Can folate replacement induce lymphoma progression?

Abstract

A 43-year-old Japanese man with a low haemoglobin level of 1.3 g/dL and multiorgan dysfunction syndrome (MODS) was admitted to our hospital. He was diagnosed with folate deficiency, which was initially attributed to his malnutrition. He was transfused with several units of packed red blood cells and treated with folate, thiamine and vitamin B₁₂ supplements; he showed a prompt haematological response and recovery from MODS. However, 3 weeks after the initial recovery, he had a relapse of pancytopenia and developed high-grade fever along with rapidly enlarging, generalised lymphadenopathy. Bone marrow biopsy revealed hemophagocytosis, and lymph node biopsy revealed peripheral T-cell lymphoma, not otherwise specified. Folate supplementation may have promoted lymphoma progression.

Background

Folate deficiency is a cause of severe pancytopenia and predominantly occurs in patients with alcoholism and pregnant women.^{1 2} Although folate deficiency may develop in patients with inadequate food intake complicating leukaemia or lymphoma,³ such cases are either extremely rare or rarely reported. It is speculated that folate deficiency may inhibit lymphoma progression, whereas folate administration may promote its progression.⁴

Case presentation

A 43-year-old Japanese man presented with a 3-month history of walking difficulty and progressive altered mental status. Because of his altered mental status, we took his medical history from his parents, who were living with the patient. He was unemployed and had been withdrawn in his room and housebound for several years. He seldom communicated with his parents. He continued to perform his usual daily living activities. He remained in his usual state of health 3 months prior to hospital admission when he began experiencing difficulty in standing and walking; however, he was able to move all his extremities and crawl. At 2 weeks prior to admission, his speech was nonsensical and incoherent. He was in a confused state the day prior to admission and was brought in an ambulance to the emergency department of our hospital. He did not complain of headache, numbness, weakness, fever, chills or night sweats. His parents did not recognise any change in his body weight. He did not have significant medical history. He took no medications and had no allergies. He had no history of drinking alcohol, illicit drug use or tobacco use. His diet was predominantly composed of processed meat products and rarely included vegetables. His family history was non-contributory.

Investigations

On physical examination, his temperature was 37°C; blood pressure, 107/67 mm Hg; heart rate, 110 beats/min; respiratory rate, 30 breaths/min; and oxygen saturation, 99% while breathing ambient air. His height and body weight were 177 cm and 64 kg, respectively, with a Body Mass Index of 20. He was awake and alert but unable to answer questions or follow commands. His pupils were normal. The patient moved his limbs purposefully in response to noxious stimuli. Deep-tendon reflexes were normal, and plantar reflexes were normal bilaterally. The patient had pale conjunctivae and icteric sclera. His neck was supple. Both lungs were clear to auscultation. Gynecomastia or vascular spiders were not noted. Cardiac examination was normal with no jugular venous distention. His abdominal findings were normal with no evidence of hepatosplenomegaly or ascites. Rectal examination revealed guaiac-negative, brown stool. No lymph node adenopathy was noted. He did not have leg oedema.

He had severe macrocytic anaemia, azotaemia and elevated liver enzymes (table 1). His lactic acid level was high. The peripheral smear revealed macrocytosis with hypersegmented neutrophils. At admission, a chest X-ray showed no acute cardiopulmonary processes. Blood cultures were negative. CT and MRI of the head showed mild brain atrophy without any haemorrhage, infarction or mass. His CT of the chest and abdomen showed no abnormal findings with no lymph node adenopathy or hepatosplenomegaly.

Table 1.

Laboratory data

Variable	Reference range	On admission
Haematocrit (%)	40–48	3.8
Haemoglobin (g/dL)	14–18	1.3
White cell count (× 10^9/L)	4–8	1.4
Differential count (%)
Neutrophil	45–55	88
Lymphocyte	25–40	10
Monocytes	4–6	0.5
Eosinophils	0–5	1
Platelet count (× 10^9/L)	150 –350	11
Mean corpuscular volume (fL)	82–92	119
Mean corpuscular haemoglobin (pg/red cell)	27–32	41
Mean corpuscular haemoglobin concentration (g/dL)	32–36	34
Reticulocyte (%)	0.2–1.5	11.7
Prothrombin time (%)	80–100	21
Prothrombin time international normalisation ratio	0.9–1.1	2.0
Activated partial thromboplastin time (s)	<35	31.7
Blood urea nitrogen (mg/dL)	8–22	60
Creatinine (mg/dL)	0.6–1.0	1.5
Glucose (mg/dL)	70–109	100
Sodium (mEq/dL)	138–146	144
Potassium	3.6–4.9	4.9
Chloride	99–109	94
Bicarbonate (mEq/dL)	23–25	6
Total protein (g/dL)	6.7–8.3	7.0
Albumin (g/dL)	3.1–5.1	3.8
Aspartate aminotransferase (U/L)	13–33	337
Alanine aminotransferase (U/L)	8–42	257
Alkaline phosphatase (U/L)	115–359	213
Total bilirubin (mg/dL)	0.2–1.2	6.4
Direct bilirubin (mg/dL)	0.1–0.6	4.4
γ-Glutamyltransferase (U/L)	10–47	13
Lactate dehydrogenase (U/L)	119–229	1921
Lactic acid (mg/dL)	<15	115
Folic acid (ng/mL)	2–20	0.5
Vitamin B12 (pg/mL)	200–900	309
Thiamine (ng/mL)	24–66	<5
Haptoglobin (mg/dL)	25–176	<10
Direct Coombs antibody	Negative	Negative
Indirect Coombs antibody	Negative	Negative
Ferritin (ng/mL)	21–274	831
Rapid plasma regain	Negative	Negative
Treponemal haemagglutination	Negative	Negative
HIV antibody	Negative	Negative
Hepatitis B virus surface antigen	Negative	Negative
Hepatitis C antibody	Negative	Negative
Antinuclear antibody	<1:40	<1:40

