Second solid cancers after allogeneic hematopoietic cell transplantation using reduced-intensity conditioning

Busulfan-fludarabine versus busulfan-cyclophosphamide for allogeneic transplant in acute myeloid leukemia: long term analysis of GITMO AML-R2 trial

We report the long-term results of a randomized trial (GITMO, AML-R2), comparing 1:1 the combination of busulfan and cyclophosphamide (BuCy2, n = 125) and the combination of busulfan and fludarabine (BuFlu, n = 127) as conditioning regimen in acute myeloid leukemia patients (median age 51 years, range 40-65) undergoing allogeneic hematopoietic stem cell transplantation. With a median follow-up of 6 years, significantly better non-relapse mortality (NRM) was confirmed in BuFlu recipients, which is sustained up to 4 years after transplant (10% vs. 20%, p = 0.0388). This difference was higher in patients older than 51 years (11% in BuFlu vs. 27% in BuCy2, p = 0.0262). The cumulative incidence of relapse, which was the first cause of death in the entire study population, did not differ between the two randomized arms. Similarly, the leukemia-free survival (LFS) and overall survival (OS) were not different in the two cohorts, even when stratifying patients per median age. Graft-and relapse-free survival (GRFS) in BuFlu arm vs. the BuCy2 arm was 25% vs. 20% at 4 years and 20% vs. 17% at 10 years. Hence, the benefit gained by NRM reduction is not offsets by an increased relapse. Leukemia relapse remains a major concern, urging the development of new therapeutic approaches.

MASCC/ISOO Clinical Practice Statement: The risk of secondary oral cancer following hematopoietic cell transplantation

PURPOSE

A MASCC/ISOO Clinical Practice Statement (CPS) is aimed at generating a concise tool for clinicians that concentrates practical information needed for the management of oral complications of cancer patients. This CPS is focused on the risk of secondary oral cancer following hematopoietic cell transplantation (HCT).

METHODS

This CPS was developed based on critical evaluation of the literature followed by a structured discussion of a group of leading experts, members of the Oral Care Study Group of MASCC/ISOO. The information is presented in the form of succinct bullets to generate a short manual about the best standard of care.

RESULTS

Studies described a 7-16-fold higher risk of secondary oral cancer (mainly squamous cell carcinoma) in allogeneic HCT (alloHCT) recipients, particularly in those who developed chronic graft versus host disease (cGVHD). Risk increases over time and is influenced by several risk factors. In autologous HCT, oral cancer risk seemed only slightly elevated.

CONCLUSION

Clinicians should be aware of the higher oral cancer risk in alloHCT survivors, and emphasize the importance of lifelong oral cancer surveillance (at least every 6-12 months) and avoiding cancer promoting lifestyle factors in an empathic way, particularly of those with (a history of) cGVHD. Post-HCT for Fanconi anemia or dyskeratosis congenita, education and rigorous follow-up is even more crucial. In case of suspected oral lesions in the presence of oral mucosal cGVHD, a GVHD intervention may facilitate diagnosis. Suspected lesions should be biopsied. More research is needed on the role of HPV in oral cancer post-HCT.

Skin cancer risk after hematopoietic stem cell transplantation: a systematic review and meta-analysis

Hematopoietic stem cell transplantation (HSCT) has improved outcomes for severe hematologic, malignant, and immune disorders, yet poses an increased risk of subsequent malignancies. This study aimed to examine the risk of skin cancer following HSCT and identify potential risk factors. The search was conducted in MEDLINE, EMBASE, and CINAHL databases until December 2023. Cohort studies reporting standardized incidence ratios (SIRs) for post-HSCT skin cancer or investigating risk factors were included. SIRs, or hazard ratios (HRs) with 95% confidence interval (CI), were calculated using random-effects inverse-variance models. Outcome endpoints were SIRs of skin cancer post-HSCT and risk factors, including gender, chronic graft-versus-host disease (cGVHD), voriconazole exposure, and total body irradiation (TBI). Twenty-six studies involving 164,944 HSCT recipients (allogeneic HSCT, n = 68,637; autologous HSCT, n = 95,435; mean age: 38.5 ± 13.8 years; 71,354 females [43.3%]) were analyzed. Overall, SIR for skin cancer post-HSCT was 7.21 (95% CI 3.98-13.08), with SIRs of 2.25 (95% CI: 1.37-3.68) for autologous HSCT, and 10.18 (95% CI 5.07-20.43) for allogeneic HSCT. Risk factors for skin cancer risk included cGVHD (HR = 2.86 [95% CI: 2.01-4.07]), specifically for basal cell and squamous cell carcinoma (SCC) (HR = 1.80 [95% CI: 1.31-2.46] and HR = 3.68 [95% CI: 2.39-5.68], respectively), male gender (HR = 1.56 [95% CI: 1.15-2.13]), especially for SCC (HR = 1.70 [95% CI: 1.03-2.80]), and voriconazole exposure (HR = 2.01 [95% CI: 1.12-3.61]). TBI showed no statistically significant association with subsequent skin cancer (HR = 1.12 [95% CI: 0.73-1.71]). These findings highlight the importance of rigorous skin cancer surveillance and preventive strategies in HSCT recipients, particularly in male individuals undergoing allogeneic transplants and those with identifiable risk factors, to enable early detection and intervention.

International recommendations for screening and preventative practices for long-term survivors of transplantation and cellular therapy: a 2023 update

As hematopoietic cell transplantation (HCT) and cellular therapy expand to new indications and international access improves, the volume of HCT performed annually continues to rise. Parallel improvements in HCT techniques and supportive care entails more patients surviving long-term, creating further emphasis on survivorship needs. Survivors are at risk for developing late complications secondary to pre-, peri- and post-transplant exposures and other underlying risk-factors. Guidelines for screening and preventive practices for HCT survivors were originally published in 2006 and updated in 2012. To review contemporary literature and update the recommendations while considering the changing practice of HCT and cellular therapy, an international group of experts was again convened. This review provides updated pediatric and adult survivorship guidelines for HCT and cellular therapy. The contributory role of chronic graft-versus-host disease (cGVHD) to the development of late effects is discussed but cGVHD management is not covered in detail. These guidelines emphasize special needs of patients with distinct underlying HCT indications or comorbidities (e.g., hemoglobinopathies, older adults) but do not replace more detailed group, disease, or condition specific guidelines. Although these recommendations should be applicable to the vast majority of HCT recipients, resource constraints may limit their implementation in some settings.

