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

Genital chronic graft-versus-host disease: an unmet need that requires trained gynecologists

OBJECTIVE

Menopause and chronic graft-versus-host disease (cGvHD) are the leading causes of morbidity after allogeneic hematopoietic stem cell transplantation (alloHSCT). Genitalia are one of the target organs of cGvHD causing sexual dysfunction and local symptoms, which may impair women's quality of life. The aim of this study is to describe the prevalence and clinical characteristics of genital cGvHD.

METHODS

A retrospective cross-sectional observational study was performed including 85 women with alloHSCT. All women were diagnosed and counseled by a trained gynecologist. Health-related quality of life was assessed by the Cervantes Short-Form Scale and sexual function was evaluated by the Female Sexual Function Index.

RESULTS

Seventeen women (20%) included in the study were diagnosed with genital cGvHD. The main complaints were vulvovaginal dryness (42.2%) and dyspareunia (29.4%), the presence of erythema/erythematous plaques (52.9%) being the most frequent sign. Median time from transplant to diagnosis of genital cGvHD was 17 months among those with mild involvement, 25 months for moderate and 42 months for severe forms. Mortality was 29.4% in patients who developed cGvHD with genital involvement versus 8.8% among those without (p = 0.012).

CONCLUSION

Early gynecological evaluation might allow to identify patients with mild forms of genital cGvHD, potentially enabling better management and improved outcomes.

Fertility Potential and Gonadal Function in Survivors of Reduced-Intensity Hematopoietic Stem Cell Transplantation

The use of reduced-intensity conditioning (RIC) regimens has increased in an effort to minimize hematopoietic stem cell transplantation (HCT) end-organ toxicity, including gonadal toxicity. We aimed to describe the incidence of fertility potential and gonadal function impairment in adolescent and young adult survivors of HCT and to identify risk factors (including conditioning intensity) for impairment. We performed a multi-institutional, international retrospective cohort study of patients age 10 to 40 years who underwent first allogeneic HCT before December 1, 2019, and who were alive, in remission, and available for follow-up at 1 to 2 years post-HCT. For females, an AMH level of ≥.5 ng/mL defined preserved fertility potential; an AMH level of ≥.03 ng/mL was considered detectable. Gonadal failure was defined for females as an elevated follicle-stimulating hormone (FSH) level >30 mIU/mL with an estradiol (E2) level <17 pg/mL or current use of hormone replacement therapy (regardless of specific indication or intent). For males, gonadal failure was defined as an FSH level >10.4 mIU/mL or current use of hormone replacement therapy. A total of 326 patients (147 females) were available for analysis from 17 programs (13 pediatric, 4 adult). At 1 to 2 years post-HCT, 114 females (77.6%) had available FSH and E2 levels and 71 (48.3%) had available AMH levels. FSH levels were reported for 125 males (69.8%). Nearly all female HCT recipients had very low levels of AMH. One of 45 (2.2%) recipients of myeloablative conditioning (MAC) and four of 26 (15.4%) recipients of reduced-intensity conditioning (RIC) (P = .06) had an AMH ≥.5 ng/m, and 8 of 45 MAC recipients (17.8%) and 12 of 26 RIC recipients (46.2%) (P = .015) had a detectable AMH level. Total body irradiation (TBI) dose and cyclophosphamide equivalent dose (CED) were not associated with detectable AMH. The incidence of female gonadal hormone failure was 55.3%. In univariate analysis, older age at HCT was associated with greater likelihood of gonadal failure (median age, 17.6 versus 13.9; P < .0001), whereas conditioning intensity (RIC versus MAC), TBI, chronic graft-versus-host disease requiring systemic therapy, and CED were not significantly associated with gonadal function. In multivariable analysis, age remained statistically significant (odds ratio [OR]. 1.11; 95% confidence interval [CI], 1.03 to 1.22) for each year increase; P = .012), Forty-four percent of the males had gonadal failure. In univariate analysis, older age (median, 16.2 years versus 14.4 years; P = .0005) and TBI dose (P = .002) were both associated with gonadal failure, whereas conditioning intensity (RIC versus MAC; P = .06) and CED (P = .07) were not statistically significant. In multivariable analysis, age (OR, 1.16; 95% CI, 1.06-1.27 for each year increase; P = .0016) and TBI ≥600 cGy (OR, 6.23; 95% CI, 2.21 to 19.15; P = .0008) remained significantly associated with gonadal failure. Our data indicate that RIC does not significantly mitigate the risk for gonadal failure in females or males. Age at HCT and (specifically in males) TBI use seem to be independent predictors of post-transplantation gonadal function and fertility status. All patients should receive pre-HCT infertility counseling and be offered appropriate fertility preservation options and be screened post-HCT for gonadal failure.