Differential diagnosis

He had slowly progressive weakness and altered mental status with severe anaemia and lactic acidosis. Before thiamine and folic acid levels were obtained, we performed a differential diagnosis of pancytopenia with altered mental status, for which parameters such as vitamin B₁₂ and folate deficiencies, autoimmune haemolytic anaemia (AIHA), hereditary spherocytosis and cold haemagglutinin disease resulting either from infections or lymphomas were tested (table 1). We also considered leukaemia as a cause of pancytopenia. We did not find any evidence of infection by CT or blood culture. Negative Coombs tests made AIHA unlikely. His bone marrow biopsy result on hospital day 4 was normal. Ultimately, he was diagnosed with folate and thiamine deficiency based on their low serum levels. Increased level of serum lactic dehydrogenase (LDH) and indirect bilirubin as well as decreased level of haptoglobin supported ineffective haematopoiesis due to folate deficiency. Although serum vitamin B₁₂ level was at the lower limit of the normal range, vitamin B₁₂ deficiency was still likely. He occasionally had incoherent speech even after his consciousness improved after thiamine replacement. Although severe anaemia may have contributed to his decreased consciousness, his symptoms and laboratory results confirmed the diagnosis of Wernicke encephalopathy as well.

Treatment

Several units of packed red blood cells were transfused and 5 mg/day of oral folate, 100 mg/day of intravenous thiamine and 1 mg/day of intravenous vitamin B₁₂ supplements were administered. The patient exhibited a prompt haematological response. His serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin, LDH and lactate levels normalised. His muscle strength and instability improved. He was able to walk but still with mild instability. His altered mental status improved; however, he still occasionally had incoherent speech.

Outcome and follow-up

After 3 weeks of the initial recovery period, white blood cell, haemoglobin and platelet counts began to decrease again while continuing vitamin B₁₂ and folate supplement administration. Meanwhile, the patient developed high fever, jaundice and rapidly enlarging, generalised lymphadenopathy for a week, with rubbery, mobile and non-tender lymph nodes measuring 1.5–2 cm in diameter.

Repeated laboratory tests revealed markedly elevated ferritin levels, soluble CD25, AST, ALT, bilirubin and LDH. CT of the abdomen showed hepatosplenomegaly and systemic lymph node enlargement. Repeated bone marrow biopsies revealed hemophagocytosis (figure 1). Based on these findings, lymphohistiocytosis (HLH) was diagnosed.⁵ Serological tests for Epstein-Barr virus (EBV) and cytomegalovirus indicated they were not the likely cause of HLH. Lymph node excisional biopsy was performed from the inguinal area. The pathology of the lymph node demonstrated atrophic follicles, histiocyte infiltration and diffuse proliferation of small to medium-sized abnormal lymphocytes with irregular nuclear contours. Immunostaining of the abnormal lymphocytes was positive for CD3, CD4 and CD5. EBV encoded RNA in situ hybridisation, CD7, CD10 and CD30 were negative (figure 2). Flow cytometry was positive for CD2, CD3, CD4, CD5 and CD7, and negative for CD10, CD16, CD19, CD25, CD30, CD34 and CD56. A serological test of human T-cell leukaemia virus type 1 antibody was negative. The patient was diagnosed with peripheral T-cell lymphoma, not otherwise specified. After the diagnosis, supplementation of folic acid, vitamin B₁ and vitamin B₁₂ were discontinued. His lymphoma as well as the HLH were resistant to multiple chemotherapies, including one cycle of CHOP therapy (cyclophosphamide 750 mg/m² 1 day, doxorubicin 50 mg/m² 1 day, vincristine 1.4 mg/m² 1 day, prednisolone 60 mg/m² 5 days), CHP (cyclophosphamide 750 mg/m² 1 day, doxorubicin 50 g/m² 1 day, prednisolone 60 mg/m² 5 days) and two cycles of DeVIC (dexamethasone 40 mg/body 3 days, etoposide 100 mg/m² 3 days, ifosfamide 1500 mg 3 days, carboplatin 300 mg/m² 1 day). He died 5 months after the lymphoma diagnosis.

