<s>[INST] Sir,What LCA positive means is ?What is the treatment of Non Hodgkins Lymphoma ?  Which practice is followed as most appropriate in the case of person below 32 yrs of age suffering/suffered with NHL bone (LCA) Positive and no sub type.........Whether Knee Replacement with prosthesis technique is more appropriate or bone grafting arthodensis is more appropriate in case of NHL bone Tibia ?Wh [/INST] Hi, Thanks for writing in.NHL means non Hodgkin's lymphoma. LCA is leukocyte common antigen and is a marker for disease type in NHL. World Health Organization broadly classifies lymphomas into Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). Non-Hodgkin lymphoma is further subclassified based on the stage of maturation (immature vs. mature) and cell of origin [B cell, T cell, or natural killer cell (NK) cell]. A panel of markers is decided based on morphological differential diagnosis (no single marker is specific) which includes leukocyte common antigen (LCA), B-cell markers (CD20 and CD79a), T-cell markers (CD3 and CD5).LCA is used to classify the NHL to be of a particular type and to guide the treatment to be given. Knee replacement or bone grafting depends on the area of involvement. Knee replacement and arthrosis are two different procedures. If there is sufficient uninvolved bone surface to allow knee replacement then it can be done. </s>