International Recommendations for Screening and Preventative Practices for Long-Term Survivors of Transplantation and Cellular Therapy: A 2023 Update

As hematopoietic cell transplantation (HCT) and cellular therapy expand to new indications and international access improves, the number of HCTs performed annually continues to rise. Parallel improvements in HCT techniques and supportive care entails more patients surviving long term, creating further emphasis on survivorship needs. Survivors are at risk for developing late complications secondary to pretransplantation, peritransplantation, and post-transplantation exposures and other underlying risk factors. Guidelines for screening and preventive practices for HCT survivors were originally published in 2006 and then updated in 2012. An international group of experts was convened to review the contemporary literature and update the recommendations while considering the changing practices of HCT and cellular therapy. This review provides updated pediatric and adult survivorship guidelines for HCT and cellular therapy. The contributory role of chronic graft-versus-host disease (cGVHD) to the development of late effects is discussed, but cGVHD management is not covered in detail. These guidelines emphasize the special needs of patients with distinct underlying HCT indications or comorbidities (eg, hemoglobinopathies, older adults) but do not replace more detailed group-, disease-, or condition-specific guidelines. Although these recommendations should be applicable to the vast majority of HCT recipients, resource constraints may limit their implementation in some settings.

Cutaneous malignancies in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a common lymphoid malignancy that is associated with an increased risk of developing cutaneous malignancies. Clinical outcomes for these malignancies, including melanoma and keratinocyte cancers (KC), are worse for patients with CLL. Individuals with CLL develop an immunodeficiency of both the adaptive and innate immune system, which plays a role in the increased prevalence of skin cancers. This review focuses on the complex interplay between genetics, immunity, and pathogens that influence the cellular composition and biology of skin tumors and their microenvironment in CLL patients, and in comparison with other chronic hematological malignancies. It is paramount for dermatologists to be aware of the association between CLL (and chronic hematological malignancies more broadly) and cutaneous malignancies. This is a high-risk population who require regular and vigorous dermatologic follow-up.

[Secondary cancers following allogeneic hematopoietic stem cell transplantation: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

The Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) held the 13th edition of the Clinical Practices Harmonization Workshops. Our workgroup reviewed the current data on the incidence, screening methods and international guidelines for the prevention of secondary solid cancers following allogeneic hematopoietic stem cell transplantation. The purpose of this workshop was to provide recommendations for the screening and prevention of secondary malignancies to Francophone transplantation centers.

Molecular disparity of HLA-DPB1 is associated with the development of subsequent solid cancer after allogeneic hematopoietic stem cell transplantation

BACKGROUND

An increased incidence of subsequent solid cancers (SSCs) has been reported in long-term survivors of allogeneic hematopoietic stem cell transplantation (allo-HSCT), and SSC is associated with inferior mortality and morbidity. Previous studies showed that the incidence of SSC is significantly higher in those who underwent allo-HSCT from HLA-mismatched donors, suggesting that persistent alloimmunity may predispose patients to SSCs. It was recently reported that, in a cohort of patients who received allo-HSCT from an unrelated donor matched at HLA-A, -B, -C, -DRB1/3/4/5, and -DQB1 loci, HLA-DPB1 alloimmunity determined by high mismatched eplets (MEs) and Predicted Indirectly Recognizable HLA Epitopes (PIRCHE) score (PS), was associated with relapse protection and increased risk of acute graft-versus-host disease (GVHD).

METHODS

In the present study, the impact of HLA-DPB1 alloimmunity assessed by molecular mismatch algorithms on the development of SSCs in a cohort of 1514 patients who underwent allo-HSCT for hematologic malignancies was further investigated. ME load at the HLA-DPB1 locus was measured using the HLAMatchmaker module incorporated in HLA Fusion software, and the PS for mismatched HLA-DPB1 was calculated using the HSCT module from the PIRCHE online matching service.

RESULTS

In multivariable analysis after adjusting for baseline risk factors, higher ME, PS-I, and PS-II in the GVH direction, but not in the HVG direction, were associated with an increased risk of SSCs (ME: subdistribution hazard ratio [SHR] 1.58, p = .01; PS-I: SHR 1.59, p = .009; PS-II: SHR 1.71, p = .003). In contrast, nonpermissive HLA-DPB1 mismatches defined by the conventional T-cell epitope algorithm were not predictive of the risk of SSCs. Moreover, posttransplant cyclophosphamide-based GVHD prophylaxis was associated with a reduced risk of subsequent solid cancer (SHR 0.34, p = .021).

CONCLUSIONS

These results indicate for the first time that increased GVH alloreactivity could contribute to the development of SSCs in allo-HSCT survivors.

Second malignant neoplasms in lymphomas, secondary lymphomas and lymphomas in metabolic disorders/diseases

With inconsistent findings, evidence has been obtained in recent years that metabolic disorders are closely associated with the development of lymphomas. Studies and multiple analyses have been published also indicating that some solid tumor survivors develop a secondary lymphoma, whereas some lymphoma survivors subsequently develop a second malignant neoplasm (SMN), particularly solid tumors. An interaction between the multiple etiologic factors such as genetic factors and late effects of cancer therapy may play an important role contributing to the carcinogenesis in patients with metabolic diseases or with a primary cancer. In this review, we summarize the current knowledge of the multiple etiologic factors for lymphomagenesis, focusing on the SMN in lymphoma, secondary lymphomas in primary cancers, and the lymphomas associated to metabolic disorders/diseases, which have been received less attention previously. Further, we also review the data of coexistence of lymphomas and hepatocellular carcinoma (HCC) in patients with infection of hepatitis C virus and hepatitis B virus.

Male-Specific Late Effects in Adult Hematopoietic Cell Transplantation Recipients: A Systematic Review from the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation

Male-specific late effects after hematopoietic cell transplantation (HCT) include genital chronic graft-versus-host disease (GVHD), hypogonadism, sexual dysfunction, infertility, and subsequent malignancies, such as prostate, penile, and testicular cancer. These effects may be closely intertwined and cause prolonged morbidity and decreased quality of life after HCT. Here we provide a systematic review of male-specific late effects in a collaboration among transplantation physicians, endocrinologists, urologists, dermatologists, and sexual health professionals through the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and the Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation. We used a systematic review methodology to summarize incidence, risk factors, screening, prevention, and treatment of these complications and provide consensus evidence-based recommendations for clinical practice and future research. Most of the evidence regarding male GVHD is still based on limited data, precluding strong therapeutic recommendations. Therefore, we recommend systematic screening for male genital GVHD regularly and reporting of cases to large registries to allow for a better understanding. Future research also should address treatment, given the little published evidence currently available. Male-specific endocrine consequences of HCT include hypogonadism, which also may affect bone health. Given the scanty evidence, current recommendations for hormone substitution and/or bone health treatment are based on similar principles as for the general population. Following HCT, sexual health decreases, and this topic should be addressed at regular intervals. Future studies should focus on interventional strategies to address sexual dysfunction. Infertility remains prevalent in patients having undergone myeloablative conditioning, warranting the offer of sperm preservation for all HCT candidates. Most studies on fertility rely on descriptive registry analysis and surveys, underscoring the importance of reporting post-HCT conception data to large registries. Although the quality of evidence is low, the development of cancer in male genital organs does not seem more prevalent in HCT recipients compared with the general population; however, subsequent malignancies in general seem to be more prevalent in males than in females, and special attention should be given to skin and oral mucosa. Male-specific late effects, which likely are more underreported than female-specific complications, should be systematically considered during the regular follow-up visits of male survivors who have undergone HCT. Care of patients with male-specific late effects warrants close collaboration between transplantation physicians and specialists from other involved disciplines. Future research should be directed toward better data collection on male-specific late effects and on studies about the interrelationships among these late effects, to allow the development of evidence-based effective management practices.

