Isolated brain metastases as first site of recurrence in prostate cancer: case report and review of the literature

The Clinical, Diagnostic, Therapeutic, and Prognostic Characteristics of Brain Metastases in Prostate Cancer: A Systematic Review

AIM

Prostate cancer (PCa) is the second most common nonskin malignancy and the second most common cause of cancer-related deaths in men. The most common site of metastasis in PCa is the axial skeleton which may lead to back pain or pathological fractures. Hematogenous spread to the brain and involvement of the central nervous system (CNS) are a rare occurrence. However, failed androgen deprivation therapy (ADT) may facilitate such a spread resulting in an advanced metastatic stage of PCa, which carries a poor prognosis.

METHODS

In this systematic review, we searched the PubMed, Scopus, and Web of Science online databases based on the PRISMA guideline and used all the medical subject headings (MeSH) in terms of the following search line: ("Brain Neoplasms" OR "Central Nervous System Neoplasms") and ("Prostatic Neoplasms" OR "Prostate"). Related studies were identified and reviewed.

RESULTS

A total of 59 eligible studies (902 patients) were included in this systematic review. In order to gain a deeper understanding, we extracted and presented the data from included articles based on clinical manifestations, diagnostic methods, therapeutic approaches, and prognostic status of PCa patients having BMs.

CONCLUSION

We have demonstrated the current knowledge regarding the mechanism, clinical manifestations, diagnostic methods, therapeutic approaches, and prognosis of BMs in PCa. These data shed more light on the way to help clinicians and physicians to understand, diagnose, and manage BMs in PCa patients better.

What to Trust, PSA or [68Ga]Ga-PSMA-11: Learn from Experience

Brain metastases from prostate cancer typically occur in the more advanced stages of the disease. Clinically, the early diagnosis of visceral disease is crucial, impacting on patient’s management and prognosis. Although magnetic resonance imaging (MRI) is the modality of choice for the detection of brain metastases, it is not routinely performed in the surveillance of prostate cancer patients unless neurological manifestations appear. Prostate-specific membrane antigen (PSMA) is a glycoprotein, a membrane-bound metallopeptidase, overexpressed in more than 90% of prostate cancer cells. This molecular target is a suitable tissue biomarker for prostate cancer functional imaging. We present a case of a 73-year gentleman diagnosed with prostate adenocarcinoma and surgically treated (pT3bN1Mx, Gleason Score of 9) in February 2016. Subsequently, he underwent androgen deprivation therapy because of the occurrence of a bone metastasis. Between 2016 and January 2019 PSA levels were maintained under control. Starting from September 2019, it progressively raised up to 0.85 ng/mL with a doubling time of 3.3 months. Therefore, he performed a [⁶⁸Ga]Ga-PSMA-11 PET/CT which showed a focal radiopharmaceutical uptake in the right temporal lobe corresponding to the presence of a rounded cystic lesion on brain MRI. The subsequent excisional biopsy diagnosed a prostate adenocarcinoma metastasis. PSMA expression has been reported in brain parenchyma after ischemic strokes and in some brain tumors including gliomas, meningiomas, and neurofibromas. In our case, the lack of symptoms and the relatively low PSA level raised questions about the nature of the lesion, posing the differential diagnosis between brain metastases and primary brain tumor. Finally, our case shows the capability of [⁶⁸Ga]Ga-PSMA-11 PET/CT to detect metachronous distant brain metastases in a low biochemical recurrent asymptomatic prostate cancer patient, indicating that proper acquisition – from the vertex to thigh – should be always considered, regardless of the PSA level.

