Preservation of ovarian function by ovarian shielding when undergoing total body irradiation for hematopoietic stem cell transplantation: a report of two successful cases

Total Body Irradiation in Haematopoietic Stem Cell Transplantation for Paediatric Acute Lymphoblastic Leukaemia: Review of the Literature and Future Directions

Total body irradiation (TBI) has been a pivotal component of the conditioning regimen for allogeneic myeloablative haematopoietic stem cell transplantation (HSCT) in very-high-risk acute lymphoblastic leukaemia (ALL) for decades, especially in children and young adults. The myeloablative conditioning regimen has two aims: (1) to eradicate leukaemic cells, and (2) to prevent rejection of the graft through suppression of the recipient's immune system. Radiotherapy has the advantage of achieving an adequate dose effect in sanctuary sites and in areas with poor blood supply. However, radiotherapy is subject to radiobiological trade-offs between ALL cell destruction, immune and haematopoietic stem cell survival, and various adverse effects in normal tissue. To diminish toxicity, a shift from single-fraction to fractionated TBI has taken place. However, HSCT and TBI are still associated with multiple late sequelae, leaving room for improvement. This review discusses the past developments of TBI and considerations for dose, fractionation and dose-rate, as well as issues regarding TBI setup performance, limitations and possibilities for improvement. TBI is typically delivered using conventional irradiation techniques and centres have locally developed heterogeneous treatment methods and ways to achieve reduced doses in several organs. There are, however, limitations in options to shield organs at risk without compromising the anti-leukaemic and immunosuppressive effects of conventional TBI. Technological improvements in radiotherapy planning and delivery with highly conformal TBI or total marrow irradiation (TMI), and total marrow and lymphoid irradiation (TMLI) have opened the way to investigate the potential reduction of radiotherapy-related toxicities without jeopardising efficacy. The demonstration of the superiority of TBI compared with chemotherapy-only conditioning regimens for event-free and overall survival in the randomised For Omitting Radiation Under Majority age (FORUM) trial in children with high-risk ALL makes exploration of the optimal use of TBI delivery mandatory. Standardisation and comprehensive reporting of conventional TBI techniques as well as cooperation between radiotherapy centres may help to increase the ratio between treatment outcomes and toxicity, and future studies must determine potential added benefit of innovative conformal techniques to ultimately improve quality of life for paediatric ALL patients receiving TBI-conditioned HSCT.

Dosimetric evaluation of ovaries and pelvic bones associated with clinical outcomes in patients receiving total body irradiation with ovarian shielding

Total body irradiation (TBI) with ovarian shielding is expected to preserve fertility among hematopoietic stem cell transplant (HSCT) patients with myeloablative TBI-based regimens. However, the radiation dose to the ovaries that preserves ovarian function in TBI remains poorly understood. Furthermore, it is uncertain whether the dose to the shielded organs is associated with relapse risk. Here, we retrospectively evaluated the relationship between fertility and the dose to the ovaries, and between relapse risk and the dose to the pelvic bones. A total of 20 patients (median age, 23 years) with standard-risk hematologic diseases were included. Median follow-up duration was 31.9 months. The TBI prescribed dose was 12 Gy in six fractions for three days. Patients' ovaries were shielded with cylinder-type lead blocks. The dose-volume parameters (D98% and Dmean) in the ovaries and the pelvic bones were extracted from the dose-volume histogram (DVH). The mean ovary Dmean for all patients was 2.4 Gy, and 18 patients recovered menstruation (90%). The mean ovary Dmean for patients with menstrual recovery and without recovery were 2.4 Gy and 2.4 Gy, respectively, with no significant difference (P = 0.998). Hematological relapse was observed in five patients. The mean pelvis Dmean and pelvis D98% for relapse and non-relapse patients were 11.6 Gy and 11.7 Gy and 5.6 Gy and 5.3 Gy, respectively. Both parameters showed no significant difference (P = 0.827, 0.807). In conclusion, TBI with ovarian shielding reduced the radiation dose to the ovaries to 2.4 Gy, and preserved fertility without increasing the risk of relapse.

