Department of Gynaecologic Endocrinology & Reproductive Medicine, Womens Hospital, University Hospital Heidelberg, Heidelberg, Germany
*E-mail: michael.bohlmann@med.uni-heidelberg.de
We read with interest the article by Blumenfeld et al. concerning the gonadotropin-releasing hormone agonistic analogue (GnRH-a) co-treatment in women of reproductive age receiving gonadotoxic chemotherapy for diseases such as leukaemia, lymphoma and systemic lupus erythematosus, or other autoimmune diseases [1]. Blumenfeld et al. should be congratulated for their skilful presentation of todays alternatives for fertility preservation, particularly, showing a significantly lower rate (3/58) of premature ovarian failure in patients with the combined GnRH-a and chemotherapy compared with those who were similarly treated with chemotherapy, but without GnRH-a adjuvant (32/58).
However, a few questions have to be put forward. First, neither the exact time of follow-up nor the patients outcome is mentioned for either group. As the "dosages of the various cytotoxic drugs were not significantly different between both groups", it would be of interest to know whether there was any difference with regard to the patients disease-free survival, especially since "several" (how many? when ?) patients in the control group suffered from recurrence of the disease. Were those with recurrent disease undergoing high-dose chemotherapy and autologous bone marrow transplantation not co-treated with GnRH-a?
Furthermore, Blumenfeld et al. focused primarily on the effect of the GnRH analogues on the ovaries. However, it is well established that tumour cell lines, both gynaecological [2] and non-gynaecological (e.g. pancreatic cancer cells [3]), may carry receptors for GnRH. Results from in vitro experiments suggest that GnRH analogues may modulate cancer cell growth [2], possibly by interfering with the stimulatory effect of growth factors (such as epidermal growth factor [4]) and enhance the cytotoxic effects of chemotherapy [5]. It would therefore be of interest whether such results, with hypothetical beneficial effects, might also be obtained from experiments with lymphoma or leukaemia cells. However, to our knowledge, no experimental data are available on the interaction of GnRH-a and lymphoma or leukaemia cells. In our opinion, such hypothetical effects should therefore be studied in detail before considering a combined GnRH-a and chemotherapy regimen for diseases such as leukaemia, lymphoma and systemic lupus erythematosus "in every woman of reproductive age".
In addition, the patients age range in the Abstract (1540 years) and in Table 1 (1440 years) do not match.
Acknowledgements
Michael K. Bohlmann was supported by a grant from the Medical Faculty, University of Heidelberg, Germany.
M. K. Bohlmann*, M. von Wolff & T. Strowitzki
Department of Gynaecologic Endocrinology & Reproductive Medicine, Womens Hospital, University Hospital Heidelberg, Heidelberg, Germany (*E-mail: michael.bohlmann{at}med.uni-heidelberg.de)
References
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