Icsm Consider Tt After Radiation Good Response

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name: icsm-consider-tt-after-radiation-good-response
description: This skill guides clinicians to consider testosterone therapy after definitive radiation or brachytherapy for prostate cancer when the patient shows a good post-treatment response (e.g., stable low PSA) and remains low-risk. It is triggered when a patient with persistent hypogonadism symptoms and low testosterone levels is being followed post-radiotherapy and the clinician questions the safety of initiating testosterone therapy.
---

# Consider testosterone therapy after radiation or brachytherapy with good post-treatment response and low risk

## STEP 1 — Gather Information
Collect post-treatment PSA (preferably nadir <0.2 ng/dL), cancer risk stratification (e.g., NCCN or D'Amico), symptoms of hypogonadism (low libido, fatigue, ED), morning total testosterone on two occasions (<12 nmol/L), digital rectal exam, and ensure no evidence of biochemical recurrence or metastatic disease.

## STEP 2 — Rule In / Rule Out
Is there any evidence of biochemical recurrence, rising PSA, or active prostate cancer? If yes, rule out testosterone therapy; if no, proceed.

## STEP 3 — Classify or Stratify
Classify the patient as low-risk (per NCCN/D'Amico) with good post-treatment response (stable PSA nadir). If intermediate/high-risk or poor response, testosterone therapy is generally not recommended.

## STEP 4 — Decide
For low-risk patients with good response and confirmed hypogonadism, discuss risks/benefits and consider offering testosterone therapy after shared decision-making, with baseline PSA/DRE and plan for monitoring per Table4.

## Clinical Guardrails / Mimics / Pitfalls
Do not initiate testosterone therapy if PSA is rising, if high/intermediate-risk disease persists, if metastatic disease is present, or if the patient has a history of thromboembolic events without hematocrit evaluation. Avoid using testosterone monotherapy for erectile dysfunction without confirmed hypogonadism.

## Concrete Clinical Example
A 68-year-old man treated with external beam radiation for Gleason 3+4 prostate cancer has a PSA nadir of 0.1 ng/dL at 12 months, NCCN low-risk, reports fatigue and low libido, and has two morning total testosterone measurements of 8 nmol/L. No evidence of recurrence. After discussing risks/benefits, testosterone therapy is considered.

**Source:** Male hypogonadism: recommendations from the Fifth International Consultation on Sexual Medicine (ICSM 2024), International Society for Sexual Medicine, 2025, https://doi.org/10.1093/sxmrev/qeaf036