Male-specific late effects in adult hematopoietic cell transplantation recipients: a systematic review from the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation

Male-specific late effects after hematopoietic cell transplantation (HCT) include genital chronic graft-versus-host disease (GvHD), hypogonadism, sexual dysfunction, infertility, and subsequent malignancies. They may be closely intertwined and cause prolonged morbidity and decreased quality of life after HCT. We provide a systematic review of male-specific late effects in a collaboration between transplant physicians, endocrinologists, urologists, dermatologists, and sexual health professionals through the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research, and the Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation. The systematic review summarizes incidence, risk factors, screening, prevention and treatment of these complications and provides consensus evidence-based recommendations for clinical practice and future research.

In-vivo T-cell depleted reduced-intensity conditioned allogeneic haematopoietic stem-cell transplantation for patients with acute lymphoblastic leukaemia in first remission: results from the prospective, single-arm evaluation of the UKALL14 trial

BACKGROUND

The outcome of chemotherapy in patients older than 40 years with acute lymphoblastic leukaemia is poor and myeloablative allogeneic haematopoietic stem-cell transplantation (HSCT) has a high transplant-related mortality (TRM) in this age cohort. The aim of this study was to assess the activity and safety of reduced-intensity conditioned allogeneic HSCT in this patient population.

METHODS

This was a single-arm, prospective study within the UKALL14 trial done in 46 centres in the UK, which recruited patients to the transplantation substudy. Participants in UKALL14 had B-cell or T-cell acute lymphoblastic leukaemia, were aged 25-65 years (BCR-ABL1-negative) or 18-65 years (BCR-ABL1-positive), and for this subcohort had a fit, matched sibling donor or an 8 out of 8 allelic matched unrelated donor (HLA-A, HLA-B, HLA-C, and HLA-DR). On June 20, 2014, the protocol was amended to allow 7 out of 8 matched unrelated donors if the patient had high risk cytogenetics or was minimal residual disease (MRD)-positive after the second induction course. Patients were given fludarabine, melphalan, and alemtuzumab (FMA; intravenous fludarabine 30 mg/m² on days -6 to -2, melphalan 140 mg/m² on day -2, and alemtuzumab 30 mg on day -1 [sibling donor] and days -2 and -1 [unrelated donor]) before allogeneic HSCT (aged ≥41 years patient pathway). Donor lymphocyte infusions were given from 6 months for mixed chimerism or MRD. The primary endpoint was event-free survival and secondary and transplantation-specific endpoints included overall survival, relapse incidence, TRM, and acute and chronic graft-versus-host disease (GVHD). This study is registered with ClinicalTrials.gov, NCT01085617.

FINDINGS

From Feb 22, 2011, to July 26, 2018, 249 patients (236 aged ≥41 years and 13 younger than 41 years) considered unfit for a myeloablative allograft received an FMA reduced-intensity conditioned HSCT. 138 (55%) patients were male and 111 (45%) were female. 88 (35%) participants received transplantations from a sibling donor and 160 (64%) received transplantations from unrelated donors. 211 (85%) participants had B-precursor acute lymphoblastic leukaemia. High-risk cytogenetics were present in 43 (22%) and another 63 (25%) participants were BCR-ABL1-positive. At median follow-up of 49 months (IQR 36-70), 4-year event-free survival was 46·8% (95% CI 40·1-53·2) and 4-year overall survival was 54·8% (48·0-61·2). 4-year cumulative incidence of relapse was 33·6% (27·9-40·2) and 4-year TRM was 19·6% (15·1-25·3). 27 (56%) of 48 patients with TRM had infection as the named cause of death. Seven (15%) of 48 patients had fungal infections, 13 (27%) patients had bacterial infections (six gram-negative), and 11 (23%) had viral infections (three cytomegalovirus and two Epstein-Barr virus). Acute GVHD grade 2-4 occurred in 29 (12%) of 247 patients and grade 3-4 occurred in 12 (5%) patients. Chronic GVHD incidence was 84 (37%) of 228 patients (50 [22%] had extensive chronic GVHD). 49 (30%) of 162 patients had detectable end-of-induction MRD, which portended worse outcomes with event-free survival (HR 2·40 [95% CI 1·46-3·93]) and time-to-relapse (HR 2·41 [1·29-4·48]).

INTERPRETATION

FMA reduced-intensity conditioned allogeneic HSCT in older patients with acute lymphoblastic leukaemia in first complete remission provided good disease control with moderate GVHD, resulting in better-than-expected event-free survival and overall survival in this high-risk population. Strategies to reduce infection-related TRM will further improve outcomes.

FUNDING

Cancer Research UK.

Primary mesenchymal stromal cells in co-culture with leukaemic HL-60 cells are sensitised to cytarabine-induced genotoxicity, whilst leukaemic cells are protected

Tumour microenvironments are hallmarked in many cancer types. In haematological malignancies, bone marrow (BM) mesenchymal stromal cells (MSC) protect malignant cells from drug-induced cytotoxicity. However, less is known about malignant impact on supportive stroma. Notably, it is unknown whether these interactions alter long-term genotoxic damage in either direction. The nucleoside analogue cytarabine (ara-C), common in haematological therapies, remains the most effective agent for acute myeloid leukaemia, yet one third of patients develop resistance. This study aimed to evaluate the bidirectional effect of MSC and malignant cell co-culture on ara-C genotoxicity modulation. Primary MSC, isolated from patient BM aspirates for haematological investigations, and malignant haematopoietic cells (leukaemic HL-60) were co-cultured using trans-well inserts, prior to treatment with physiological dose ara-C. Co-culture genotoxic effects were assessed by micronucleus and alkaline comet assays. Patient BM cells from chemotherapy-treated patients had reduced ex vivo survival (P = 0.0049) and increased genotoxicity (P = 0.3172) than untreated patients. It was shown for the first time that HL-60 were protected by MSC from ara-C-induced genotoxicity, with reduced MN incidence in co-culture as compared to mono-culture (P = 0.0068). Comet tail intensity also significantly increased in ara-C-treated MSC with HL-60 influence (P = 0.0308). MSC sensitisation to ara-C genotoxicity was also demonstrated following co-culture with HL60 (P = 0.0116), which showed significantly greater sensitisation when MSC-HL-60 co-cultures were exposed to ara-C (P = 0.0409). This study shows for the first time that malignant HSC and MSC bidirectionally modulate genotoxicity, providing grounding for future research identifying mechanisms of altered genotoxicity in leukaemic microenvironments. MSC retain long-term genotoxic and functional damage following chemotherapy exposure. Understanding the interactions perpetuating such damage may inform modifications to reduce therapy-related complications, such as secondary malignancies and BM failure.

