Clinicopathological analysis of patients with dual malignancies: A retrospective study

This study aims to report the increasing incidence of second primary malignancies to better understand the association of multiple primary cancers and the duration of their occurrence. Keeping in view the current trends in dual malignancies and to further emphasize the importance of screening and follow-up diagnosis, we reviewed the records of patients who were diagnosed with dual malignancies.

This is a retrospective observational study. We collected data from the hospital database, of patients presenting with either histologically proven synchronous or metachronous double primaries between January 1, 2017, and December 31, 2021. The time interval to differentiate between synchronous and metachronous has been taken as 6 months.

During the period of five years, twenty-three patients presented with dual malignancy. Out of 23 cases, seven were synchronous (30.43%), and 16 were metachronous (69.56%). In the synchronous malignancy group, the most common site of first and second primary malignancy was breast [5 cases (71.4%) and 3 cases (42.8%), respectively]. In the metachronous malignancy group, the most common site of the first primary was breast (7 cases; 43.75%), followed by the head and neck (4 cases; 25%), and the most common site of the second primary was also the breast (6 cases; 37.5%), followed by the lung (5 cases; 31.25%).

Second primary malignancies are not rare and can occur at any age. Regular follow-up and screening procedures by the treating oncologist can play a major role in early detection followed by appropriate treatment of second primary tumors.