Case Overview: A 67-Year-Old Man With Metastatic CSPC

Charles Ryan, MD: Today we’re going to talk about a case in prostate cancer that illustrates a lot of the current thinking in how to manage this disease as it evolves over time.

This is a 67-year-old man with metastatic castration-sensitive prostate cancer. Here we have a 67-year active man presenting with intermittent back pain and loss of appetite, who has an unremarkable past medical history, and a family history of cardiac disease with his father having a myocardial infarction and a history of dementia but no history of prostate cancer or any other cancers in the family.

He presents to a physician and is found to have, on digital rectal exam, an asymmetric enlarged prostate, but he is otherwise unremarkable on clinical exam. He undergoes a prostate biopsy with transrectal ultrasound, which reveals him to have a T2 prostate adenocarcinoma, grade group 3. And a bone scan done to work this up reveals 3 spinal lesions at T10, L2, L3, and 1 in the left iliac crest. An abdominal pelvic CT [computed tomography] scan showed no other sign of metastatic disease. And PSA [prostate-specific antigen], unsurprisingly, is elevated at 24.9 ng/mL.

Then he is presented and counseled on various treatment options for his disease, which would be considered metastatic. There are a lot of options to consider in a patient like this.

One of the issues in the current era, in 2020, 2021, of course is, do we do anything besides standard hormonal therapy? And it’s quite interesting that for many decades, standard hormonal therapy was the first choice of treatment. I would say that treatment was done in an expectant fashion, where we would start with standard hormonal therapy. When the disease got worse, then we would bring in further therapy. But there are a lot of studies that we can discuss now that allow us to bring in additional therapies earlier in the clinical course that lead to enhanced clinical benefit.

He most likely was counseled around the use of an AR [androgen receptor]–targeted drug such as abiraterone or enzalutamide, both of which have significant level 1 evidence favoring their use in the castration-sensitive metastatic prostate cancer patient; as does docetaxel, which is approved for use in the castration-sensitive metastatic setting, based essentially on the CHAARTED study done in the United States and the STAMPEDE study done in the United Kingdom.

The patient starts docetaxel, plus ADT [androgen deprivation therapy]. This is initiated at 6 cycles, which he tolerates well and his PSA declines to 6.2 ng/mL.

Now just a brief point about what I counsel patients. For most of my patients with high-volume disease such as this, with a high PSA such as this, and especially in a healthy patient who’s relatively young such as this, I do recommend chemotherapy, although I do pick it as not the only choice.

The advantage of chemotherapy in this setting is that it’s a prime period of treatment. It’s actually just 6 cycles of docetaxel, 6 doses of a drug, 6 visits to the clinic, and then that treatment is done. That compares very favorably from a survival perspective, for example, with the use of abiraterone or enzalutamide in this setting as well.

So patients really have a choice. If they want to avoid chemotherapy altogether, they can take enzalutamide or abiraterone, but they are required in that case to take many pills per day. There is ongoing monitoring that is required, and the treatment is somewhat open ended. It’s not done after a period of 16 to 18 weeks, as docetaxel is.

Oftentimes, given those choices, patients will decide, “I’ll take the chemotherapy,” because if you look forward 16 weeks from now, they will be done with all that treatment, and some people find that favorable.

Of course there are some potential risks from the chemotherapy, such as marrow suppression, that one needs to take carefully into consideration. In particular, in your older patients, or patients with prior radiation therapy, or patients with prior chemotherapy exposure, or other factors that might make chemotherapy a little more caution inducing than an oral therapy.

Transcript edited for clarity.

Case: A 67-Year-Old Male with Metastatic Castrate-Sensitive Prostate Cancer

Initial presentation

• A 67-year-old active man presented with intermittent back pain and loss of appetite
• PMH: unremarkable
• FH: the patient’s father suffered a myocardial infarction at age 69; paternal grandmother had dementia; no known family history of cancer
• PE: DRE revealed asymmetric enlarged prostate; PE otherwise unremarkable
  
  

Clinical workup

• Core needle biopsy with TRUS showed adenocarcinoma of prostate
  • Stage T2N0M1b
  • Grade group 3
• Bone scan reveal 3 spinal lesions (T10, L2, L3) and 1 near the left iliac crest
• Abdominal and pelvic CT scan showed no other organ metastases
• PSA 24.9 ng/mL
  
  

Treatment and Follow-Up

• The patient was counselled on treatment options; he expressed concern regarding long-term AR exposure
• DOCE + ADT was initiated, 6 cycles were well-tolerated; PSA 6.2 ng/mL
• 2-year follow-up PSA 10.8 ng/mL; continued treatment regimen
  • 5 months later he reported increasing back pain and difficulty walking
  • PSA 21.4 ng/mL
  • PSADT 5.1 months
  • No new bone lesions on imaging
• Abiraterone 1000 mg PO qDay + prednisone 5 mg PO q12hr was initiated
• 1 year later PSA 30.2 ng/mL
  • Abdominal/pelvic CT showed multiple new small liver lesions, 1 new vertebral lesion and 1 new appendicular lesion
• Treatment with cabazitaxel 20 mg/m2 IV q3W + prednisone 10 mg PO qDay was initiated