What is the plan of care for a patient in their late 60s with hyperglycemia, impaired renal function, hypercalcemia, and an elevated PSA level?

Plan of Care for Patient with Elevated PSA and Metabolic Abnormalities

This patient requires urgent urological referral for prostate biopsy given the markedly elevated PSA of 21.6 ng/mL, which confers a greater than 67% likelihood of harboring prostate cancer. 1

Immediate Priorities

1. Prostate Cancer Evaluation (Most Urgent)

The PSA level of 21.6 ng/mL is significantly elevated and demands immediate diagnostic workup:

• Refer to urology for transrectal ultrasound-guided prostate biopsy with a minimum of 10-12 cores under antibiotic cover and local anesthesia 1
• At PSA levels exceeding 20 ng/mL, approximately 36% of men have metastases to pelvic lymph nodes, and only 50% have organ-confined disease 1
• Consider multiparametric MRI to guide biopsy and improve diagnostic yield 1
• Imaging for metastatic disease should be obtained before or concurrent with biopsy, including technetium bone scan and thoraco-abdominal CT scan or whole-body MRI 1

Important caveat: Before proceeding, rule out acute prostatitis as a cause of PSA elevation, as bacterial prostatitis can cause dramatic PSA increases (up to 75 ng/mL in some cases) 2. However, given the absence of fever or urinary symptoms mentioned, this is less likely but should be briefly assessed.

2. Renal Function Management

The patient has impaired renal function with metabolic acidosis:

• BUN/Creatinine ratio of 9 is actually low (normal is 10-20), suggesting intrinsic renal disease rather than prerenal azotemia 3
• CO2 of 17 mEq/L indicates metabolic acidosis (normal 23-29), consistent with chronic kidney disease 3
• Calculate estimated GFR (eGFR) using creatinine, age, sex, and race to stage the chronic kidney disease 3
• Renal function decline is common in elderly patients, with approximately 40% reduction by age 70 3

Clinical implications for cancer workup:

• If eGFR is between 30-60 mL/min/1.73 m², the patient has moderate CKD (Stage 3) 3
• This will affect chemotherapy dosing if cancer is confirmed and requires systemic therapy 3
• Optimize hydration status before any contrast imaging or nephrotoxic procedures 3

3. Calcium and Glucose Abnormalities

Calcium of 10.3 mg/dL (upper limit of normal ~10.2) warrants attention:

• Mild hypercalcemia can be associated with malignancy, including prostate cancer with bone metastases 3
• Recheck ionized calcium and consider PTH level if confirmed elevated
• Review medications that may affect calcium (thiazides, calcium supplements, vitamin D)

Glucose of 105 mg/dL suggests prediabetes or early diabetes:

• This is a fasting glucose in the prediabetic range (100-125 mg/dL)
• Check HbA1c to assess glycemic control over time 3
• Initiate lifestyle modifications including medical nutrition therapy 3
• Monitor for progression, as diabetes management will be important if cancer treatment is needed

Diagnostic Algorithm

Step 1: Urgent Urological Referral (Within 1-2 Weeks)

• Do not delay for PSA confirmation given the markedly elevated level 1
• Perform digital rectal examination as part of complete evaluation 1
• Obtain baseline imaging for staging 1

Step 2: Concurrent Medical Optimization

• Calculate eGFR and stage CKD 3
• Assess and optimize volume status before procedures 3
• Recheck calcium (ionized) and investigate if persistently elevated
• Obtain HbA1c for diabetes screening 3

Step 3: Risk Stratification After Biopsy

If prostate cancer is confirmed:

• Treatment options depend on Gleason score, staging, and overall health status 1
• Even at age 67-69, if in good health with minimal comorbidities, the patient may be a candidate for definitive treatment with curative intent 1
• For high-risk disease (likely given PSA >20), options include radical prostatectomy, radiation therapy with androgen deprivation therapy, or androgen deprivation alone depending on disease extent 1

Critical Pitfalls to Avoid

• Do not adopt a "watchful waiting" approach without tissue diagnosis at this PSA level - the risk of clinically significant cancer is very high 1
• Do not assume age alone precludes treatment - individualized assessment of health status and life expectancy is necessary 1
• Do not administer IV contrast for imaging without assessing renal function and hydration status 3
• Do not initiate testosterone therapy (if being considered for any reason) until prostate cancer has been ruled out 3
• Do not delay urological referral to "optimize" other medical conditions first - the cancer evaluation is time-sensitive 1

Follow-up Monitoring

After initial workup:

• Nephrology referral if eGFR <45 mL/min/1.73 m² or rapidly declining 3
• Endocrinology referral if HbA1c confirms diabetes requiring complex management 3
• Close coordination between urology, nephrology, and primary care for treatment planning given renal impairment 3