Allogeneic Hematopoietic Cell Transplantation for Adolescent and Young Adult Patients with Acute Myeloid Leukemia

Limited data exist regarding the outcomes of allogeneic hematopoietic cell transplantation (allo-HCT) among adolescent and young adult (AYA) patients with acute myeloid leukemia (AML). Here we analyzed the features and outcomes of AYA patients with AML who had achieved complete remission (CR) and those who had not (non-CR) at allo-HCT. We retrospectively analyzed 2350 AYA patients with AML who underwent allo-HCT with a myeloablative conditioning regimen and who were consecutively enrolled in the Japanese nationwide HCT registry. The difference in overall survival (OS) between younger (age 16 to 29 years) and older AYA (age 30 to 39 years) patients in CR at transplantation was not significant (70.2% versus 71.7% at 3 years; P = .62). Meanwhile, this difference trended toward a statistical significance between younger and older AYA patients in non-CR at transplantation (39.5% versus 34.3% at 3 years; P = .052). In AYA patients in CR and non-CR, the age at transplantation did not affect relapse or nonrelapse mortality (NRM). In AYA patients in CR, no difference in OS was observed between those who received total body irradiation (TBI) and those who did not (71.1% versus 70.5% at 3 years; P = .43). AYA patients who received TBI-based conditioning had a significantly lower relapse rate and higher NRM than those who underwent non-TBI-based conditioning (relapse: 19.8% versus 24.1% at 3 years [P = .047]; NRM: 14.7% versus 11.1% at 3 years [P = .021]). In contrast, among the non-CR patients, there were no differences between the TBI and non-TBI groups with respect to OS (P = .094), relapse (P = .83), and NRM (P = .27). Our data indicate that outcomes may be more favorable in younger AYA patients than in older AYA patients in non-CR at transplantation, and that outcomes of TBI-based conditioning could be comparable to those of non-TBI-based conditioning for AYA patients.

A Preliminary Report of Gonadal-Sparing TBI Using a VMAT Technique

Reproductive toxicity is common after total body irradiation (TBI) and has major quality of life implications for patients. In that context, this is the first report of gonadal-sparing volumetric-modulated arc therapy (VMAT) TBI, successfully delivered in a boy and a girl with aplastic anemia. Both patients' VMAT TBI plans demonstrated improved gonadal sparing versus simulated conventional 2-dimensional (2D) approach (mean testes dose, 0.45 Gy VMAT vs 0.72 Gy 2D; mean ovary dose, 0.64 Gy VMAT vs 1.47 Gy 2D). Planning target volume coverage was also improved for both cases with the VMAT plan versus conventional 2D plan (2 Gy D90% vs 1.9 Gy D90%, respectively). Given these dosimetric advantages, the present study can serve as a proof-of-concept for further prospective studies evaluating this technique for wider applications in populations receiving TBI.

Fertility and pregnancy in cancer survivors

Cancer survivors are increasing as improvements in cancer diagnosis and treatment translate to improved outcomes. As cancer survivors in their reproductive years contemplate pregnancy, it is important to understand the impact of cancer and its treatment on fertility and pregnancy outcomes. Cancer treatments such as chemotherapy and radiotherapy can affect patients' fertility, and strategies are available to help preserve the future fertility of survivors. The potential impact of previous cancer diagnoses and treatments on pregnancy and maternal and fetal outcomes needs to be assessed and discussed with survivors, with support from materno-fetal medicine specialists and high-risk antenatal services as needed.

Perspectives on the co-treatment with GnRHa in female patients undergoing hematopoietic stem cell transplantation

Outcomes after hematopoietic stem cell transplantation (HSCT) for patients with both malignant and nonmalignant diseases have improved significantly in recent years. However, the endocrine system is highly susceptible to damage by the high-dose chemotherapy and/or irradiation used in the conditioning regimen before HSCT. Ovarian failure and subsequent infertility are frequent complications that long-term HSCT survivors and their partners face with a negative impact on their QoL. Several meta-analyses of randomized clinical trials showed that gonadotropin-releasing hormone agonist (GnRHa) administration in advance of starting standard chemotherapy decreases the risk of gonadal dysfunction and infertility in cancer patients, but GnRHa use for ovarian protection in HSCT patients is not fully determined. In this review, we are discussing the potential preservation of ovarian function and fertility in pubertal girls/premenopausal women who undergo HSCT using GnRHa in parallel with conditioning chemotherapy, focusing on the current data available and making some special remarks regarding the use of GnRHa.

