Cancer Risk Analysis Comparison

Introduction

Cancer is the long-term risk with the least direct evidence. Only steroids have a clear human signal, for liver tumors; the rest is epidemiology or inference from mechanism. The long-term effects overview covers the other risks.

Current Evidence

Established Risks

Compound	Cancer Type	Risk Level	Evidence
Oral steroids	Hepatocellular carcinoma, adenoma	Elevated	Case reports
Androgens	Prostate	Debated	Conflicting data
GH/IGF-1	Prostate, breast, colorectal	Theoretical concern	Epidemiological
SARMs	Unknown	Insufficient data	No long-term data

NIH's LiverTox database links long-term androgenic steroid use with hepatocellular carcinoma and hepatic adenoma, mostly through case reports. Non-cancer liver harm is covered in our liver and kidney comparison.

LiverTox's 2025 SARM chapter documents severe jaundice cases, not tumors. That reflects short follow-up, not proven safety. In a 2024 Phase 2 trial, the SARM enobosarm even showed anti-tumor activity in estrogen receptor-positive breast cancer.

Mechanism Concerns

Mechanism	Compounds	Risk Type
Unclear mechanism	Some oral steroids	Liver
Hormonal promotion	All androgens	Hormone-sensitive
Growth factor elevation	GH, IGF-1 peptides	General
Receptor activation	SARMs	Unknown
Angiogenesis	BPC-157	Theoretical

GH and IGF-1 Considerations

The IGF-1 Question

Factor	Consideration	Perspective
Elevated IGF-1	Epidemiologically linked to cancer	Concern
Physiological vs. supraphysiological	Dose matters	Nuance
Duration of elevation	Longer = more concern	Temporal
Existing cancer	May promote growth	Contraindication

A 2004 Lancet meta-analysis pooled 21 studies. IGF-1 at the 75th percentile, compared with the 25th, went with higher odds of prostate cancer (odds ratio 1.49) and premenopausal breast cancer (1.65). The authors called these associations modest.

A UK cohort of 1,848 people given pituitary growth hormone in 1959-1985 had raised colorectal cancer and Hodgkin's disease deaths, on two cases each. MK-677 held IGF-1 at young-adult levels for 2 years in a 65-person randomized trial. As of October 2026, no GH secretagogue trial we found measured cancer outcomes.

Repair Peptides and Angiogenesis

In animal studies, BPC-157 promotes angiogenesis via VEGFR2 and nitric oxide. A 2025 review calls tumor promotion theoretical and cites cell work where BPC-157 inhibited VEGF signaling in melanoma cells. As of October 2026, FDA's compounding safety page cites nonclinical findings that LL-37 "can be protumorigenic in some tissues" and case reports of melanoma with melanotan II.

Comparative Risk Assessment

Compound Class	Overall Cancer Risk	Confidence
Oral steroids	Elevated (liver)	Moderate
Injectable steroids	Uncertain	Low
GH/peptides	Theoretical concern	Low
SARMs	Unknown	Very low
Healing peptides	Not established	Very low

What we still don't know

No study has followed users of any class long enough to compare cancer rates. The main unknowns are whether years of moderately raised IGF-1 matter in healthy adults, and whether pro-angiogenic peptides affect undiagnosed tumors. Heart risks are compared in the cardiovascular comparison.