Leuprolide Protects Ovarian Reserve in Adolescents Undergoing Gonadotoxic Therapy

Purpose: Treatment sequelae compromising reproductive health are highly prevalent in childhood cancer survivors, and a main determinant of health and quality of life. Follicular reserve determines ovarian function life span; thus, its preservation is important in the care of female survivors. Anti-Müllerian hormone (AMH) is a biomarker to measure functional ovarian reserve. We aimed to evaluate the effect of leuprolide during gonadotoxic therapy on pubertal females' post-treatment functional ovarian reserve using AMH levels. Methods: We conducted a single-center retrospective study including all pubertal females who had undergone gonadotoxic treatments between January 2010 and April 2020, and had an AMH level after completion of therapy. We used multivariable linear regressions to compare AMH-level beta coefficients in patients stratified by gonadotoxic risk, adjusting for leuprolide use. Results: Fifty-two females meeting study eligibility were included, of which 35 received leuprolide. The use of leuprolide was associated with higher post-treatment AMH levels in the lower gonadotoxic risk group (beta 2.74, 95% CI 0.97-4.51; p = 0.004). This association was lost in the higher gonadotoxic risk groups. Conclusions: Leuprolide may have a protective effect on the functional ovarian reserve. However, this is limited by increasing treatment gonadotoxicity. Larger, prospective studies are needed to elucidate the potential benefits of gonadotropin-releasing hormone agonist on preservation of ovarian reserve among children receiving gonadotoxic therapies, as cancer survivors.

Risk factors of menopause after allogeneic hematopoietic cell transplantation in premenopausal adult women

OBJECTIVES

Allogeneic hematopoietic stem-cell transplantation (HCT) is the only curative option for most hematologic malignancies. However, HSCT can cause early menopause and various complications in premenopausal women. Therefore, we aimed to investigate risk factors predicting early menopause and its clinical implications among survivors post HCT.

METHODS

We retrospectively analyzed 30 adult women who had received HCT at premenopausal status between 2015 and 2018. We excluded patients who had received autologous stem cell transplantation, had relapsed, or died of any cause within 2 years of HCT.

RESULTS

The median age at HCT was 41.6 years (range, 22-53). Post-HCT menopause was identified in 90% of myeloablative conditioning (MAC) HCT and 55% of reduced-intensity conditioning (RIC) HCT (p = .101). In the multivariate analysis, the post-HCT menopausal risk was 21 times higher in a MAC regimen containing 4 days of busulfan (p = .016) and 9.3 times higher in RIC regimens containing 2-3 days of busulfan (p = .033) than that of non-busulfan-based conditioning regimens.

CONCLUSIONS

Higher busulfan dose in conditioning regimens is the most significant risk factor affecting post-HCT early menopause. Considering our data, we need to decide on conditioning regimens and individualized fertility counseling before HCT for premenopausal women.

Gonadotropin-releasing hormone agonist for the preservation of ovarian function in survivors of haematopoietic stem cell transplantation for haematological diseases

Objective

Administration of GnRH agonist (GnRHa) prior to chemotherapy may decreases the risk of gonadal dysfunction in patients with tumors. However, relevant data in haematopoietic stem cell transplantation (HSCT) recipients has not yet been established. Hence, the present study was designed to evaluate the clinical efficacy of GnRHa cotreatment prior to myeloablative regimens on ovarian protection in female survivors of HSCT for haematological diseases.

Patients and methods

Eligible patients were divided into a GnRHa group and a control group. Medical records regarding age at HSCT; diagnosis/indication for HSCT; pre- and posttransplantation serum sex hormone levels; menstruation and perimenopausal symptoms after HSCT were collected and compared. The primary and secondary outcome was the incidence of premature ovarian insufficiency (POI) symptoms associated with hypoestrogenism.

Results

A total of 330 patients were enrolled in the study: 19 patients were lost to follow-up, and clinical information was obtained in 311 patients. There was no significant difference in the primary outcome of follow-up between the two groups (78.50% [84 of 107] for the GnRHa group versus 83.33% [170 of 204] for the control group). The adjusted relative risks (RR) and 95% confidence interval (CI) were 1.19 and 0.73–1.93 (P = 0.487). Among patients who received cotreatment with GnRHa, 62.62% (67 of 107) complained of perimenopausal symptoms, which was significantly lower than the 74.51% (152 of 204) in the control group (adjusted RR: 1.46, 95% CI: 1.04–2.06, P = 0.031).