Fertility challenges for women with sickle cell disease

INTRODUCTION

Sickle cell disease (SCD) represents one of the most common monogenic blood disorders worldwide, with an incidence of over 300,000 newborns affected per year. Reproductive challenges for men and women with SCD have been previously reviewed; however, evidence-based strategies to prevent and manage infertility and increase fecundity are lacking in women with SCD, which is one of the most important factors for quality of life. Areas covered: This review article summarizes the known risk factors for infertility, low fecundity, and premature menopause related to SCD. Expert commentary: Women with SCD have unique risk factors that may impact their ability to conceive, including chronic inflammation, oxidative stress, transfusion-related hemochromatosis, and ovarian sickling, causing ischemia and reperfusion injury to the ovary. Contraception is strongly recommended while on hydroxyurea therapy during reproductive years and discontinuing hydroxyurea for family planning and during pregnancy based on teratogenicity in animal studies. Hematopoietic stem cell transplantation (HSCT), the only curative therapy, sometimes involves conditioning regimens containing alkylating agents and total body irradiation that contribute to infertility and premature ovarian failure. Prior to HSCT or gene therapy, we strongly recommend referral to a reproductive endocrinologist to discuss fertility preservation and surrogacy options for all women with SCD.

Ovarian function after hematopoietic cell transplantation: a descriptive study following the use of GnRH agonists for myeloablative conditioning and observation only for reduced-intensity conditioning

Gonadal failure is a health and quality-of-life concern in hematopoietic cell transplant (HCT) survivors. While ovarian dysfunction is nearly universal following myeloablative (MA) conditioning, the risk is unclear after reduced-intensity conditioning (RIC). Gonadotropin-releasing hormone agonists decrease ovarian failure rates following conventional chemotherapy, but little is known about its effectiveness with HCT. We investigated the impact of leuprolide on ovarian function after MA conditioning and monitored ovarian function after RIC in this descriptive pilot study. Post-menarchal females <50 years undergoing HCT with adequate baseline ovarian function (follicle-stimulating hormone (FSH) level <40 mIU/mL and normal menstruation) were eligible. Prior to MA conditioning, leuprolide was administered. Those undergoing RIC were observed. FSH was measured at various time points. Seventeen women aged 12-45 years were evaluated (7 in the intervention group and 10 in the observation group). Compared to the historical high rate of ovarian failure after MA conditioning, 3 of 7 evaluable Lupron recipients had ovarian failure at a median of 703 days post transplant. Ovarian failure occurred in 1 of 10 recipients of RIC at a median follow-up of 901 days. In conclusion, leuprolide may protect ovarian function after MA conditioning. Additionally, RIC with cyclophosphamide, fludarabine and low-dose TBI has a low risk of ovarian failure.

Successful Pregnancy and Delivery After Radiation With Ovarian Shielding for Acute Lymphocytic Leukemia Before Menarche

Total body irradiation is performed as a preconditioning regimen to inhibit graft-versus-host disease after bone marrow transplantation and to eradicate remaining tumor cells. However, these regimens result in delayed secondary sex characteristics and failure of ovarian function recovery, leading to amenorrhea and infertility. Herein, we report a case of an 11-year-old girl diagnosed with acute lymphocytic leukemia who received induction chemotherapy and prophylactic cranial irradiation. For bone marrow transplantation, she received total body irradiation of 12 Gy with uterine and ovarian shielding at 13 years of age. The patient remained in remission and menarche began at 14 years of age. At 23, she became pregnant and delivered a baby naturally with no abnormalities.

Ovarian function after allogeneic hematopoietic stem cell transplantation in childhood and adolescence

OBJECTIVE

The aim of the study was to evaluate long-term ovarian function after allogeneic hematopoietic stem cell transplantation (HSCT) in childhood and adolescence.

SUBJECTS AND METHODS

Predictive factors for ovarian function were evaluated among 92 adult or pubertal female survivors transplanted at Huddinge and Helsinki University Hospital during 1978-2000, at a mean age of 9±4.3 years (range 1-19). At the time of the study a mean±s.d. of 13±5.5 years (range 6-27) had elapsed since the HSCT and the mean age of the participants was 22±6.3 years (range 9-41).

RESULTS

Spontaneous puberty based on breast development occurred in 40 and menarche in 30 of the 70 girls who were prepubertal at transplantation. Six out of 20 girls who received HSCT after initiation of pubertal development recovered their ovarian function. Younger age at HSCT, conditioning without total body irradiation (TBI), and a non-leukemia diagnosis predicted the spontaneous menarche. The incidence of menarche was higher after fractioned vs single fraction TBI (P<0.05), cyclophosphamide (Cy) vs busulfan (Bu)-based conditioning (P<0.05), and among leukemia patients transplanted at first remission vs later remissions (P<0.01) and with no cranial irradiation (cranial radiotherapy, CRT) vs given CRT (14-24 Gy) (P<0.01). The majority of recipients conditioned with only Cy vs TBI (P<0.001) or vs Bu-based regimens (P<0.01) showed preserved ovarian function and required no estrogen replacement at their latest follow-up visit at a mean age of 23±6.3 years (range 15-41). Ten women became pregnant.