Adverse Effects of Busulfan Plus Cyclophosphamide versus Busulfan Plus Fludarabine as Conditioning Regimens for Allogeneic Bone Marrow Transplantation

BACKGROUND

The side effects of conditioning regimens on the success rate of allogeneic transplantation around the world have been challenging. In this study, we aimed to investigate the side effect of Bu/Cy and Bu/Flu regimens on our patients who underwent allogeneic bone marrow transplantation.

METHODS

We analyzed 180 patients receiving bone marrow transplantation in Taleghani Hospital, in Tehran, Iran between April 2016 and December 2019. Patients in group A received a combination of intravenous busulfan 0.8 mg/kg QID over two hours for 4 consecutive days (12.8 mg/kg in total)(Savani et al., 2006) and cyclophosphamide 60 mg/kg per day for two consecutive days. Patients in group B received busulfan the same as the first group in combination with fludarabine equal to 40 mg/m² per day. Patients were followed up at regular intervals up to two years after transplantation.

RESULT

Various items were evaluated for patients, including cardiopulmonary function, psychological disorders, GVHD, and endocrine disorders such as hypothyroidism, fertility, or gonad dysfunction.  Primary hypothyroidism developed in 13.3% and 11.1% of the Bu/Cy and Bu/Flu groups, respectively (p=0.230). None of the patients in either group experienced infertility or gonad dysfunction. In group A versus group B, pulmonary diseases were detected in  4.4% versus 6.6% of BMT recipients, respectively (p = 0.223). In both groups, mitral and tricuspid regurgitation were observed in patients (8.9% vs. 11.1%; p = 0.189). Incidence of Psychological disorders was no significant difference between the two groups. 32.2% of group A versus 34.45%  of group B had skin and liver GVHD, respectively (p = 0.235).

CONCLUSION

The therapeutic-related adverse effects of the two conditioning regimens in patients who underwent allogeneic bone marrow transplant were almost similar. To improve quality of life and overall survival among BMT patients, careful evaluation of treatment-related complications should be part of the regular follow-up of them.

Risk Factors for Keratinocyte Carcinoma in Recipients of Allogeneic Hematopoietic Cell Transplants

Importance

Allogeneic hematopoietic cell transplant (alloHCT) is known to increase the risk for keratinocyte carcinoma. The extent to which host characteristics, including pigmentary phenotype and UV radiation exposure, contribute is unknown.

Objective

To identify and validate independent risk factors for keratinocyte carcinoma after alloHCT, including those associated with the transplant and the host.

Design, Setting, and Participants

This retrospective cohort study analyzed a consecutive sample of alloHCT recipients from January 1, 2000, to December 31, 2014, at the Mayo Clinic, Rochester, Minnesota (n = 872) and University Hospitals Cleveland Medical Center, Cleveland, Ohio (n = 147). Participants from the Mayo Clinic were randomly allocated (2:1) into discovery (n = 581) and validation (n = 291) cohorts. Time to first keratinocyte carcinoma and information about transplant- and host-associated risk factors were extracted. A multivariate keratinocyte carcinoma risk model was created using a stepwise Cox proportional hazards regression model with P ≤ .05 for entry that incorporated all covariates that were individually statistically significant at α = 0.05 in the discovery cohort. The risk model was first internally validated using the Mayo Clinic validation cohort and then externally validated using the independent cohort of alloHCT recipients at University Hospitals Cleveland Medical Center. Data were analyzed from March 13, 2018, to June 12, 2019.

Exposures

Allogeneic hematopoietic cell transplant.

Main Outcomes and Measures

The primary outcome was time to development of the first cutaneous keratinocyte carcinoma after alloHCT; secondary outcome, time to development of the first individual basal and/or squamous cell carcinoma after alloHCT.

Results

Of the 872 alloHCT recipients identified in the Mayo Clinic cohort (520 men [59.6%]; mean [SD] age, 48.3 [12.6] years), 95 (10.9%) developed keratinocyte carcinoma after alloHCT during 5349 person-years of follow-up. Of the 147 alloHCT recipients in the exernal validation cohort (86 men [58.5%]; mean [SD] age, 47.9 [17.5] years), 18 (12.2%) developed keratinocyte carcinoma after alloHCT in 880 person-years of follow up. Risk factors independently associated with keratinocyte carcinoma after alloHCT included age (hazard ratio [HR] per 10 years, 1.72; 95% CI, 1.21-2.42), chronic lymphocytic leukemia (HR, 2.47; 95% CI, 1.20-5.09), clinically photodamaged skin (HR, 3.47; 95% CI, 1.87-6.41), and history of cutaneous squamous cell carcinoma (HR, 2.60; 95% CI, 1.41-5.91). Harrell concordance statistics were 0.81 (95% CI, 0.72-0.90) and 0.86 (95% CI, 0.74-0.98) for internal and external validation of the keratinocyte carcinoma risk model, respectively.

Conclusions and Relevance

This study found validated independent risk factors for keratinocyte carcinoma after alloHCT that are enriched with host- compared with transplant-associated risk factors. These findings highlight the importance of assessing host-associated risk factors for keratinocyte carcinoma in patients eligible for alloHCT. Future studies should examine whether keratinocyte carcinoma risk stratification before alloHCT may inform long-term surveillance strategies.

The risk of malignancies in patients receiving hematopoietic stem cell transplantation: a systematic review and meta-analysis

INTRODUCTION

Hematopoietic stem cell transplantation (HSCT) is widely used in the treatment of malignant and non-malignant diseases. Due to advances in the number of survivors of this treatment, the number of survivors is increasing, but the late complications of this therapeutic approach such as secondary cancers have been long term and have not been fully controlled.

METHODS

The present meta-analysis study was performed by considering English-language articles in the databases including Web of Science, Scopus and PubMed. This meta-analysis included cohort studies that reported an incidence of cancer following stem cell transplantation (SCT). Random/fixed effect size meta-analyses were used to standardize the incidence ratio for different cancers.

RESULTS

22 studies that evaluated patients receiving SCT (n = 270,063) were included in the study. The study found 9233 cases of cancer after transplantation. Meta-analysis showed that the risk of cancer after SCT was SIR = 1.66 (95% CI 1.47-1.86). The most common cancers observed in SCT recipients were bone tissue, head and neck cancers, and melanoma, with SIRs of 10.04 (3.48-16.61), 6.35 (4.76-7.93) and 3.52 (2.65-4.39), respectively.

