Dual malignancies: Do they have a worse prognosis than their individual counterparts

Abstract

Background: The incidence of multiple primary cancers is reported to be between 0.734% and 11.7%. The occurrence of another malignancy of different organ in patients with known malignant tumor is known as double malignancy and is categorized into synchronous; in which the cancer occurs at the same time or within 6 months and metachronous; in which cancer follows in sequence more than 6 months apart. We review the presentation and management of synchronous malignancies in two different organs. Patients and Methods: All the patients who underwent surgery for malignancy between July 2009 and July 2013 were reviewed and the patients who had synchronous malignancies were identified. Their clinical presentation, treatment and outcome were evaluated. Results: Out of a total of 286 patients with malignancies treated in our institute, four had synchronous primary malignancies (1.39%). Three of them underwent surgery simultaneously for both the malignancies and were given adjuvant chemotherapy. One patient presented with colonic obstruction due to sigmoid carcinoma which was operated in an emergency setting and was later in the postoperative period found to have a synchronous periampullary carcinoma. Two of the patients who were managed with surgery followed by chemotherapy are doing well. Whereas the other two patients have died. Conclusion: Treatment strategies in cases of double malignancy depend on treating the malignancy that is more advanced first, or sometimes both malignancies could be treated simultaneously. If both are amenable to surgical resection as in two of our cases both the malignancies may be dealt with at the same time. The prognosis of the patients with dual malignancies depends on the aggressiveness and the stage of presentation of the more advanced tumor.