Metastatic prostatic adenocarcinoma to the brain and spinal cord: a contemporary clinicopathologic analysis of 30 cases

Metastatic prostatic adenocarcinoma (PCa) to lymph nodes and bone is well documented in the literature, however only case reports and small series of metastatic PCa to the brain and spinal cord with clinicopathologic analysis have been published. We identified 30 cases of metastatic PCa to the brain and spinal cord. The mean patient age was 67 years (range: 50 to 87 years). Thirteen (43%) cases involved the brain and 17 (57%) cases involved the spinal cord. Most of the cases (60%) were a single mass. Of the 13 cases involving the brain, the temporal lobe 6 (46%) was the most common site and the spinal cord lesions involved the thoracic region in 13/17 (76%) cases. All patients had one or more metastases to other organs. In 8 patients, the brain or spinal cord metastasis was the initial diagnosis of PCa. In the patients that had prior prostate biopsy specimens available, the Gleason score ranged from 3+3=6 (Grade group 1: indicating unsampled higher grade PCa) to Gleason score 4+5=9 (Grade group 5). Follow-up was available in 21 cases with a mean duration of 20 months (range: 1 to 130 months). This is one of the largest clinicopathologic studies to date of metastatic PCa to the brain and spinal cord. Although rare, metastatic PCa should be considered in the differential diagnosis of a solitary brain or spinal cord mass in male patients, even over a decade after the initial diagnosis of PCa.

Neurologically asymptomatic cerebral oligometastatic prostate carcinoma metastasis identified on [Ga]Ga-THP-PSMA PET/CT

Background

Brain metastases from prostate cancer are rare and usually only occur in the context of widespread systemic disease. This is the first case report of a solitary brain oligometastasis, in a neurologically intact prostate cancer patient with no other systemic disease, detected using [⁶⁸Ga]Ga-THP-PSMA PET/CT and only the second one using a PSMA-based radiopharmaceutical.

Case presentation

We report the case of a prostate cancer patient presenting 5 years after robot-assisted laparoscopic prostatectomy with biochemical recurrence, no neurological symptoms, and in the absence of metastatic lesions in the body on conventional imaging. A solitary cerebral metastasis was detected using [⁶⁸Ga]Ga-THP-PSMA PET/CT, surgically resected, leading to a drop in serum PSA and a good recovery.

Conclusion

In this case, [⁶⁸Ga]Ga-THP-PSMA PET/CT resulted in a major change in clinical management and avoided additional morbidity associated with delayed diagnosis and treatment. This report demonstrates the importance of considering the presence of metastatic disease outside the conventional locations of prostate cancer spread, as well as the importance of ensuring comprehensive [⁶⁸Ga]Ga-PSMA PET/CT coverage from vertex to upper thighs.

Malignant invasion of the central nervous system: the hidden face of a poorly understood outcome of prostate cancer

Malignancies of the central nervous system include primary brain tumors and brain metastases, the latter being the major cause of intracranial neoplasms in adults. Although prostate cancer (PCa) brain metastases are not the most common source, recent data show that the relevance of prostate cancer brain metastases (PCBM) cannot be neglected. In this review, we focus on the molecular repertory as well as on the phenotypical similarities between PCBM and primary PCa, such as the cellular evolution and the maintenance of androgen-receptor expression. Moreover, the simultaneous occurrence of PCBM with other PCa metastatic sites and the significance of the clinical heterogeneity of the disease are also discussed. In addition, a potential relationship between the heterogeneous behavior exhibited by PCBM and the co-occurrence of malignant cell clusters with distinct genetic profiles is also hypothesized, as well as the prominent role of astrocytes in the establishment of PCBM.

Prostate adenocarcinoma metastases to the testis and brain: case report and review of the literature

Prostate cancer is the second most common cancer in men worldwide. While clinicians commonly see metastases to the bones and lymph nodes, it may infrequently spread to more uncommon locations. We report an unusual case of an 83-year-old patient with previously treated prostate adenocarcinoma who presents with symptomatic metastases to the testis and brain in the absence of widely disseminated disease. This case report highlights the importance of including metastatic disease in the differential for patients with a history of prostate cancer and a newly discovered mass until an evaluation of the tissue can be performed.