A young merchant navy officer with night sweats, fever, and weight loss

A 31-year-old man presented with severe fatigue, unintentional weight loss (approximately 20 kg) over the last 6 months, and profuse night sweats with fever. He worked as a merchant navy officer and was also involved in the family company dedicated to the production of fruits and vegetables. His medical history was unremarkable. Physical examination no revealed cervical, axillary, or inguinal lymphadenopathy. Laboratory evaluation demonstrated a hemoglobin level of 10.3 g/dL and a platelet count of 1,000,000/µL. Infectious tests (Salmonella paratyphi, Brucella, Leishmania) and Quantiferon were negative. Computed tomography scan of the chest, abdomen, and pelvis documented the presence of mild ascites and mesenteric lymph node enlargement, without any significant abdominal mass. The appendix was not visible. Magnetic resonance imaging of the abdomen revealed a solid tissue with a pseudonodular aspect in all peritoneal spaces, more evident in the peri-hepatic and peri-splenic regions and among the intestinal loops. Explorative laparoscopy showed that the small bowel was packaged in adhesions and covered by fibrin. The parietal peritoneum presented some nodularities as friable bulges, which were sent for histological examination, as shown in Figure 1. The presence of hemorrhagic ascites was discovered, and the ascitic fluid was sent for cytological and bacteriological examination. What’s your diagnosis? A. Peritoneal lymphomatosis B. Peritoneal diffuse hyperplasia C. Malignant mesothelioma D. Pseudomixoma periton