Myotonic dystrophy: reproductive cancer risk factors in women

Takeaway

• This study found no significant reproductive cancer factor differences between female myotonic dystrophy type 1 (DM1) and type 2 (DM2) individuals, except for a possibility of a higher frequency of hysterectomy and hormone therapy (HT) use in DM2 patients.

Why this matters

• Findings warrant larger studies to evaluate the possible link between reproductive cancer risk factors and the risk of tumors in women.

Study design

• This study included 286 women, clinically confirmed as having DM and self-enrolled in the UK DM Registry (n=124: DM1=120, DM2=4) and the US National Registry of DM (n=162: DM1=122, DM2=40
• Differences in reproductive cancer risk factors by DM subtype assessed using questionnaires.       
• Funding: Intramural Research Program of the Division of Cancer Epidemiology and Genetics, and others.

Key results

• DM2 patients were older than DM1 patients in both countries (mean age, US: 59.8 vs 51.2 years, P=.0001; UK: 52.2 vs 46.2 years, P=.37).
• No statistically significant differences were observed between DM1 and DM2 regarding menstrual history or fertility-related factors.
• Women with DM2 vs those with DM1 were more likely to have used menopausal HT (52.3% vs 22.1%; P<.0001) and had a hysterectomy (53.5% vs 29.5%; P<.01).
• The frequency of self-reported reproductive organ tumours was not significantly different comparing DM1 with DM2 (P=.28).
• Women with DM2 vs those with DM1 had a lower risk for malignant tumours (OR, 0.72; P=.69).

Limitations

• Self-reported data.
• Results may not be generalisable to the entire DM population.