Our patient's serum IgG4 results were within reference range despite diagnostic immunohistochemical findings, highlighting the need for immunohistochemical review even when pathology findings are nondiagnostic. Notably, the patient’s erythrocyte sedimentation rate was moderately elevated; however, the C-reactive protein was within normal limits, and complete blood count parameters demonstrated only mild anemia without leukocytosis, suggesting that the ESR elevation was nonspecific, potentially influenced by non-inflammatory factors, and offered little in terms of diagnostic direction. Here, CRP is linked to anemia (phenotype).