A Novel Radiographic Pattern Related to Poor Prognosis in Patients with Prostate Cancer with Metastatic Spinal Cord Compression

Background: Prostate cancer spinal bone metastases can have a radiographic pro-file that mimics multiple myeloma.Objective: To analyse the presence and prognostic value of myeloma-like prostate cancer bone metastases and its relation to known clinical, molecular, and morpho-logical prognostic markers.Design, setting, and participants: A cohort of 110 patients with prostate cancer who underwent surgery for metastatic spinal cord compression (MSCC) was analysed. Spinal bone metastases were classified as myeloma like (n = 20) or non-myeloma like (n = 90) based on magnetic resonance imaging prior to surgery. An immunohis-tochemical analysis of metastasis samples was performed to assess tumour cell proliferation (percentage of Ki67-positive cells) and the expression levels of prostate-specific antigen (PSA) and androgen receptor (AR). The metastasis sub-types MetA, MetB, and MetC were determined from transcriptomic profiling.Outcome measurements and statistical analysis: Survival curves were compared with the log-rank test. Univariate and multivariate Cox proportional hazard models were used to assess the effects of prognostic variables. Groups were compared using the Mann-Whitney U test for continuous variables and the chi-square test for categorical variables.Results and limitations: Patients with the myeloma-like metastatic pattern had med-ian survival after surgery for MSCC of 1.7 (range 0.1-33) mo, while the median sur-vival period of those with the non-myeloma-like pattern was 13 (range 0-140) mo (p < 0.001). The myeloma-like appearance had an independent prognostic value for the risk of death after MSCC surgery (adjusted hazard ratio 2.4, p = 0.012). Postoperative neurological function was significantly reduced in the myeloma-like group. No association was found between the myeloma-like pattern and morpholog-ical markers of known relevance for this patient group: the transcriptomic subtypes MetA, MetB, and MetC; tumour cell proliferation; and AR and PSA expression.Conclusions: A myeloma-like metastatic pattern identifies an important subtype of metastatic prostate cancer associated with poor survival and neurological out-comes after surgery for MSCC.Patient summary: This study describes a novel radiographic pattern of prostate can-cer bone metastases and its relation to poor patient prognosis.(c) 2022 The Author(s). Published by Elsevier B.V. on behalf of European Association of Urology. This is an open access article under the CC BY license (http://creativecommons. org/licenses/by/4.0/).

Automated summary

This study explores the presence and prognostic value of myeloma-like prostate cancer bone metastases and its relation to clinical, molecular, and morphological prognostic markers. The myeloma-like metastatic pattern is associated with poor survival and neurological outcomes after surgery for metastatic spinal cord compression.