Summary

This review gathered 39 studies on breast removal surgery for young people with gender distress and rated how trustworthy the evidence was. Nearly all only followed operated patients, with no comparison group. Only short-term surgical complications were rated high-quality evidence, and they were uncommon: no deaths, about 2% to 3% loss of the nipple or skin graft through tissue death, and about 5% thick scarring. For the results that matter most, such as gender distress, mental health, suicide attempts, quality of life and regret, the evidence was weak or very weak. One study did suggest people were about half as likely to self-harm after surgery. The authors call for better studies. The review shows the evidence is weak; it does not show that surgery fails to help. It was funded by SEGM, a group that urges caution, and surgeons have challenged its framing in published letters.

Key findings

• این مرور 39 مطالعه یافت که تا ژوئن 2023 جست‌وجو شده بود: فقط 3 مطالعه گروه‌ها را مقایسه کردند و 2 مطالعه افراد را پیش و پس از جراحی سنجیدند؛ 34 مطالعهٔ دیگر فقط بیماران جراحی‌شده را توصیف کردند.
• شواهد باکیفیت بالا فقط از مطالعات عوارض جراحی آمد: بدون مرگ (5 مطالعه)، حدود 20 نفر از 1,000 نفر نوک پستان یا پیوند پوست را به‌دلیل مرگ بافت از دست دادند (13 مطالعه)، حدود 10 نفر از 1,000 نفر یک فلپ پوست را از دست دادند (3 مطالعه) و حدود 50 نفر از 1,000 نفر جای زخم ضخیم داشتند (12 مطالعه).
• دو مطالعه که جراحی را با بستن سینه مقایسه کردند شواهد بسیار ضعیفی دربارهٔ ناراحتی جنسیتی مرتبط با سینه و رضایت از بدن و سینه دادند.
• یک مطالعه که جراحی را با نبود جراحی مقایسه کرد شواهد بسیار ضعیفی دربارهٔ ناراحتی و اقدام به خودکشی داد، و شواهد ضعیفی که افراد پس از جراحی حدود نصف احتمال آسیب به خود (بدون قصد خودکشی) را داشتند.
• کیفیت زندگی، افسردگی، مرگ با خودکشی، رضایت از سینه و پشیمانی همگی شواهد بسیار ضعیف ارزیابی شدند، عمدتاً چون گروه مقایسه وجود نداشت.
• بررسی‌های برنامه‌ریزی‌شده برای اینکه آیا نتایج بر حسب شرایط سلامت روان دیگر، سن شروع ناراحتی یا گرایش جنسی فرق می‌کند انجام نشد، و افکار خودکشی، عملکرد جنسی و جراحی‌های بعدی ارزیابی نشد.
• نویسندگان خواستار مطالعاتی با پیگیری رو به جلو و، اگر اخلاقی باشد، کارآزمایی‌های تصادفی هستند تا به بیماران، جراحان، نویسندگان رهنمود و سیاست‌گذاران اطلاع دهند.

Abstract

BACKGROUND: Gender dysphoria (GD) refers to psychological distress associated with the incongruence between one's sex and one's gender. In response to GD, birth-registered female patients may choose to undergo mastectomy. In this systematic review, the authors summarize and assess the certainty of the evidence about the effects of mastectomy. METHODS: We searched MEDLINE, Embase, PsycINFO, Social Sciences Abstracts, LGBTQ+ Source, and Sociological Abstracts through June 20, 2023. We included studies comparing mastectomy to no mastectomy in birth-registered patients younger than 26 years with GD. Outcomes of interest included psychological and psychiatric outcomes, and physical complications. Pairs of reviewers independently screened articles, abstracted data, and assessed risk of bias of the included studies. We performed meta-analysis and assessed the certainty of the evidence using the Grading of Recommendations Assessment, Development, and Evaluation approach. RESULTS: We included 39 studies. Observational studies (n = 2) comparing mastectomy to chest binding provided very low-certainty evidence for the outcome of GD. One observational study comparing mastectomy to no mastectomy provided very low-certainty evidence for the outcomes of global functioning and suicide attempts, and low-certainty evidence for the outcome nonsuicidal self-injury (adjusted OR, 0.47; 95% CI, 0.22 to 0.97). Before-and-after (n = 2) studies provided very low-certainty evidence for all outcomes. Evidence from case series (n = 34) studies ranged from high to very low certainty. CONCLUSIONS: Case series studies demonstrated high-certainty evidence for the outcomes of death, necrosis, and excessive scarring; however, these are limited in methodologic quality. In comparative and before-and-after studies, the evidence ranged from low to very low certainty.

Conclusion

The best available evidence reporting the effects of mastectomy in individuals with GD ranged from high to very low certainty. High certainty evidence in this SR was derived from case series studies only. High-certainty evidence from prospective cohort studies and, if ethical, randomized controlled trials, are needed to describe the short- and long-term effects of mastectomy in individuals with GD on mental health outcomes. Higher certainty evidence would be useful to individuals with GD considering chest masculinization; clinicians and surgeons involved in their care; guideline developers; and policy makers and stakeholders who make decisions about treatment related to GD.