Conclusion

GnRHa cotreatment may not decrease the POI rate in HSCT survivors. However, it may reduce perimenopausal symptoms in this population, suggesting a potential benefit of GnRHa in clinical practice and warrant further researches.

The effect of hematopoietic stem cell transplantation on fertility and strategies for improvement

Ovarian dysfunction is an important consequence of hematopoietic stem cell transplantation (HCT). Premature ovarian failure and infertility can severely impact the quality of life for the increasing number of female long-term survivors of HCT. Here, we review the impact of HCT on ovarian function, post-transplant fertility and birth outcomes, and the contemporaneous strategies to preserve fertility for these patients.

GnRH Analogues as a Co-Treatment to Therapy in Women of Reproductive Age with Cancer and Fertility Preservation

In this review, we analyzed existing literature regarding the use of Gonadotropin-releasing Hormone (GnRH) analogues (agonists, antagonists) as a co-treatment to chemotherapy and radiotherapy. There is a growing interest in their application as a prophylaxis to gonadotoxicity caused by chemotherapy and/or radiotherapy due to their ovarian suppressive effects, making them a potential option to treat infertility caused by such chemotherapy and/or radiotherapy. They could be used in conjunction with other fertility preservation options to synergistically maximize their effects. GnRH analogues may be a valuable prophylactic agent against chemotherapeutic infertility by inhibiting rapid cellular turnover on growing follicles that contain types of cells unintentionally targeted during anti-cancer treatments. These could create a prepubertal-like effect in adult women, limiting the gonadotoxicity to the lower levels that young girls have. The use of GnRH agonists was found to be effective in hematological and breast cancer treatment whereas for ovarian endometrial and cervical cancers the evidence is still limited. Studies on GnRH antagonists, as well as the combination of both agonists and antagonists, were limited. GnRH antagonists have a similar protective effect to that of agonists as they preserve or at least alleviate the follicle degradation during chemo-radiation treatment. Their use may be preferred in cases where treatment is imminent (as their effects are almost immediate) and whenever the GnRH agonist-induced flare-up effect may be contra-indicated. The combination treatment of agonists and antagonists has primarily been studied in animal models so far, especially rats. Factors that may play a role in determining their efficacy as a chemoprotective agent that limits gonadal damage, include the type and stage of cancer, the use of alkylating agents, age of patient and prior ovarian reserve. The data for the use of GnRH antagonist alone or in combination with GnRH agonist is still very limited. Moreover, studies evaluating the impact of this treatment on the ovarian reserve as measured by Anti-Müllerian Hormone (AMH) levels are still sparse. Further studies with strict criteria regarding ovarian reserve and fertility outcomes are needed to confirm or reject their role as a gonadal protecting agent during chemo-radiation treatments.

Conditioning Intensity and Probability of Live Birth after Blood or Marrow Transplantation (BMT): a BMTSS Report

Risk of infertility associated with nonmyeloablative doses of TBI is comparable to the risk with non-TBI conditioning.

BMT survivors are at a 2-fold higher risk of infertility when compared with their closest-age and same-sex matched siblings.

We examine the impact of conditioning intensity (low intensity: nonmyeloablative/reduced intensity vs high intensity: myeloablative) and total body irradiation (TBI) on the probability of live birth after blood or marrow transplantation (BMT). Study participants were drawn from the BMT Survivor Study (BMTSS) and included 1607 transplant survivors between 1974 and 2014 at age ≤45 years, with survival ≥2 years post-BMT and age at study ≥18 years. Closest-age, same-sex biologic siblings (n = 172) were 1:1 matched with 172 survivors. Survivors and siblings self-reported information on sociodemographic, chronic health conditions, and pregnancies. Within survivor analysis: the association between the primary exposure variable (no TBI/low-intensity conditioning; 200 to 800 cGy TBI/low-intensity conditioning; no TBI/high-intensity conditioning; >800 cGy TBI/high-intensity conditioning) and the odds of no post-BMT live birth were examined using multivariable logistic regression, adjusting for clinical and demographic variables. Median age at BMT was 31 years (IQR, 0 to 45), and median length of follow-up was 14.3 years (IQR, 2.4 to 41.4); 39.3% were autologous BMT recipients, and 46.6% were female. Overall, 120 (8.7%) survivors reported post-BMT live births. Receipt of >800 cGy TBI/high-intensity conditioning (odds ratio [OR], 3.7; 95% CI, 1.9-7.0; ref: no TBI/low-intensity conditioning) was associated with higher odds of reporting no live birth post-BMT. In contrast, 200 to 800 cGy TBI/low-intensity conditioning (OR, 1.3; 95% CI, 0.5-3.3), and no TBI/high-intensity conditioning (OR, 0.9; 95% CI, 0.5-1.7) were at similar risk of reporting post-BMT live birth as no TBI/low-intensity conditioning. Comparison with biologic siblings: Using conditional logistic regression, we found that BMT survivors were more likely to report no live birth (OR, 2.0; 95% CI, 1.2-3.3) compared with siblings. These findings could inform conditioning intensity options for patients wishing to preserve fertility post-BMT.

