classification proposed by Murphy.¹⁵

Abbreviations: B, bone; BM, bone marrow; EN, extranodal; N, nodal; S, skin.