CONCLUSIONS

Patients conditioned with TBI or Bu-based regimes are at high risk of ovarian failure. Intensive anti-leukemia therapy before HSCT including CRT especially among relapsed patients may further decrease the possibility of spontaneous menarche.

Clinical guide to fertility preservation in hematopoietic cell transplant recipients

With broadening indications, more options for hematopoietic cell transplantation (HCT) and improvement in survival, the number of long-term HCT survivors is expected to increase steadily. Infertility is a frequent problem that long-term HCT survivors and their partners face and it can negatively impact on the quality of life. The most optimal time to address fertility issues is before the onset of therapy for the underlying disease; however, fertility preservation should also be addressed before HCT in all children and patients of reproductive age, with referral to a reproductive specialist for patients interested in fertility preservation. In vitro fertilization (IVF) and embryo cryopreservation, oocyte cryopreservation and ovarian tissue banking are acceptable methods for fertility preservation in adult women/pubertal females. Sperm banking is the preferred method for adult men/pubertal males. Frequent barriers to fertility preservation in HCT recipients may include the perception of lack of time to preserve fertility given an urgency to move ahead with transplant, lack of patient-physician discussion because of several factors (for example, time constraints, lack of knowledge), inadequate access to reproductive specialists, and costs and lack of insurance coverage for fertility preservation. There is a need to raise awareness in the medical community about fertility preservation in HCT recipients.

Maintaining the reproductive potential of cancer patients during cancer treatment

Cancer therapies are known to alter the reproductive potential in cancer patients. Due to improved survival rates in cancer patients of reproductive age, considerations of the long-term effects of cancer therapy have become more significant. Oncofertility is a new discipline in medicine that deals with maintaining the reproductive potential of cancer patients while they are receiving gonadotoxic cancer treatment. The purpose of this review is to explore how cancer treatment impairs reproductive functioning and present the current options for preservation of fertility in women. All patients with reproductive potential should be made aware of the possible treatment-related infertility and be offered appropriate fertility preservation options before cancer treatment is instituted. The hope is that, in the future, mechanism(s) can be developed to preserve immature germ cells in the ovary, so that they can be used for fertilization in vivo or in vitro.

Protection of ovarian function by two distinct methods of ovarian shielding for young female patients who receive total body irradiation

To prevent ovarian dysfunction due to total body irradiation, we started ovarian shielding at our center (Saitama Medical Center, Jichi Medical University (SMC-JMU)) with a long source axis distance, which is different from the original method used at the University of Tokyo Hospital (UTH). We retrospectively analyzed the outcome of eight patients with a median age of 20.5 years from SMC-JMU and compared the results with the published data for eight patients with a median age of 22 years from UTH. The recovery of ovarian function was observed in five and six patients, respectively. The cumulative incidence of ovarian recovery, while treating relapse and death without ovarian recovery as competing risks, was 68.8 % at 2 years after transplantation in the total population, and there was no statistically significant difference between the two institutions (p = 0.85). Age and the history of previous chemotherapy did not affect the incidence of ovarian recovery. Two patients from each center had a relapse of leukemia. Overall, among the 11 patients who have survived without relapse, only one has not achieved ovarian recovery. In conclusion, ovarian shielding with both methods strongly protected ovarian function. However, we should continue to monitor the relapse rate among patients who undergo this procedure.

Fludarabine, cyclophosphamide, anti-thymocyteglobulin, and low-dose total body irradiation conditioning enables 1-HLA-locus-mismatched hematopoietic stem cell transplantation for very severe aplastic anemia without affecting ovarian function

Allogeneic hematopoietic stem cell transplantation for severe aplastic anemia from an alternative donor is associated with higher risks of graft rejection and severe graft-versus-host disease. We developed a conditioning regimen consisting of rabbit anti-thymocyte globulin, fludarabine, cyclophosphamide, and low-dose total body irradiation. Two adult female patients with transfusion-dependent very severe aplastic anemia underwent 1-locus mismatched transplantation using this regimen. Both patients achieved stable engraftment and the clinical course thereafter was uneventful with persistently normal ovarian function. This novel conditioning regimen may be suitable for alternative donor transplantation for severe aplastic anemia, especially in young female patients.

Endocrine complications of hematopoietic stem cell transplantation

Advances in hematopoietic stem cell transplantation (HSCT) have resulted in broader indications for this therapeutic modality in both malignant diseases and nonmalignant conditions. This article focuses on the late endocrine abnormalities that are most commonly observed following successful HSCT, with a special emphasis on pediatric HSCT recipients, for whom long-term follow-up data are increasingly available.