Oligometastatic Prostate Adenocarcinoma. Clinical-Pathologic Study of a Histologically Under-Recognized Prostate Cancer

Abstract

The clinical parameters and the histological and immunohistochemical findings of a prospective protocolized series of 27 prostate carcinoma patients with oligometastatic disease followed homogeneously were analyzed. Lymph nodes (81.5%) and bones (18.5%) were the only metastatic sites. Local control after metastatic directed treatment was achieved in 22 (81.5%) patients. A total of 8 (29.6%) patients developed castration-resistant prostate cancer. Seventeen (63%) patients presented with non-organ confined disease. The Gleason index 8–10 was the most frequently observed (12 cases, 44.4%) combined grade. Positive immunostainings were detected with androgen receptor (100%), PGP 9.5 (74%), ERG (40.7%), chromogranin A (29.6%), and synaptophysin (18.5%) antibodies. The Ki-67 index value > 5% was observed in 15% of the cases. L1CAM immunostaining was negative in all cases. Fisher exact test showed that successful local control of metastases was associated to mild inflammation, organ confined disease, Ki-67 index < 5%, and Gleason index 3 + 3. A castration resistant status was associated with severe inflammation, atrophy, a Gleason index higher than 3 + 3, Ki-67 index ≥ 5%, and positive PGP 9.5, chromogranin A, and synaptophysin immunostainings. In conclusion, oligometastatic prostate adenocarcinoma does not have a specific clinical-pathologic profile. However, some histologic and immunohistochemical parameters of routine use may help with making therapeutic decisions.

Molecular Mechanisms Related with Oligometastatic Prostate Cancer—Is It Just a Matter of Numbers?

“…Moreover, a recent prospectively-conducted trial aimed to describe the pathologic characteristics (KI-67 index ≥ 5%, positive PGP 9.5, chromogranin A and synaptophysin) of patients with omPCa initially treated with radical prostatectomy. The authors concluded that oligometastatic prostate adenocarcinoma does not have a specific clinical-pathologic profile [18]. Some studies also suggest that oligometastatic progression can be regulated by epigenetic alterations.…”

Insights into Urological Cancer

“…In between these two extreme clinical settings, the third subset of patients is characterized by the development of only a few metastases (<5) along the clinical course of the disease, the so-called oligometastatic prostate adenocarcinoma. Oligometastatic prostate cancers are usually under-diagnosed because they do not present any specific clinical or histologic feature [ 30 ]. As a result, the on-time identification and application of any eventual treatment exclusively directed to the metastases remain a difficult challenge.…”