Extramedullary plasmacytoma involving the penis is extremely rare. Here, we describe a case of primary extramedullary plasmacytoma of the penis in a 64-year-old man who presented with a palpable penile mass. Nuclear magnetic resonance imaging revealed the presence of a large, round non-encapsulated mass in the perineum. A contrast-enhanced computed tomography scan of the pelvis showed that the mass was located in the tunica albuginea and corpora cavernosa at the base of the penis. The mass encased the urethra and demonstrated no marked enhancement during the arterial phase. The patient underwent successful surgical resection of the tumor. Histologically, the tumor was composed primarily of neoplastic plasma cells that were positive for CD38, vimentin and Ki 67. Postoperatively, the patient recovered well and exhibited no evidence of development of multiple myeloma, local recurrence or distant metastasis at 2 months post-surgery. To the best of our knowledge, our case represents the first documented case of human primary extramedullary plasmacytoma of the penis.

BACKGROUND Multiple primary malignant tumors are two or more malignancies in an individual without any relationship between the neoplasms. In recent years, an increasing number of cases have been reported. However, concomitant primary gastric and pancreatic cancer reported a relatively small incidence, involving no pancreatic acinar cell carcinoma reports. Here, we present the first case of concomitant pancreatic acinar cell carcinoma and gastric adenocarcinoma. CASE SUMMARY A 69-year-old male presented to our department with a history of vomiting, epigastric pain, and weight loss. Imaging revealed space-occupying lesions in the stomach and the tail of the pancreas, respectively. The patient underwent laparoscopic radical gastrectomy and pancreatectomy simultaneously. The pathologies of surgical specimens were completely different: The resected gastric specimen was moderate to poorly differentiated adenocarcinoma, whereas the pancreatic tumor was consistent with acinar cell carcinoma. The patient was treated with six cycles of oxaliplatin and S-1 chemotherapy. As of March 2021, the patient was healthy without any recurrence or metastasis. After thoroughly reviewing the literature on simultaneous pancreatic and gastric cancers at home and abroad, we discussed the clinical characteristics of these rare synchronous double cancers. Most of the cases had undergone surgery and adjuvant chemotherapy, and all of the cases were pathologically confirmed by the postoperative specimen. CONCLUSION Synchronous pancreatic acinar cells and gastric adenocarcinoma can occur and should be considered when tumors are found in these organs.

Background: Multiple primary malignant tumors are two or more malignancies in an individual without any relationship between the neoplasms. In recent years, increasing number of cases have been reported. However, Synchronous double primary gastric cancer and pancreatic acinar cell carcinoma are relatively rare to be reported. Further, most pancreatic tumors are consistent with pancreatic ductal adenocarcinomas, and other histologies are rare. We present the first case of synchronous pancreatic acinar cell adenocarcinoma and gastric adenocarcinoma.Case presentation: A 69-year-old man came to our department with a history of vomiting, epigastric pain, and weight loss. Imaging revealed space-occupying lesions in the stomach and the tail of the pancreas, respectively. The patient underwent laparoscopic radical gastrectomy and pancreatectomy simultaneously. The pathologies of surgical specimens were completely different: the resected gastric specimen was a moderate to poorly differentiated adenocarcinoma, whereas the pancreatic tumor was consistent with acinar cell carcinoma. The patient was treated with six cycles of oxaliplatin and S-1 chemotherapy. As of March 2021, the patient was healthy without any recurrence or metastasis. After reviewing lots of literatures on simultaneous pancreatic and gastric cancers at home and abroad, we discuss the clinical characteristics of these rare synchronous double cancers. Most of the cases had undergone surgery and adjuvant chemotherapy, and all of the cases were pathologically confirmed by postoperative specimen. Conclusions: Synchronous pancreatic acinar cell and gastric adenocarcinoma can occur and should be considered when tumors are found in these organs.