Apolipoprotein (apo) B, the critical structural protein of the atherogenic lipoproteins, has two major isoforms: apoB48 and apoB100. ApoB48 is found in chylomicrons and chylomicron remnants with one apoB48 molecule per chylomicron particle. Similarly, a single apoB100 molecule is contained per particle of very-low-density lipoprotein (VLDL), intermediate density lipoprotein, LDL and lipoprotein(a). This unique one apoB per particle ratio makes plasma apoB concentration a direct measure of the number of circulating atherogenic lipoproteins. ApoB levels indicate the atherogenic particle concentration independent of the particle cholesterol content, which is variable. While LDL, the major cholesterol-carrying serum lipoprotein, is the primary therapeutic target for management and prevention of atherosclerotic cardiovascular disease, there is strong evidence that apoB is a more accurate indicator of cardiovascular risk than either total cholesterol or LDL cholesterol. This review examines multiple aspects of apoB structure and function, with a focus on the controversy over use of apoB as a therapeutic target in clinical practice. Ongoing coronary artery disease residual risk, despite lipid-lowering treatment, has left patients and clinicians with unsatisfactory options for monitoring cardiovascular health. At the present time, the substitution of apoB for LDL-C in cardiovascular disease prevention guidelines has been deemed unjustified, but discussions continue.

Sjogren’s Disease (SjD) is associated with an increased risk of lymphoma. We investigated the prevalence of lymphoma in a retrospective case series of patients with SjD and reported on the clinical presentation, treatment, response, and outcome. A retrospective review of 132 patients diagnosed with Sjogren’s Disease was conducted at our institution from June 2000 to November 2023, and 10 cases of malignant lymphoma were identified. Clinical and biological markers known to be predictors of lymphoma, as well as lymphoma characteristics, were examined. The most common predictive lab findings were hypergammaglobulinemia, the rheumatoid factor, and lymphopenia. Persistent parotid gland enlargement was also found in greater than 50% of patients. The majority of patients were Caucasian females, and the average time between the diagnosis of SjD and lymphoma was 14.3 years. The median age at lymphoma diagnosis was 59.5 years, with 9 out of 10 lymphomas identified as non-Hodgkin lymphoma, the majority of cases being mucosa-associated lymphoid tissue (MALT) lymphoma. We identified similarities in our series, such as laboratory markers and clinical symptoms, to those previously identified as possible predictors of lymphoma development. These factors may be useful in determining the risk of malignancy development and justify the need for long-term monitoring, as well as provider education and awareness.