Figure 1.

Bone marrow films (Wright-Giemsa stain) on second admission. The bone marrow was hypocellular with increased activated histiocytes in number (A, ×100). There were hemophagocytes containing phagocytosed blood cells especially erythrocytes within the cytoplasm (B, C, ×400).

Figure 2.

H&E stain (A) of lymph node sample shows extensive proliferation of small to medium-sized abnormal lymphocytes. H&E stain (A) and the immunohistochemical expression of CD68 (H) show histiocyte infiltration without hemophagocytosis. The immunostains demonstrate the abnormal lymphocytes to be CD3⁺, CD5⁺, CD7⁻, CD4⁺ and CD8⁻, without EBV encoded RNA in situ hybridisation (EBER-ISH) positive cells (B–G).

Discussion

We report a case of severe pancytopenia due to folate deficiency associated with multiorgan dysfunction, which was diagnosed as peripheral T-cell lymphoma, soon after folate and thiamine supplementation.

There are multiple case reports of folate deficiency as a cause of severe pancytopenia, with most cases occurring in patients with alcoholism and pregnant women.^{1 2} The cause of folate deficiency in our case was likely poor dietary intake because the patient only consumed processed meats that had low folate levels. Although folate deficiency may develop in patients with leukaemia or lymphoma,³ such cases are extremely rare or rarely reported. Folic acid is a cofactor for various methyltransferases that participate in purine synthesis, and consequently in DNA synthesis (figure 3).⁶ Rapidly proliferating cancer cells have accelerated DNA synthesis and therefore increasingly require folate.⁴ Tumour cells also display increased folate catabolism rates. Patients with cancer with active, untreated or metastatic malignancies exhibit folate deficiency without evidence of malnourishment, malabsorption or increased intact folate excretion.⁷ Underlying malignant lymphoma might possibly be another cause of folate deficiency.

Figure 3.

Overview of folate-metabolising and methionine-metabolising pathways. dUMP, deoxyuridine monophosphate; dTMP, deoxythymidine monophosphate; MTHFR, methylene tetrahydrofolate reductase; MS, methionine synthase; THF, tetrahydrofolate; SAM, S-adenosyl methionine; SAH, S-adenosyl homocysteine. Reproduced from Matsuo et al with permission.⁶

High-folate doses in well-established cancers may lead to accelerated proliferation, whereas folate deprivation leads to reduced or delayed growth and is the basis for antifolate cancer therapy development.⁴ Because cancer cells, similar to all cells, synthesise DNA during mitosis, they require a folate supply. Supplying cancer cells with additional folate may promote their proliferation; thus, it is concerning that increased folate intake due to folic acid fortification of foodstuffs and folate supplement consumption may promote existing neoplasms. However, the role of folate in cancer development and progression remains highly controversial.⁸ Folate supplementation promoted mammary tumour progression in a rat model.⁹ High-folate levels likely have tumour-promoting effects in other organs, especially the colorectum and prostate, thereby causing colorectal adenomas and prostate cancer.^{10 11}

Our patient also exhibited thiamine deficiency. Thiamine is a water-soluble vitamin stored primarily in the liver that is exhausted within 18 days after cessation of dietary thiamine absorption.¹² Thiamine deficiency can be caused by malnutrition or a diet comprising thiaminase-rich foods (raw freshwater fish, raw shellfish, ferns) and/or antithiamine factor-rich foods (tea, coffee, betel nuts) and by grossly impaired nutrition associated with chronic diseases, namely alcoholism, gastrointestinal diseases, HIV infection and persistent vomiting.¹³ Reductions in peripheral thiamine or thiamine pyrophosphate level may be because of extensive accumulation and/or use by cancer cells.¹⁴ An unbalanced diet as well as an underlying malignant lymphoma might be a cause of thiamine deficiency in our case. Metabolic studies have provided strong evidence that cancer cells exploit thiamine-dependent enzymes and pathways for anabolic, proliferative and survival purposes, but how thiamine supplementation impacts the metabolic phenotype of cancer cells remains hypothetical and warrants extensive research.¹⁴ A previous study revealed that thiamine supplementation in a tumour mouse model had statistically significant effects on tumour growth compared with non-supplemented controls.¹⁵

In our case, folate and thiamine deficiencies likely inhibited lymphoma progression, whereas folate and thiamine administration promoted it. At admission, the patient had unremarkable lymph nodes and a normal marrow biopsy, which subsequently evolved into pathological enlargement and abnormal histological changes after folate and thiamine administration. To our knowledge, this is the first reported case of folate and thiamine supplementation associated with lymphoma progression.

Learning points.

• Lymphoma can be a cause of folate deficiency.

• Lymphoma progression might be promoted by folate and thiamine supplements.

• We need to consider malignancy, especially malignant lymphoma, as an underlying cause of pancytopenia when lymph node adenopathy develops shortly after folate and thiamine deficiencies.