CONCLUSION

The meta-analysis findings showed that the risk of secondary cancers after HSCT was significantly increased in most types of cancers. Consequently, diagnostic tests for common cancers should be included in the screening program of these patients for the prevention and early detection of high-risk cancers.

"Risk of de novo or secondary cancer after solid organ or allogeneic haematopoietic stem cell transplantation"

PURPOSE

Solid organ (SOT) and allogeneic haematopoietic stem cell (HSCT) transplant recipients have elevated risks of de novo or secondary cancer. We explored risk factors hereof.

METHODS

Among SOT and HSCT between January 2004 and December 2014, standardised incidence ratio (SIR) of de novo/secondary cancer compared with the Danish population was determined and risk factors were identified using Poisson regression.

RESULTS

During a median of 3.4 (IQR 1.3-6.4) and 2.6 (0.8-5.4) person-years (PY) after SOT and HSCT, a total of 212/1656 (13%) and 75/992 (8%) persons developed cancer; SIR 3.61 (3.0-4.3) and 2.2 (1.6-3.0), resp.). SIR correlated with younger age and was highest for skin and haematological cancers for both types of transplantation. Within the cohort, cancer was associated with older age (adjusted incidence rate ratio > 50 vs ≤ 19 years, among SOT and HSCT: 9.4 (3.4-25.7) and 25.4 (5.1-126.0), resp.) and current elevated C-reactive protein (CRP) (≥ 10 vs < 10 mg/L: 2.5 (1.8-3.4) and 2.3 (1.4-3.9), resp.), but neither with prior cancer nor type of immunosuppressants.

CONCLUSION

Rates of de novo or secondary cancers are elevated in both SOT and HSCT compared with the general population and mainly for skin and haematological cancers. Among transplant recipients, older age and current elevated CRP are risk factors.

Risk factors for the development of cutaneous melanoma after allogeneic hematopoietic cell transplantation

BACKGROUND

Melanoma risk is increased after allogeneic hematopoietic cell transplantation (HCT), but specific risk factors are unknown.

OBJECTIVE

Investigate risk factors for melanoma after allogeneic hematopoietic cell transplantation.

METHODS

We conducted a nested case-control study of 140 melanoma cases and 557 controls (matched by age at HCT, sex, primary disease, survival time) through the Center for International Blood and Marrow Transplant Research.

RESULTS

Melanoma risk was significantly increased among HCT survivors who received total body irradiation-based myeloablative conditioning (multivariable adjusted odds ratio [OR] = 1.77; 95% confidence interval [CI] = 1.00-3.15) or reduced-intensity conditioning containing melphalan (OR = 2.60; 95% CI = 1.13-6.02) or fludarabine (OR = 2.72; 95% CI = 1.02-7.30) versus busulfan-based myeloablative regimens; were diagnosed with acute graft-versus-host disease (GVHD) with stage 2+ skin involvement (OR = 1.92; 95% CI = 1.19-3.10), chronic GvHD without skin involvement (OR = 1.91; 95% CI = 1.03-3.57), or keratinocytic carcinoma (OR = 2.37; 95% CI = 1.16-4.83); and resided in areas with higher ambient ultraviolet radiation (ORtertile3 = 1.64; 95% CI = 1.01-2.67).

LIMITATIONS

Data on individual-level ultraviolet radiation exposure and clinical data on melanoma characteristics were lacking. Additionally, misclassification of melanoma is possible as not all pathology reports were available for review.

CONCLUSION

These results emphasize the importance of adherence to current surveillance guidelines (routine skin examination, photoprotection recommendations), particularly for HCT survivors at highest risk.

Lower Genital Tract Precancer and Cancer in Hematopoietic Cell Transplant Survivors and the Role of HPV: A Systematic Review and Future Perspectives

Female recipients of hematopoietic cell transplant (HCT) may develop lower genital tract (LGT) dysplasia or new malignancies. A comprehensive systematic review to delineate the occurrence and risk factors for post-HCT LGT precancer and cancer in women was conducted via electronic search of the Cochrane Library, PubMed, Embase, Wiley Online Library, from 1990 to 2018. All studies on the risk, presentation, or incidence of LGT (cervix, vulva, vagina) precancer or cancer post-HCT were included. Reviews, case reports, meta-analysis, book chapters, and studies without the relevant clinical outcomes were excluded. Post-HCT incidence and risk factors for developing LGT precancer or cancer were assessed and determined. Twenty-two out of the original 344 studies met the selection criteria. The risk of LGT cancers in allo-HCT recipients was found to be significantly higher than in the general population, with the standardized incidence ratios of 1.5–48 for cervical cancer and from 19 to 287 for dysplasia. Our review portrays an increased risk of premalignant and malignant neoplasms of female LGT, which have an incompletely described epidemiology and outcomes. Similar to other immunocompromised states, HCT recipients require specific cervical screening guidelines and can greatly benefit from HPV vaccinations. However, there is a lack of prospective data regarding optimum cervical screening in HCT recipients and limited programs offer HPV vaccinations worldwide.

Vascular density and inflammatory infiltrate in primary oral squamous cell carcinoma and after allogeneic hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) recipients have been reported to have an increased risk of chronic graft versus host disease (cGVHD) and hematological and solid cancers. Oral manifestations are the first signs of cGVHD observed in the majority of patients, and oropharyngeal cancer is the most frequent secondary malignancy occurred after HSCT. In this study, we have evaluated the inflammatory infiltrate cell content and correlated with the vascular density in patients affected by primary oral squamous cell carcinoma (OSCC) from previous healthy controls and OSCC after cGVHD. Results have demonstrated that patients with OSCC after GVHD show a more consistent inflammatory infiltrate as compared with the OSCC ones. In detail, the inflammatory background composed of CD3-positive T cells, tryptase-positive mast cells, CD31-positive endothelial cells, and CD68-positive macrophages may be more pronounced in the setting of GVHD + OSCC than in the control group. By contrast, CD20-positive B cells and CD1a-positive dendritic cells were more abundant in the latter population. Finally, a positive correlation was found as between vascular density and inflammatory cell infiltration in both GVHD + OSCC and OSCC groups. Overall, these results confirm the role played by immune cells in enhancing tumor progression and angiogenesis and suggest a potential therapeutic strategy involving inhibition of recruitment of immune cells to the tumor microenvironment and blockade of pro-tumoral effects and pro-angiogenic functions.

Second neoplasms in adult patients submitted to haematopoietic stem cell transplantation

BACKGROUND AND OBJECTIVE

Patients submitted to haematopoietic stem cell transplantation (HSCT) are at increased risk of late complications, such as second neoplasm (SN). The incidence and risk factors of SN in patients receiving HSCT at a single centre were analysed.

