Isolated peritoneal carcinomatosis in prostate cancer: from a successful hormonal management to a review of the literature

Abstract

Metastases from prostate cancer involve mainly the bone compartment. However, visceral metastases are found in up to 49% of metastatic patients, occurring mainly in late stages of the disease, and are correlated with poor outcome. Peritoneal carcinomatosis is rarely described in literature, particularly when not associated with other distant metastatic lesions. We present the management of a patient with prostate cancer progressing on androgen deprivation therapy with description of omental involvement on ⁶⁸Ga PSMA-PET. There was no ascite or other distant lesion, reflecting thus a specific tropism of the cancer in this patient who had no history of prostate surgery. Abiraterone acetate resulted in a long-lasting complete response. We also present a review focusing on this entity.

Keywords: case report; hormone therapy; peritoneal carcinomatosis; prostate cancer; prostate-specific membrane antigen and PET.

Figure 1.. Radiological evolution on androgen deprivation therapy.

(A) Initial abdominal CT showing locally advanced prostate cancer with bladder wall infiltration. (B) Abdominal CT after 12 months of androgen deprivation therapy, with a regression of the tumor and of the bladder infiltration. No peritoneal involvement was detected on the two CTs. CT: Computed tomography.

Figure 2.. (A) Histological diagnosis of prostate cancer adenocarcinoma Gleason 7 (4 + 3) on primary prostate cancer.

(B) Prostate adenocarcinoma on peritoneal biopsy.

Figure 3.. Axial skeletal MRI at cancer diagnosis showing no bone lesion.

Figure 4.. Pelvic MRI, performed after 12 months of androgen deprivation therapy, showing no suspect lymph node.

Figure 5.. (A) PSMA-PET showing peritoneal implant (arrow).

(B) Abdominal computed tomography that was performed on the same time and that initially misdiagnosed these peritoneal implants due to its very small size (arrow).