Quadruple Multiple Primary Malignancies: Early Detection of Second Primary Malignancy by Esophagogastroduodenoscopy/Colonoscopy Is Crucial for Patients with Classic Kaposi’s Sarcoma

Currently, Kaposi's sarcoma (KS) is treated following the recommendations of international guidelines. These guidelines recommend esophagogastroduodenoscopy/colonoscopy for detecting multicentric KS of visceral lesions. Second primary malignancies (SPMs) are also a common KS complication; however, information on their detection and treatment is unfortunately not yet indicated in these guidelines. This paper reports on an 86-year-old man who suffered from quadruple primary malignancies: skin classic KS with colon adenocarcinoma, oral squamous cell carcinoma (maxilla), and well-differentiated stomach adenocarcinoma. Gastric cancer was incidentally detected during esophagogastroduodenoscopy, which was performed to detect visceral KS. We suggest that esophagogastroduodenoscopy/colonoscopy be routinely performed during the follow-up of patients with KS. As SPMs are crucial complications in patients with KS, these malignancies should be detected as early as possible.