PATIENTS AND METHODS

The follow-up of adult patients who received a first HSCT (autologous [auto-HSCT] or allogeneic [allo-HSCT]) between January 2000 and December 2015 was reviewed. We collected their demographic characteristics, the primary disease and type of HSCT, and analysed the cumulative incidence of SN and their risk factors.

RESULTS

Of 699 transplanted patients (auto-HSCT, n=451; allo-HSCT, n=248), 42 (6%) developed SN (17 haematological and 25 solid), 31 post-auto-HSCT and 11 post-allo-HSCT. Haematologic SN were more frequent after auto-HSCT than after allo-HSCT. The median time between HSCT and SN was 4.09 years [range 0.07-13.15], with no differences between auto-HSCT and allo-HSCT. The cumulative incidence of SN was 5% (95% CI 3-6) at 5 years, 7% (95% CI 5-10) at 10 years and 11% (95% CI 8-15) at 15 years, without differences according to the type of HSCT. Only the age over 40 years correlated with an increased risk of SN.

CONCLUSIONS

In this series, the incidence of post-HSCT SN was similar to that previously described. Patients submitted to an auto-HSCT showed a higher frequency of haematologic SN. A higher incidence of SN was detected in patients older than 40 at the time of HSCT.

Second Malignancies after Hematopoietic Stem Cell Transplantation

OPINION STATEMENT

Second malignancies are a rare but well-defined late complication after autologous and allogeneic hematopoietic stem-cell transplantation (SCT). Solid malignancies occur in up to 15% of patients 15 years after SCT with myeloablative conditioning, with no plateau in the incidence rates. They are responsible for 5-10% of late deaths after SCT. The incidence is increased with advanced age at SCT. The major risk factors are the use of total body irradiation, which is associated with adenocarcinomas and with chronic graft-versus-host disease which is associated with squamous cell cancers. There is less data on the incidence of second malignancies after reduced-intensity conditioning, but it may not be lower. The types of solid tumors reported in excess include melanoma and other skin cancers; cancers of the oral cavity and head and neck, brain, liver, uterine cervix, thyroid, breast, lung; and possibly gastrointestinal cancers. Therapy-related myeloid neoplasms (t-MN) are more common after autologous SCT and may be related mostly to pre-transplant therapies. Post-transplant lymphoproliferative disease is donor-cell-derived lymphoma that is more common after allogeneic SCT with T-cell depletion or intensive immune-suppression state. Second malignancies are most often treated similarly to the standard therapy for similar malignancies. Lifelong cancer screening and prevention interventions are required for all transplantation survivors.

Hematopoietic stem cell transplantation in children with Griscelli syndrome: A single-center experience

GS2 is a rare autosomal recessive disease characterized by hypopigmentation, variable immunodeficiency with HLH. HSCT is the only curative treatment for GS2. We analyzed the outcome of 10 children with GS2 who underwent HSCT at our center between October 1997 and September 2013. The median age of the patients at transplant was 13.5 months (range, 6-58 months). All of the patients developed HLH before HSCT and received HLH 94 or HLH 2004 protocols. Donors were HLA-identical relatives in 8 patients, HLA-mismatched relatives in 2 patients. Engraftment was achieved in all except one patient. None of the patients developed acute GVHD. Chronic GVHD occurred in one and veno-occlusive disease occurred in four patients. Eight of the patients are under remission without any neurologic sequelae-median time of disease-free survival is 92.4 months. The present study shows successful transplant outcome without long-term neurologic sequelae in patients with GS2 who underwent HSCT from HLA-related donors.

Secondary solid cancer following hematopoietic cell transplantation in patients with thalassemia major

Hematopoietic cell transplant (HCT) recipients have a substantial risk of developing secondary solid cancers (SSCs). The aim of this retrospective study was to compare the incidence of SSC in a monocentric cohort of thalassemia major (TM) patients (n=122) who received HCT versus an hematopoietic cell donor monocentric cohort (n=122) and versus a large multicenter cohort of age- and sex-matched TM patients (n=244) who received conventional therapy. With a median follow-up of 24 years, 8 transplanted patients were diagnosed with SSC at a median of 18 years after HCT and at a median age of 33 years. Three patients died of cancer progression and 5 are living after a follow-up ranging from 10 months to 16 years after SSC diagnosis. The 30-year cumulative incidence of developing SSC was 13.24%. The occurrence of solid cancers in the hematopoietic cell donor cohort was limited to only one case for a significantly lower cumulative incidence (3.23%, P=0.02) and to 3 cases in the cohort of nontransplant patients for a significantly lower cumulative incidence (1.32%, P=0.005). This study shows that the magnitude of increased risk of SST is fourfold to sixfold for patients treated with HCT as compared with hematopoietic cell donors and nontransplant patients.

A review of late complications of allogeneic hematopoietic stem cell transplantations

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an effective and curative treatment of different malignant and non-malignant diseases. Early transplant-related mortality after allo-HSCT has decreased with reduced-intensity conditioning regimens and effective anti-infectious treatments, but late transplant-related mortality is still a problem. Physicians are now paying more attention to late complications that may worsen the quality of life of many transplant recipients. Chronic graft versus host disease (cGVHD) is one of the major causes of late transplant-related mortality after allo-HSCT. This review discusses recent advances that have been made in clinical evaluation and treatment of late transplant-related complications including cGVHD. The different sites of involvement are organs, especially the skin and eye, and the gastrointestinal, endocrinologic, metabolic, renal, cardiologic, pulmonary, connective tissue, and neurological systems. In addition, this review includes infections and secondary malignancies in post-transplant settings that worsen quality of life in long-term follow-ups.

Long-term complications after hematopoietic cell transplantation

The prevalence of autologous and allogeneic hematopoietic cell transplantation (HCT) survivors continues to increase. Among patients whose disease remains in remission for the first 2-5years after transplantation, it is estimated that approximately 80-90% will be alive over the subsequent 10years. However, the relative mortality rates of such patients continue to remain higher than those of their general population peers, with late complications contributing to significant long-term morbidity and mortality. Late effects in HCT survivors include secondary cancers, organ specific complications, late infections, quality of life impairments, psychosocial issues, sexual and fertility concerns, financial toxicity, and issues around return to work/school. A patient-centric and multidisciplinary approach to HCT survivorship care with collaborative and coordinated care from transplant centers and community healthcare providers is necessary to ensure their long-term health. Lifelong follow-up of HCT survivors is recommended, with established guidelines serving as the template for providing screening and preventive care based on patient-specific exposures. This review discussed common late complications, models for care delivery, and gaps and priorities for future research in the field of HCT survivorship.

