Multiple Primary Malignancies With Hypercalcemia Presentation: A Case Report

Multiple primary malignancies (MPMs) are defined as having more than one primary malignancy and when each tumor is histologically distinct and unrelated to the others. Multiple risk factors have been found to be associated with MPMs. These include familial syndromes, sequela from treatments of previous malignancies, and environmental factors such as smoking, alcohol consumption, obesity, and male sex. Hypercalcemia has a well-known association with malignancy and is often the first abnormality that leads to further testing. Lung cancer followed by colorectal cancer has the highest mortality of all cancers in the USA, with adenocarcinoma being the most prevalent histological subtype. Further, estimates show that those with one malignancy have a 1.29 times higher risk of developing another malignancy. Hereby, we present a case of a patient with squamous cell carcinoma of the lung who presented with hypercalcemia and incidentally was found to have another primary adenocarcinoma of the colon.