Development of a fertility risk calculator to predict individualized chance of ovarian failure after chemotherapy

PURPOSE

To develop an innovative machine learning (ML) model that predicts personalized risk of primary ovarian insufficiency (POI) after chemotherapy for reproductive-aged women. Currently, individualized prediction of a patient's risk of POI is challenging.

METHODS

Authors of published studies examining POI after gonadotoxic therapy were contacted, and six authors shared their de-identified data (N = 435). A composite outcome for POI was determined for each patient and validated by 3 authors. The primary dataset was partitioned into training and test sets; random forest binary classifiers were trained, and mean prediction scores were computed. Institutional data collected from a cross-sectional survey of cancer survivors (N = 117) was used as another independent validation set.

RESULTS

Our model predicted individualized risk of POI with an accuracy of 88% (area under the ROC 0.87, 95% CI: 0.77-0.96; p < 0.001). Mean prediction scores for patients who developed POI and who did not were 0.60 and 0.38 (t-test p < 0.001), respectively. Highly weighted variables included age, chemotherapy dose, prior treatment, smoking, and baseline diminished ovarian reserve.

CONCLUSION

We developed an ML-based model to estimate personalized risk of POI after chemotherapy. Our web-based calculator will be a user-friendly decision aid for individualizing risk prediction in oncofertility consultations.

Fertility Preservation in Female Pediatric Patients With Cancer: A Clinical and Regulatory Issue

Fertility preservation represents one important goal of cancer patients’ management due to the high impact on health and quality of life of survivors. The available preventive measures cannot be performed in all patients and are not feasible in all health-care facilities. Therefore, the pharmacological treatment with GnRHa has become a valuable non-invasive and well-tolerated alternative, especially in those who cannot access to cryopreservation options due to clinical and/or logistic issues. Supporting data demonstrate a significant advantage for the survivors who received GnRHa in the long-term maintenance of ovarian function and preservation of fertility. The prevention of the risk of ovarian failure with GnRHa is a typical off-label use, defined as the administration of a medicinal product not in accordance with the authorized product information. Italy has officially recognized the off-label use of GnRHa in adult women at risk of premature and permanent menopause following chemotherapy. However, fertility preservation still represents an unmet medical need in adolescents who cannot access to other treatment options.

Long-term Follow-up of Hematopoietic Stem Cell Transplant Survivors: A Focus on Screening, Monitoring, and Therapeutics

Annually, ~50,000 patients undergo hematopoietic stem cell transplantation (HCT) worldwide with almost 22,000 of these patients receiving HCT in the United States. HCT is a curative option for a wide range of hematologic malignancies, and advances in transplantation medicine have resulted in an increase in HCT survivors. It is anticipated that the number of HCT survivors will more than double from 242,000 in 2020 to ~500,000 in 2030. Survivors of HCT are at an increased risk of developing late complications due to exposure to chemotherapy and/or radiation in the pre-, peri-, and post-HCT phases and these cumulative exposures have the potential to damage normal tissue. This tissue damage leads to the early onset of chronic health conditions resulting in premature mortality in HCT survivors, who have a 15-year cumulative incidence of severe or life-threatening chronic health conditions exceeding 40%. Due to the significant burden of morbidity in HCT survivors and the delay in the development of long-term complications, this delicate patient population requires life-long monitoring due to the risk for neuropsychological, cardiac, pulmonary, renal, hepatic, ocular, skeletal, cardiac, endocrine, fertility, and sexual health complications, as well as secondary neoplasms. This review will focus on recent advances in screening, monitoring, and therapeutics for late-occurring or long-term complications in HCT survivors.