National Institutes of Health Hematopoietic Cell Transplantation Late Effects Initiative: The Subsequent Neoplasms Working Group Report

Subsequent neoplasms (SN) after hematopoietic cell transplantation (HCT) cause significant patient morbidity and mortality. Risks for specific SN types vary substantially, with particularly elevated risks for post-transplantation lymphoproliferative disorders, myelodysplastic syndrome/acute myeloid leukemia, and squamous cell malignancies. This document provides an overview of the current state of knowledge regarding SN after HCT and recommends priorities and approaches to overcome challenges and gaps in understanding. Numerous factors have been suggested to affect risk, including patient-related (eg, age), primary disease-related (eg, disease type, pre-HCT therapies), and HCT-related characteristics (eg, type and intensity of conditioning regimen, stem cell source, development of graft-versus-host disease). However, gaps in understanding remain for each of these risk factors, particularly for patients receiving HCT in the current era because of substantial advances in clinical transplantation practices. Additionally, the influence of nontransplantation-related risk factors (eg, germline genetic susceptibility, oncogenic viruses, lifestyle factors) is poorly understood. Clarification of the magnitude of SN risks and identification of etiologic factors will require large-scale, long-term, systematic follow-up of HCT survivors with detailed clinical data. Most investigations of the mechanisms of SN pathogenesis after HCT have focused on immune drivers. Expansion of our understanding in this area will require interdisciplinary laboratory collaborations utilizing measures of immune function and availability of archival tissue from SN diagnoses. Consensus-based recommendations for optimal preventive, screening, and therapeutic approaches have been developed for certain SN after HCT, whereas for other SN, general population guidelines are recommended. Further evidence is needed to specifically tailor preventive, screening, and therapeutic guidelines for SN after HCT, particularly for unique patient populations. Accomplishment of this broad research agenda will require increased investment in systematic data collection with engagement from patients, clinicians, and interdisciplinary scientists to reduce the burden of SN in the rapidly growing population of HCT survivors.

Long-term survival and late events after allogeneic stem cell transplantation from HLA-matched siblings for acute myeloid leukemia with myeloablative compared to reduced-intensity conditioning: a report on behalf of the acute leukemia working party of European group for blood and marrow transplantation

Background

Myeloablative (MAC) and reduced-intensity conditioning (RIC) are established approaches for allogeneic stem cell transplantation (SCT) in acute myeloid leukemia (AML). Most deaths after MAC occur within the first 2 years after SCT, while patients surviving leukemia-free for 2 years can expect a favorable long-term outcome. However, there is paucity of data on the long-term outcome (beyond 10 years) and the pattern of late events following RIC due to the relative recent introduction of this approach.

Methods

We analyzed long-term outcomes in a cohort of 1423 AML patients, age ≥50 years, after SCT from HLA-matched siblings, during the years 1997–2005, median follow-up 8.3 years (0.1–17).

Results

The 10-year leukemia-free survival (LFS) was 31 % (95CI, 27–35) and 32 % (28–35) after MAC and RIC, respectively (P = 0.57). The 10-year GVHD/ relapse-free survival (GRFS), a surrogate for quality of life was 22 % (18–25) and 21 % (18–24), respectively (P = 0.79). The 10-year non-relapse mortality (NRM) was higher and relapse rate was lower after MAC, throughout the early and late post-transplant course. The 10-year LFS among 584 patients surviving leukemia-free 2 years after SCT was 71 % (65–76) and 73 % (67–78) after MAC and RIC, respectively (P = 0.76). Advanced leukemia at SCT was the major predictor of LFS subsequent to the 2-year landmark. Relapse was the major cause of late death after both regimens; however, NRM and in particular chronic graft-versus-host disease and second cancers were more common causes of late death after MAC.

Conclusions

Long-term LFS and GRFS are similar after RIC and MAC. Most events after RIC or MAC occur within the first 2 years after SCT. Patients who are leukemia-free 2 years after SCT can expect similar good subsequent outcome after both approaches.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-016-0347-1) contains supplementary material, which is available to authorized users.

Adherence to cancer screening guidelines in Australian survivors of allogeneic blood and marrow transplantation (BMT)

Allogeneic Blood and Marrow Transplant (BMT) survivors are at high risk of secondary cancers. Although current guidelines endorse survivors following Country-specific general population screening recommendations to mitigate this risk, little is known about cancer screening adherence in Australian BMT survivors. We conducted a cross-sectional survey of 441 BMT survivors who were >1 year post transplant, to explore rates of screening for secondary cancers and to identify barriers to cancer screening recommendations. Survey instruments included the Sydney Post-BMT Survey, FACT-BMT, DASS 21, The Chronic Graft versus Host Disease (GVHD) Activity Assessment-Patient Self-Report (Form B), the Lee Chronic GVHD Symptom Scale, Fear of Cancer Recurrence Scale, and The Post Traumatic Growth Inventory. Fifty-seven percent of respondents were male, median age 54 years, and 40% were >6 years post-BMT. Rates of cancer screening adherence were as follows: cervical 63.4%, breast 53.3%, skin 52.4%, and bowel 32.3%. Older BMT survivors and those >2 years post transplant were more likely to undergo cancer screening. Improved quality of life was associated with screening for skin, breast, and cervical cancer. Fear of cancer recurrence negatively impacted on cervical screening. For those who had not undergone screening, the majority reported not being advised to do so by their treatment team. This study is the largest and most comprehensive to date exploring cancer screening adherence in BMT survivors in Australia. These data provide the basis for health service reform to better meet the needs of BMT survivors and provide evidence to support counseling and education of both patients and professionals.

Reduced intensity conditioning allogeneic hematopoietic cell transplantation for adult acute myeloid leukemia in complete remission - a review from the Acute Leukemia Working Party of the EBMT

Acute myeloid leukemia is the most common indication for an allogeneic hematopoietic cell transplant. The introduction of reduced intensity conditioning has expanded the recipient pool for transplantation, which has importantly made transplant an option for the more commonly affected older age groups. Reduced intensity conditioning allogeneic transplantation is currently the standard of care for patients with intermediate or high-risk acute myeloid leukemia and is now most often employed in older patients and those with medical comorbidities. Despite being curative for a significant proportion of patients, post-transplant relapse remains a challenge in the reduced intensity conditioning setting. Herein we discuss the studies that demonstrate the feasibility of reduced intensity conditioning allogeneic transplants, compare the outcomes of reduced intensity conditioning versus chemotherapy and conventional myeloablative conditioning regimens, describe the optimal donor and stem cell source, and consider the impact of post-remission consolidation, comorbidities, center experience, and more intensive (reduced toxicity conditioning) regimens on outcomes. Additionally, we discuss the need for further prospective studies to optimize transplant outcomes.

