detrans.ai 

Back to studies

荷蘭世代研究發現：使用荷爾蒙的跨性別女性乳癌風險是男性的46倍——但仍低於女性

接受荷爾蒙治療的跨性別者的乳癌風險：荷蘭全國世代研究

世代與登記研究跨性激素治療
Authors
Christel J.M. de Blok, Chantal M. Wiepjes, Nienke M. Nota, Klaartje van Engelen, Muriel A. Adank, Koen M.A. Dreijerink, Ellis Barbé, Inge R.H.M. Konings, Martin den Heijer
Journal
BMJ
Year
2019
Source
https://doi.org/10.1136/bmj.l1652

Summary

Researchers used records from the Amsterdam gender clinic, which treats over 95% of Dutch transgender patients, linked to the national record of cancer diagnoses. They counted breast cancers in about 3,500 people on cross-sex hormones. Trans women got breast cancer far more often than men normally do (about 46 times), but still less often than women. Their tumours looked like the typical hormone-sensitive breast cancers seen in women. This suggests estrogen, and possibly the testosterone-blocking drug cyproterone acetate, shifts risk toward the female pattern. Trans men had a lower risk than women, likely helped by having had their breasts removed. The authors concluded the overall risk is low and normal screening is enough. With only 15 and 4 cases, missing data on major risk factors, and comparisons with the general population, the numbers are rough.

Key findings

  • 研究追蹤了 2,260 名跨性別女性和 1,229 名跨性別男性接受荷爾蒙治療，總計約 34,000 和 15,000 人年的追蹤。
  • 跨性別女性在使用荷爾蒙典型的 18 年後（範圍 7 到 37 年）出現 15 例乳癌，典型年齡為 50 歲。
  • 乳癌在跨性別女性中約為男性的 46 倍（可能介於 27 到 75 倍），但只有女性的約三分之一。
  • 跨性別女性的腫瘤多為荷爾蒙敏感型（83% 受雌激素餵養、67% 受黃體素餵養），與女性通常所見的相同。
  • 跨性別男性有 4 例乳癌，約為女性比率的五分之一，但為男性比率的 59 倍；三例發生在乳房切除多年之後。
  • 研究者無法比較不同的荷爾蒙藥物，因為治療經常改變，而且多數跨性別女性服用的是 cyproterone acetate。
  • 作者的結論是，正常的乳房篩檢規則對使用荷爾蒙的跨性別者已經足夠。

Abstract

OBJECTIVE: To investigate the incidence and characteristics of breast cancer in transgender people in the Netherlands compared with the general Dutch population. DESIGN: Retrospective, nationwide cohort study. SETTING: Specialised tertiary gender clinic in Amsterdam, the Netherlands. PARTICIPANTS: 2260 adult trans women (male sex assigned at birth, female gender identity) and 1229 adult trans men (female sex assigned at birth, male gender identity) who received gender affirming hormone treatment. MAIN OUTCOME MEASURES: Incidence and characteristics (eg, histology, hormone receptor status) of breast cancer in transgender people. RESULTS: The total person time in this cohort was 33 991 years for trans women and 14 883 years for trans men. In the 2260 trans women in the cohort, 15 cases of invasive breast cancer were identified (median duration of hormone treatment 18 years, range 7-37 years). This was 46-fold higher than in cisgender men (standardised incidence ratio 46.7, 95% confidence interval 27.2 to 75.4) but lower than in cisgender women (0.3, 0.2 to 0.4). Most tumours were of ductal origin and oestrogen and progesterone receptor positive, and 8.3% were human epidermal growth factor 2 (HER2) positive. In 1229 trans men, four cases of invasive breast cancer were identified (median duration of hormone treatment 15 years, range 2-17 years). This was lower than expected compared with cisgender women (standardised incidence ratio 0.2, 95% confidence interval 0.1 to 0.5). CONCLUSIONS: This study showed an increased risk of breast cancer in trans women compared with cisgender men, and a lower risk in trans men compared with cisgender women. In trans women, the risk of breast cancer increased during a relatively short duration of hormone treatment and the characteristics of the breast cancer resembled a more female pattern. These results suggest that breast cancer screening guidelines for cisgender people are sufficient for transgender people using hormone treatment.

Conclusion

This large nationwide cohort study in the Netherlands showed an increased risk of breast cancer in trans women compared with cisgender men. The risk in trans women is still lower than in Dutch cisgender women and resembles a more female type of breast cancer and hormone receptor status. In trans men, a lower risk compared with Dutch cisgender women was observed. Based on this study, we conclude that the absolute overall risk of breast cancer in transgender people remains low and therefore it seems sufficient for transgender people using hormone treatment to follow screening guidelines as for cisgender people. As the risk of breast cancer in trans women increased during a relatively short duration of hormone treatment, it would be worthwhile for future studies to investigate in more detail the cause of breast cancer in transgender people receiving hormone treatment.