Fertility preservation in patients with hematologic malignancies and recipients of hematopoietic cell transplants

Patients with hematologic malignancies and those undergoing hematopoietic cell transplantation (HCT) face a complex set of challenges when considering options for fertility preservation (FP). There are no standard options for prepubertal children, and women with hematologic malignancies may not be eligible for standard FP options. Fortunately, initial therapies for most blood cancers are not highly gonadotoxic, affording an important opportunity for postremission counseling and referrals to fertility specialists. These patients face a high risk of relapse, and many will be referred for autologous or allogeneic HCT, which carries an extremely high risk of infertility. The expanding indications for HCT to include benign hematologic disorders as well as autoimmune diseases mandate that all hematologists are familiar with these risks. Oncofertility researchers are continually pushing the boundaries of what may be possible for our patients; in the meantime, communication and shared decision-making between hematologists and patients, as well as program-building, education, and outreach are essential to ensure that these patients, many of whom will be cured, maintain all of their options for a fulfilling life after intensive therapy.

Gonadotropin-Releasing Hormone Analogs for Gonadal Protection During Gonadotoxic Chemotherapy: A Systematic Review and Meta-Analysis

OBJECTIVE

A systematic review and meta-analysis was conducted to investigate whether gonadotropin-releasing hormone analogs (GnRHa) have a protective role in women treated with alkylating agents.

DATA SOURCES

Major databases (PubMED, EMBASE, Cochrane Central Register of Controlled Trials), systematic snowballing, and trial registries were screened from the inception dates until September 2017.

METHODS AND STUDY SELECTION

Comparative studies involving reproductive-aged women undergoing chemotherapy with or without coadministration of GnRHa were included. Spontaneous menstrual resumption was assessed as a main outcome. Statistical analyses were performed with STATA 14.2 statistical software. Effect estimates were presented as risk ratios (RR) with 95% confidence intervals (CIs).

RESULTS

The literature search yielded 25 436 citations and 84 papers were assessed in full text. Eighteen studies (11 randomized controlled trials [RCTs] and 7 cohort studies) published between 1987 and 2015 were included in the analysis, revealing a significant protective effect of GnRHa (n = 1043; RR:1.38; 95% CI: 1.18-1.63) although with high heterogeneity (I² = 83.3%). Subgroup analyses revealed a significant benefit of GnRHa cotreatment both in RCTs and in cohort studies. Statistical significance was found in all subgroups by the underlying disease, that is, hematological malignancies, autoimmune diseases, and breast cancer. Sensitivity analyses in GnRH agonist-treated patients, in patients younger than 40 years old, and in patients without supradiaphragmatic radiotherapy also revealed a significant benefit of GnRHa cotreatment.

CONCLUSION

Our results indicate that concurrent GnRHa administration is an effective method to decrease gonadotoxicity of alkylating agents. The presence of low-quality evidence favoring gonadoprotective effect requires a strong recommendation for offering GnRHa coadministration to young women who are to undergo gonadotoxic chemotherapy.

CAPSULE

The present systematic review and meta-analysis shows a significant gonadoprotective effect of gonadotropin-releasing hormone analogs in women treated with alkylating agents.

Ovarian function, fertility and reproductive lifespan in cancer patients

INTRODUCTION

The increasing survival of girls and young women after cancer has led to a rapid growth in research into assessment of ovarian function after treatment.

AREAS COVERED

This aim of this review is to discuss normal ovarian function over time, the impact of cancer treatment on ovarian function, the assessment of ovarian reserve after treatment, and pretreatment predictors of ovarian recovery.

EXPERT COMMENTARY

Ovarian function damage after chemotherapy and radiotherapy will impact on fertility and reproductive lifespan, but with great variability. Age at menopause has implications for the duration of estrogen deficiency, with its own adverse health consequences. This has led to identification of the key treatment and patient factors at the time of treatment, notably age and ovarian reserve that impact on post-treatment ovarian function. However, most studies have used outcome measures such as ongoing menses, or biomarkers such as anti-mullerian hormone (AMH), with few reporting on fertility or age at menopause.

