Which Way to Choose for the Treatment of Metastatic Prostate Cancer: A Case Report and Literature Review

Abstract

Background: Prostate cancer (PCa) is the second most common cancer among males in the world and the majority of patients will eventually progress to the metastatic phase. How to choose an effective way for the treatment of metastatic PCa, especially in the later stage of the disease is still confusing. Herein we reported the case of a patient diagnosed with metastatic PCa and conducted a literature review on this issue.

Case presentation: A 57-year-old man with metastatic PCa had been managed by Dr. J.P. since April 2012 when the patient was admitted to the Third Affiliated Hospital of Sun Yat-sen University by aggravating frequent urination and dysuria. The prostate-specific antigen (PSA) concentration was 140 ng/ml, and the diagnosis of PCa was confirmed by prostate biopsy, with Gleason score 4 + 5 = 9. Chest CT and bone scan indicated multiple metastases in the lungs and bones. Triptorelin, bicalutamide, zoledronic acid, and docetaxel were then administered, six cycles later, the metastatic tumors in the lungs disappeared and those in the bones lessened significantly, along with a remarkable reduction in PSA level (< 2 ng/ml). Intermittent androgen deprivation was subsequently conducted until August 2018, when the serum PSA level was found to be 250 ng/ml, again docetaxel 75 mg/m² was administered immediately but the patient was intolerant this time. Instead, abiraterone was administered until March 2019 because of intolerable gastrointestinal side-effects and increasing PSA level. In October 2019, the patient came to our center, a modified approach of docetaxel (day 1 40 mg/m² + day 8 35 mg/m²) was administered. Luckily, the PSA level decreased rapidly, the bone pain was greatly relieved, and no obvious side effects occurred. However, four cycles later, docetaxel failed to work anymore, the metastatic tumor in the liver progressed. We proposed several regimens as alternatives, but they were soon denied due to the high prices or unavailability or uncertain effect of the drugs. In addition, the patient's condition deteriorated speedily and can no longer bear any aggressive treatment. Finally, the patient died of multiple organ failure in August 2020.

Conclusion: The experiences of this case provide valuable evidence and reference for the treatment choices of metastatic PCa, in some circumstances modified and advanced regimens may produce unexpected effects.

Keywords: case report; literature review; metastasis; prostate cancer; treatment.

Figure 1

Radiographic change pre- and post-therapy. The results of CT scan showed metastatic tumors in bilateral lungs at diagnosis (A) and no visible metastatic tumors in the lungs after androgen deprivation therapy and six cycles of chemotherapy (C); Bone scan showed multiple metastases in the scapulae, ribs, sacroiliac joints, hip joints, thoracic vertebrae, lumbar vertebrae, etc at diagnosis (B) and the metastatic tumors in the bones lessened significantly (D).

Figure 2

CT/MRI scan showed widespread metastases in the lungs (A), liver, bilateral adrenals (B), thoracic and lumbar vertebrae (C), and pelvis bones (D).

Figure 3

Histopathology of prostate and liver tumor. No visible tumor cell in prostate specimen (A), and expression of P63 (B) and 34BE12 (C) surrounding the gland. Visible prostate adenocarcinoma in liver tumor (D) with expression of AR (E), PSA (F) and negative Syn (G) and CgA (H), Hepatocyte (I).

Figure 4

Overall process of disease progression, related treatment and changes of the PSA level. The upper graph shows changes of the PSA level, the treatment course is in the middle and the progression of the disease is shown in the bottom. ADT, androgen deprivation therapy; DOC, docetaxel; IAD, intermittent androgen deprivation; ABI, abiraterone; NA, not available.