Serum vitamin B12 and transcobalamin abnormalities in patients with cancer

Abstract

One hundred and thirty-nine patients with non-hematologic malignancy were studied to define the incidence of vitamin B12-related abnormalities and correlate them with clinical findings. Based on vitamin B12-binding patterns, the following relatively distinct groups were defined: (A) 50% had normal results; (B) 6% had very high transcobalamin (TC) I and vitamin B12 levels as reported in isolated instances previously: most had hepatic metastases and early death, and all had definite metastatic disease; (C) 11% had high vitamin B12 levels with little or no unsaturated TC I elevation: most also had hepatic and other metastases and early death; (D) 23% had high vitamin B12-binding capacity with normal TC I and vitamin B12 levels: there were no distinguishing features for this group other than an increased proportion of black patients; and (E) 10% had low vitamin B12 levels, in many cases not associated with vitamin B12 deficiency or other known causes of low serum levels. Thus, high serum vitamin B12 level, with or without unsaturated TC I elevation, usually implies a poor prognosis in a patient with cancer. However, while most such patients have hepatic and other metastases, hepatic involvement was not universal nor did most patients with hepatic disease have high vitamin B12 levels. High serum TC I thus is not always due to increased granulocytic proliferation or to hepatic tumor, and alternative mechanisms for TC I accumulation should be sought.

Hyperhomocysteinaemia and immune activation in patients with cancer

“…Interestingly, vitamin B 12 concentrations were also associated with the prognosis, although it was higher concentrations of vitamin B 12 that were associated with progressive tumour disease. This result seems surprising at first glance, but agrees with earlier data for a smaller population, in which higher concentrations of vitamin B 12 were related to a poor prognosis in patients with cancer (40). Tumour progression can of course be monitored according to more specific classifications, but the classification used in our study allowed the comparison of patients with different types of tumours.…”

Tumor Imaging in Patients with Advanced Tumors Using a New 99mTc-Radiolabeled Vitamin B12 Derivative

“…Using immunohistochemistry, we have shown an increased expression of haptocorrin in samples from patients with carcinomas of the lung, prostate, uterus, and ovary as well as squamous cell carcinomas of the skin, B-cell lymphomas, seminomas, anaplastic thyroid cancer, and bladder urothelial cancer (15). The results support and expand earlier studies on plasma levels of haptocorrin, where high levels have been encountered in patients with liver cancer and with chronic myeloid leukemia and also in patients displaying normal levels of transcobalamin (16,17).…”

Unexpected high plasma cobalamin/Proposal for a diagnostic strategy

“…In addition to liver cancer, high levels of plasma Cbl has been reported sporadically in patients with lung [ 31 ], breast [ 31 ], gastrointestinal [ 3 , 31 , 32 ] and renal cancer [ 33 ]. Since HC is synthesised by all of these tissues [ 34 ], a plausible explanation for the elevated Cbl levels is an increased release of HC to the circulation.…”