David Fajgenbaum, MD, MBA, MSc: Pathology Report Findings

What are the relevant findings from her pathology report?

On excisional biopsy, this patient’s lymph nodes were found to have atrophic or regressed germinal centers, plasmacytosis, hypervascularization, and occasional hyperplastic germinal centers. This constellation of features is consistent with a disease called Multicentric Castleman Disease. You would call this patient the plasmacytic subtype, and that’s because there’s sheet-like plasma cells all throughout the lymph node which is really something that you see in Multicentric Castleman Disease and a few other inflammatory disorders.

Now, when you see these features you can’t with certainty say that this is definitely Multicentric Castleman Disease because these particular features, this constellation, can also be seen in other diseases. It can be seen in lymphomas. It can also be seen in autoimmune diseases.

Now that you have a lymph node consistent with Multicentric Castleman Disease, there’s really 2 important steps. The first is to perform LANA-1 staining to determine if this lymph node, is it HHV-8-positive or HHV-8-negative, what we call idiopathic. That’s the first step. The second step, whether it’s positive or negative, is you need to make sure to rule out the other diseases that can mimic it. If it’s a positive LANA-1 stain, it’s less likely that there’s something else but if it’s a negative LANA-1 stain, you need to do additional stainings to look for Hodgkin’s lymphoma. You need to do additional systemic laboratory evaluation for autoimmune diseases.

Multicentric Castleman Disease: Case 1

Mary is a 13-year old female who presents with a 10-month history of night sweats, fatigue, and weight loss. She presents to urgent care with complaints of flu-like symptoms. Her physical exam is notable for bilateral cervical lymphadenopathy (1-2 cm), mild splenomegaly, and mild edema. She has no neuropathy and no joint pain. She is referred to a hematologist to rule out lymphoma. Her medical history is unremarkable. Her family history is relevant for a mother with systemic lupus erythematous and father who died from colon cancer at 65 years old.

At the hematology office, the following laboratory abnormalities are noted:

• Anemia (Hgb 11 gm/dL), elevated CRP (35mg/L) and ESR (80mm/hr), elevated platelets (400,000/mK), Igs (IgG: 4500 mg/dL, IgM: 1500mg/dL, IgA: 300mg/dL).
• Negative ANA, negative dsDNA, anti-Smith and anti-phosholipid antibodies; monospot negative.
• PET scan showed generalized lymphadenopathy with a maximum SUV of 4.5; FNA of the Lymph node is uninformative. She was referred to a general surgeon for excisional lymph node biopsy.