Second Cancer Risk and Late Mortality in Adult Australians Receiving Allogeneic Hematopoietic Stem Cell Transplantation: A Population-Based Cohort Study

We quantified the risk of second cancer and late mortality in a population-based Australian cohort of 3273 adult (≥15 years) allogeneic hematopoietic stem cell transplant recipients (1992 to 2007). Most recipients received nonradiation-based conditioning and a peripheral blood graft from a matched related donor. Using record linkage with death and cancer registries, 79 second cancers were identified a median of 3.5 years after transplantation. The competing-risk adjusted cumulative incidence of second cancers was 3.35% (95% CI, 2.59 to 4.24) at 10 years, and the cancer risk relative to the matched general population was 2.10 (95% CI, 1.65 to 2.56). We observed an excess risk of melanoma and lip, tongue, esophagus, and soft tissue cancers. Cancer risk relative to the general population was elevated for those transplanted for lymphoma, some leukemia subtypes, and severe aplastic anemia, recipients who developed chronic graft-versus-host disease (cGVHD) and irrespective of radiation-based conditioning or stem cell source. In those alive 2 years after transplantation (n = 1463), the cumulative incidence of late mortality was 22.2% (95% CI, 19.7 to 24.9) at 10 years, and the risk of death relative to the matched general population was 13.8 (95% CI, 12.2 to 15.6). In multivariable modeling, risk of late death was reduced for females compared with males and those transplanted for chronic myeloid leukemia compared with acute myeloid leukemia; risk was increased for recipients with discordant sex donors, cGVHD, those undergoing second transplants, and disease relapse. Adults undergoing allogeneic transplantation have unique cancer and mortality risk profiles that continue to warrant prevention and surveillance activities targeted at high-risk subgroups.

A promising sword of tomorrow: Human γδ T cell strategies reconcile allo-HSCT complications

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is potentially a curative therapeutic option for hematological malignancies. In clinical practice, transplantation associated complications greatly affected the final therapeutical outcomes. Currently, primary disease relapse, graft-versus-host disease (GVHD) and infections remain the three leading causes of a high morbidity and mortality in allo-HSCT patients. Various strategies have been investigated in the past several decades including human γδ T cell-based therapeutical regimens. In different microenvironments, human γδ T cells assume features reminiscent of classical Th1, Th2, Th17, NKT and regulatory T cells, showing diverse biological functions. The cytotoxic γδ T cells could be utilized to target relapsed malignancies, and recently regulatory γδ T cells are defined as a novel implement for GVHD management. In addition, human γδ Τ cells facilitate control of post-transplantation infections and participate in tissue regeneration and wound healing processes. These features potentiate γδ T cells a versatile therapeutical agent to target transplantation associated complications. This review focuses on insights of applicable potentials of human γδ T cells reconciling complications associated with allo-HSCT. We believe an improved understanding of pertinent γδ T cell functions would be further exploited in the design of innovative immunotherapeutic approaches in allo-HSCT, to reduce mortality and morbidity, as well as improve quality of life for patients after transplantation.

Risk of secondary solid malignancies after allogeneic hematopoietic stem cell transplantation and preventive strategies

The risk of secondary solid malignancies is increased after allogeneic hematopoietic stem cell transplantation (HSCT). The risk starts at about 10 years after HSCT and continues even 20 years later. The most common secondary malignancies include squamous cell carcinoma of skin, genitourinary tract and oral cavity; lung and breast cancers. The use of total body irradiation or conditioning chemotherapy, chronic graft-versus-host disease and duration since HSCT can influence the risk of secondary solid malignancies. Secondary solid malignancies are common causes of nonrelapse mortality in long-term survivors and may account for up to 10% of late deaths. Avoiding smoking, alcohol use and excess sun exposure may reduce the risk. Cancer prevention guidelines are largely consensus-driven and follow the recommendations for general population.

Survival of patients who develop solid tumors following hematopoietic stem cell transplantation

Allogeneic hematopoietic cell transplantation is associated with late adverse effects of therapy, including secondary solid cancers. Most reports address risk factors; however outcomes after secondary solid cancer development are incompletely described. Our objective was to estimate survival probabilities for transplant recipients dependent on secondary solid cancer subtype. We used a previously identified and published cohort who developed secondary solid cancers following allogeneic transplant. Follow-up for these 112 previously identified patients was extended and their survival probabilities were studied. Median duration of follow-up from the development of secondary cancer for survivors was 11.9 years (range: 0.8 – 23.4) and 75% were followed greater than 7.0 years. The 5- and 10-year overall survival probabilities were 50% (95% CI: 41 – 60%) and 46% (95% CI: 37 – 57%), respectively. Overall survival varied by secondary cancer type. Secondary cancer was the cause of death in most patients who died following development of melanoma, central nervous system, oral cavity, thyroid, lung, lower gastrointestinal tract, and bone cancers. Extended follow-up allowed for the most comprehensive longitudinal evaluation to date of this rare condition. These findings will enhance clinician ability to predict outcomes and counsel transplant survivors who develop secondary solid cancers.

Secondary solid cancer screening following hematopoietic cell transplantation

Hematopoietic stem cell transplant (HCT) recipients have a substantial risk of developing secondary solid cancers, particularly beyond 5 years after HCT and without reaching a plateau overtime. A working group was established through the Center for International Blood and Marrow Transplant Research and the European Group for Blood and Marrow Transplantation with the goal to facilitate implementation of cancer screening appropriate to HCT recipients. The working group reviewed guidelines and methods for cancer screening applicable to the general population and reviewed the incidence and risk factors for secondary cancers after HCT. A consensus approach was used to establish recommendations for individual secondary cancers. The most common sites include oral cavity, skin, breast and thyroid. Risks of cancers are increased after HCT compared with the general population in skin, thyroid, oral cavity, esophagus, liver, nervous system, bone and connective tissues. Myeloablative TBI, young age at HCT, chronic GVHD and prolonged immunosuppressive treatment beyond 24 months were well-documented risk factors for many types of secondary cancers. All HCT recipients should be advised of the risks of secondary cancers annually and encouraged to undergo recommended screening based on their predisposition. Here we propose guidelines to help clinicians in providing screening and preventive care for secondary cancers among HCT recipients.

High-dose total body irradiation and myeloablative conditioning before allogeneic hematopoietic cell transplantation: time to rethink?

Over the last decade, the care of patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT) has significantly improved, leading to a decrease in deaths related to allo-HCT as well as improved long-term survival. However, for many patients, long-term survivorship is associated with a substantial burden of chronic morbidities. Indeed, malignant and nonmalignant late complications after allo-HCT are numerous and usually multifactorial, with all organs and tissues a potential target. In many cases, these long-term side effects are associated with the use of high-dose total body irradiation, myeloablative conditioning regimens, and the onset of chronic graft-versus-host disease. It appears to be essential to change the natural history of these late effects. This requires the introduction of improved conditioning regimens and the development of lifelong monitoring controls, patient counseling, and preventative treatment measures. This approach will allow us to pursue our efforts to improve patient outcome.