Curative therapies: Allogeneic hematopoietic cell transplantation from matched related donors using myeloablative, reduced intensity, and nonmyeloablative conditioning in sickle cell disease

Sickle cell disease (SCD) chronically damages multiple organs over the lifetime of affected individuals. Allogeneic hematopoietic cell transplantation (allo-HCT) is the most studied curative intervention. Fully matched related marrow, peripheral blood derived, or cord blood HCT have the best transplant outcome for symptomatic patients with SCD. For patients with asymptomatic or milder disease who have this donor option available, risks and benefits of HCT should be discussed among the patient, family, treating hematologist, and transplant physician, and decision to proceed to HCT should be individualized. Myeloablative conditioning with busulfan, cyclophosphamide, and ATG has been a commonly employed regimen for children and young adults. Recently, low intensity conditioning with low dose total body irradiation and alemtuzumab is emerging as an efficacious and safe regimen for adults, young adults, and possibly children. Mixed donor chimerism (minimum ≥20% myeloid cells), from myeloablative or nonmyeloablative conditioning regimen, produces robust normal donor erythropoiesis and is sufficient to provide a clinical cure. The proportion of patients remaining on immunosuppression beyond 2 years post-HCT is likely <10% with either myeloablative or low intensity regimens. Late effects from myeloablative or reduced intensity conditioning, or from several more months of immunosuppression in low intensity conditioning may be less common than those observed in HCT for malignant indications. Nonmyeloablative approaches with low toxicities should be the focus of future research efforts. Prevention of GVHD is a shared goal in all approaches of allo-HCT in SCD.

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.

Hormonal Changes and Sexual Dysfunction

Sexual dysfunction is a common concern for many patients with cancer after treatment. Hormonal changes as a result of cancer-directed therapy can affect both male and female sexual health. This has the potential to significantly impact patients' quality of life, but is underreported and undertreated in the oncology setting. This review discusses commonly reported sexual issues and the role that hormonal changes play in this dysfunction. Although medical and psychosocial intervention strategies exist, there is a clear need for further research to formally develop programming that can assist people whose sexual health has been impacted by cancer treatment.

Late effects of blood and marrow transplantation

Hematopoietic cell transplantation is a curative treatment for a variety of hematologic diseases. Advances in transplantation technology have reduced early transplant-related mortality and expanded application of transplantation to older patients and to a wider variety of diseases. Management of late effects after transplantation is increasingly important for a growing number of long-term survivors that is estimated to be half a million worldwide. Many studies have shown that transplant survivors suffer from significant late effects that adversely affect morbidity, mortality, working status and quality of life. Late effects include diseases of the cardiovascular, pulmonary, and endocrine systems, dysfunction of the thyroid gland, gonads, liver and kidneys, infertility, iron overload, bone diseases, infection, solid cancer, and neuropsychological effects. The leading causes of late mortality include recurrent malignancy, lung diseases, infection, secondary cancers and chronic graft-versus-host disease. The aim of this review is to facilitate better care of adult transplant survivors by summarizing accumulated evidence, new insights, and practical information about individual late effects. Further research is needed to understand the biology of late effects allowing better prevention and treatment strategies to be developed.

Current Results and Future Research Priorities in Late Effects after Hematopoietic Stem Cell Transplantation for Children with Sickle Cell Disease and Thalassemia: A Consensus Statement from the Second Pediatric Blood and Marrow Transplant Consortium International Conference on Late Effects after Pediatric Hematopoietic Stem Cell Transplantation

Sustained donor engraftment after allogeneic hematopoietic cell transplantation (HCT) converts to healthy donor hemoglobin synthesis and halts disease symptoms in patients with sickle cell disease and thalassemia major. A disease-free survival probability that exceeds 90% has been reported when HCT using an HLA-matched sibling donor is performed in young patients with low-risk disease or treatment-related risk factors. Alternate donor HCT and HCT in adults is performed infrequently because of a higher risk profile. Transplant-specific risks include conditioning regimen-related toxicity, graft-versus-host disease, graft rejection with marrow aplasia or disease recurrence, and infections associated with immunosuppression and delayed immune reconstitution. The magnitude of risk depends on patient age, clinical status of the underlying disease (eg, organ injury from vasculopathy and iron overload), donor source, and intensity of the conditioning regimen. These risks are commonly monitored and reported in the short term. Documenting very late outcomes is important, but these data are rarely reported because of challenges imposed by patient drop-out and insufficient resources. This report summarizes long-term follow-up results after HCT for hemoglobin disorders, identifies gaps in knowledge, and discusses opportunities for future investigations. This consensus summary will be followed by a second article detailing comprehensive long-term follow-up recommendations to aid in maintaining health in these individuals and identifying late complication risks that could facilitate interventions to improve outcomes.