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
- Apžvalgoje rasta 39 tyrimai, ieškota iki 2023 m. birželio: tik 3 lygino grupes ir 2 matavo žmones prieš ir po operacijos; kiti 34 tik aprašė operuotus pacientus.
- Aukštos kokybės įrodymai gauti tik iš chirurginių komplikacijų tyrimų: mirčių nebuvo (5 tyrimai), apie 20 iš 1 000 prarado spenelį ar odos transplantatą dėl audinių žūties (13 tyrimų), apie 10 iš 1 000 prarado odos atplaišą (3 tyrimai), o apie 50 iš 1 000 susidarė stori randai (12 tyrimų).
- Du tyrimai, lyginantys operaciją su krūtinės suveržimu, davė labai silpnų įrodymų apie su krūtine susijusį genderinį distresą ir pasitenkinimą kūnu bei krūtine.
- Vienas tyrimas, lyginantis operaciją su jos nebuvimu, davė labai silpnų įrodymų apie distresą ir bandymus nusižudyti bei silpnų įrodymų, kad po operacijos žmonės maždaug perpus rečiau žalojosi (be minčių apie savižudybę).
- Gyvenimo kokybė, depresija, mirtis nuo savižudybės, pasitenkinimas krūtine ir gailestis visi buvo įvertinti kaip labai silpni įrodymai, daugiausia dėl palyginamosios grupės nebuvimo.
- Planuotų patikrinimų, ar rezultatai skyrėsi pagal kitas psichikos sveikatos būkles, distreso pradžios amžių ar seksualinę orientaciją, atlikti nepavyko, o savižudiškos mintys, lytinė funkcija ir vėlesnės operacijos nebuvo vertinamos.
- Autoriai ragina atlikti tyrimus, kurie stebėtų pacientus laikui bėgant, o jei tai etiška – ir atsitiktinių imčių tyrimus, kad informacija pasitarnautų pacientams, chirurgams, gairių rengėjams ir politikos formuotojams.
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.