Diffuse large B-cell lymphoma (DLBCL) presenting with hyperlactatemia or lactic acidosis (LA) represents a rare, often fatal paraneoplastic phenomenon driven by tumor metabolism rather than hypoperfusion. This condition, classified as Type B LA, is frequently misdiagnosed as septic shock due to overlapping clinical features, leading to delayed oncologic intervention. A detailed analysis of two clinical cases combined with a systematic review of 19 published studies reveals critical prognostic thresholds: initial lactate levels between 5–14.9 mmol/L confer a significant survival advantage over levels of 15–24.9 mmol/L, and peak lactate concentration inversely correlates with survival time. Crucially, early initiation of chemotherapy-based regimens, rather than supportive care alone, significantly improves outcomes (P=0.026), establishing LA as an oncologic emergency requiring immediate hematologic workup. Adjunctive therapies, including sodium bicarbonate for severe acidemia and thiamine/Vitamin B supplementation to support mitochondrial function, may provide additional benefit, while medications exacerbating lactate production must be avoided.
The pathophysiology underlying this metabolic crisis is primarily attributed to the Warburg effect, wherein lymphoma cells exhibit aerobic glycolysis, consuming massive amounts of glucose and converting it to lactate even in oxygen-rich conditions. This metabolic reprogramming is not merely a bystander effect but a hallmark of aggressive tumor biology, driven by oncogenic signaling pathways that upregulate lactate dehydrogenase (LDH) and glucose transporters. The resulting lactate-rich microenvironment further promotes tumor proliferation, angiogenesis, and immunosuppression, creating a vicious cycle. High tumor burden, particularly hepatic infiltration, exacerbates the condition by impairing the liver's capacity for gluconeogenesis and lactate clearance, often co-presenting with hypoglycemia. This metabolic profile explains why patients can appear floridly septic without an infectious source, as the lymphoma itself acts as a metabolically active "lactate factory."
Diagnostically, the emergence of unexplained LA in a patient with or without a known lymphoma diagnosis should trigger immediate investigation for an underlying hematologic malignancy. Key differential indicators include a discrepancy between the severity of acidosis and the patient's hemodynamic status (e.g., well-perfused despite high lactate), concomitant cytopenias, or elevated LDH levels disproportionate to other organ injuries. Imaging may reveal hepatosplenomegaly or occult lymphomatous masses, but a high index of suspicion is necessary as presentations can be atypical, including imaging-negative infiltrative disease. Early bone marrow biopsy and flow cytometry are often diagnostic. The literature review underscores that delays in recognizing the paraneoplastic nature of the acidosis are a common theme in fatal cases, as clinicians initially attribute the findings to sepsis and delay chemotherapy.
Therapeutic strategy must pivot from a purely supportive model to an aggressive anti-neoplastic approach. The evidence strongly indicates that correcting the acidosis without addressing the tumor is futile. While sodium bicarbonate can be used as a bridge to stabilize pH and prevent cardiac complications in severe acidemia (pH <7.1), its utility is temporary and does not address the root cause. Similarly, thiamine deficiency has been implicated in some cases of refractory LA in lymphoma patients, as thiamine is a crucial cofactor for pyruvate dehydrogenase; supplementation can help restore oxidative metabolism in healthy tissues. However, the cornerstone of management is the prompt administration of cytotoxic chemotherapy (e.g., R-CHOP regimen) to debulk the tumor and halt lactate production. In the reviewed cases, patients who received early chemotherapy had markedly better survival than those managed with bicarbonate or vitamins alone.
Prognostication is heavily reliant on lactate kinetics. The analysis establishes a clear dose-response relationship between lactate levels and mortality. Patients who present with lactate levels exceeding 15 mmol/L face an almost universally poor outcome, often succumbing to multi-organ failure within days despite maximal therapy. This suggests that extreme hyperlactatemia may reflect an irreversible metabolic collapse. Conversely, patients with moderate elevation (5–15 mmol/L) who respond to initial chemotherapy with a rapid decline in lactate levels have a fighting chance, highlighting the importance of serial lactate monitoring as a dynamic biomarker of treatment response. Future directions should focus on integrating metabolic parameters into risk stratification models and exploring novel therapies that directly target tumor glycolysis, such as LDH inhibitors, to break the Warburg effect at its source.
DOI
10.1007/s11684-025-1199-2