Leonie Wilcox

Second cancer risk in adults receiving autologous haematopoietic SCT for cancer: a population-based cohort study

Population-based evidence on second cancer risk following autologous haematopoietic SCT (HCT) is lacking. We quantified second cancer risk for a national, population-based cohort of adult Australians receiving autologous HCT for cancer and notified to the Australasian Bone Marrow Transplant Recipient Registry 1992–2007 (n=7765). Cancer diagnoses and deaths were ascertained by linkage with the Australian Cancer Database and National Death Index. Standardized incidence ratios (SIRs) were calculated and Cox regression models were used to estimate within-cohort risk factors treating death as a competing risk. During a median 2.5 years follow-up, second cancer risk was modestly increased compared with the general population (SIR 1.4, 95% confidence interval 1.2–1.6); significantly elevated risk was also observed for AML/myelodysplastic syndrome (SIR=20.6), melanoma (SIR=2.6) and non-Hodgkin lymphoma (SIR=3.3). Recipients at elevated risk of any second cancer included males, and those transplanted at a younger age, in an earlier HCT era, or for lymphoma or testicular cancer. Male sex, older age (>45 years) and history of relapse after HCT predicted melanoma risk. Transplantation for Hodgkin lymphoma and older age were associated with lung cancer risk. Second malignancies are an important late effect and these results inform and emphasize the need for cancer surveillance in autologous HCT survivors.

Second cancers and late mortality in Australian children treated by allogeneic HSCT for haematological malignancy

We examined risk of second cancer and late mortality in a population-based Australian cohort of 717 pediatric allogeneic stem cell transplant (HSCT) recipients treated for a malignant disease during 1982–2007. Record linkage with population-based death and cancer registries identified 17 second cancers at a median of 7.9 years post HSCT; thyroid cancer being the most common malignancy (n=8). The cumulative incidence of second cancer was 8.7% at follow-up, and second cancers occurred 20 times more often than in the general population (standardised incidence ratio 20.3, 95% confidence interval (CI)=12.6–32.7). Transplantation using radiation-based conditioning regimens was associated with increased second cancer risk. A total of 367 patients survived for at least 2 years post HSCT and of these 44 (12%) died at a median of 3.1 years after HSCT. Relapse was the most common cause of late mortality (n=32). The cumulative incidence of late mortality was 14.7%. The observed rate of late mortality was 36 times greater than in the matched general population (standardised mortality ratio 35.9, 95% CI=26.7–48.3). Recipients who relapsed or who had radiation-based conditioning regimens were at higher risk of late mortality. Second cancers and late mortality continue to be a risk for pediatric patients undergoing HSCT, and these results highlight the need for effective screening and survivorship programs.

A Population-Based Cohort Study of Late Mortality in Adult Autologous Hematopoietic Stem Cell Transplant Recipients in Australia

We assessed overall and cause-specific mortality and risk factors for late mortality in a nation-wide population-based cohort of 4547 adult cancer patients who survived 2 or more years after receiving an autologous hematopoietic stem cell transplantation (HSCT) in Australia between 1992 and 2005. Deaths after HSCT were identified from the Australasian Bone Marrow Transplant Recipient Registry and through data linkage with the National Death Index. Overall, the survival probability was 56% at 10 years from HSCT, ranging from 34% for patients with multiple myeloma to 90% for patients with testicular cancer. Mortality rates moved closer to rates observed in the age- and sex-matched Australian general population over time but remained significantly increased 11 or more years from HSCT (standardized mortality ratio, 5.9). Although the proportion of deaths from nonrelapse causes increased over time, relapse remained the most frequent cause of death for all diagnoses, 10 or more years after autologous HSCT. Our findings show that prevention of disease recurrence remains 1 of the greatest challenges for autologous HSCT recipients, while the increasing rates of nonrelapse deaths due to the emergence of second cancers, circulatory diseases, and respiratory diseases highlight the long-term health issues faced by adult survivors of autologous HSCT.

Incident cancers and late mortality in Australian children treated by allogeneic stem cell transplantation for non-malignant diseases

Hematopoietic stem cell transplantation (HSCT) is a life‐saving procedure for children with a variety of non‐malignant conditions. However, these children face an increased risk of late death and incident cancers after HSCT, which may occur many years after their initial HSCT.

Activity and Capacity Profile of Transplant Physicians and Centers in Australia and New Zealand

We conducted a study to analyze and report on indicators of hematopoietic cell transplant (HCT) physician time use and HCT center output measures. HCT centers in Australia and New Zealand (A&NZ) were invited to provide demographic and time use details for physicians participating in HCT patient care (HCT physicians). Resource details for adult and pediatric centers were included. From a total of 46 centers that were invited to participate, completed data were received from 37 centers (80%) representing 185 HCT physicians, with a median age of 48 (range, 33 to 72), of whom 31% were women. Just over half of HCT physicians cited prior work experience in large overseas HCT centers (97, 52%) and over one-third (79, 43%) possessed postgraduate qualifications other than specialist training. Total annual mean HCTs per HCT physician full-time equivalent (FTE) were 14.2 for centers performing both allogeneic and autologous HCT, 6.6 for autologous only centers, and 10.6 for all centers. For all HCT physicians surveyed the mean proportion of time spent on HCT related tasks was 31.7%. In A&NZ, for centers that perform both allografts and autografts, there was a mean of 4.0 allogeneic HCT annually per HCT bed, compared with 2.6 for the United States and 7.1 allogeneic HCT annually per HCT physician FTE (United States, 6.3). Projections of the A&NZ HCT physician workforce indicated that the numbers of HCT physicians are likely to stay within the region of 170 to 190 for the next 10 years, whereas HCT activity will likely continue to climb steadily. Healthcare and government authorities should be prepared to enable and support greater HCT activity in A&NZ in the future.

Graft Transit Time Has No Effect on Outcome of Unrelated Donor Hematopoietic Cell Transplants Performed in Australia and New Zealand: A Study from the Australasian Bone Marrow Transplant Recipient Registry

A previous study found that platelet recovery and mortality were worse in recipients of myeloablative bone marrow transplants where graft transit times were longer than 20 hours. This retrospective study of unrelated myeloablative allogeneic transplantation performed within Australia and New Zealand analyzed transplant outcomes according to graft transit times. Of 233 assessable cases, 76 grafts (33%) were sourced from bone marrow (BM) and 157 (67%) from peripheral blood. Grafts sourced from Australia and New Zealand (47% of total) were associated with a median transit time of 6 hours versus 32 hours for overseas sourced grafts (53% of total). Graft transit temperature was refrigerated in 85%, ambient in 6%, and unknown in 9% of cases, respectively. Graft transit times had no significant effect on neutrophil or platelet engraftment, treatment-related mortality, overall survival, and incidence of acute or chronic graft-versus-host disease. Separate analysis of BM grafts, although of reduced power, also showed no significant difference in either neutrophil or platelet engraftment or survival between short and longer transport times. This study gives reassurance that both peripheral blood stem cell and especially BM grafts subjected to long transit times and transported at refrigerated temperatures may not be associated with adverse recipient outcomes.