Germline genetic variants and pediatric rhabdomyosarcoma outcomes: a report from the Children's Oncology Group

BACKGROUND

Relative to other pediatric cancers, survival for rhabdomyosarcoma (RMS) has not improved in recent decades, suggesting the need to enhance risk stratification. Therefore, we conducted a genome-wide association study for event-free survival (EFS) and overall survival (OS) to identify genetic variants associated with outcomes in individuals with RMS.

METHODS

The study included 920 individuals with newly diagnosed RMS who were enrolled in Children's Oncology Group protocols. To assess the association of each single nucleotide polymorphism (SNP) with EFS and OS, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) using multivariable Cox proportional hazards models, adjusted for clinical covariates. All statistical tests were two sided. We also performed stratified analyses by histological subtype (alveolar and embryonal RMS) and carried out sensitivity analyses of statistically significant SNPs by PAX3/7-FOXO1 fusion status and genetic ancestry group.

RESULTS

We identified that rs17321084 was associated with worse EFS (HR = 2.01, 95% CI = 1.59 to 2.53, P = 5.39 × 10-9) and rs10094840 was associated with worse OS (HR = 1.84, 95% CI = 1.48 to 2.27, P = 2.13 × 10-8). Using publicly available data, we found that rs17321084 lies in a binding region for transcription factors GATA2 and GATA3, and rs10094840 is associated with SPAG1 and RNF19A expression. We also identified that CTNNA3 rs2135732 (HR = 3.75, 95% CI = 2.34 to 5.99, P = 3.54 × 10-8) and MED31 rs74504320 (HR = 3.21, 95% CI = 2.12 to 4.86, P = 3.60 × 10-8) were associated with worse OS among individuals with alveolar RMS.

CONCLUSIONS

We demonstrated that common germline variants are associated with EFS and OS among individuals with RMS. Additional replication and investigation of these SNP effects may further support their consideration in risk stratification protocols.

Fertility-related worry among emerging adult cancer survivors

PURPOSE

Cancer survivors with a history of gonadotoxic treatment are at risk for future infertility and reproductive concerns, including worry about infertility. The purpose of this study was to describe factors associated with fertility-related worry among emerging adult survivors of childhood cancer.

METHODS

This chart review included patients aged 18.00-25.99 years and > 1 year from cancer treatment completion with a history of gonadotoxic treatment. Survivors were offered structured fertility-focused discussions at age ≥ 18 years, which assessed worry about future infertility. Data from this discussion (i.e., reported fertility-related worry (yes/no), sociodemographic, and clinical characteristics were abstracted from the medical record. Multivariable logistic regression with backwards elimination was used to calculate odds ratios (OR) and 95% confidence intervals (95%CI) for factors associated with fertility-related worry.

RESULTS

Survivors (N = 249) were a mean age of 19.1 ± 1.2 years at initial fertility discussion; 55.8% were male, 58.2% non-Hispanic White, and 27.3% were at high risk for future treatment-related infertility. Fertility-related worry was reported by 66.3% of survivors. Factors related to worry on multivariable analysis included female sex (OR: 2.64, 95%CI: 1.44-4.96, p = .002), solid tumor diagnosis (OR: 2.31, 95%CI: 1.15-4.71, p = .019), moderate and high risk of infertility (OR: 2.94, 95%CI: 1.23-7.64, p = .02; OR: 3.25, 95%CI: 1.55-7.17, p = .002), and ≥ 2 fertility discussions during survivorship care OR: 2.71, 95%CI: 1.46-5.20, p = .002).

CONCLUSIONS

Two-thirds of emerging adult cancer survivors expressed worry about future infertility, which has been linked to a variety of adverse quality of life outcomes. Survivors who are worried about infertility may benefit from psychological interventions.

Wee1 kinase inhibitor adavosertib with radiation in newly diagnosed diffuse intrinsic pontine glioma: A Children's Oncology Group phase I consortium study

Background

Children with diffuse intrinsic pontine gliomas (DIPG) have a dismal prognosis. Adavosertib (AZD1775) is an orally available, blood-brain barrier penetrant, Wee1 kinase inhibitor. Preclinical efficacy against DIPG is heightened by radiation induced replication stress.

Methods

Using a rolling six design, 7 adavosertib dose levels (DLs) (50 mg/m2 alternating weeks, 50 mg/m2 alternating with weeks of every other day, 50 mg/m2, then 95, 130, 160, 200 mg/m2) were assessed. Adavosertib was only given on days of cranial radiation therapy (CRT).The duration of CRT (54 Gy over 30 fractions; 6 weeks) constituted the dose limiting toxicity (DLT) period. Endpoints included tolerability, pharmacokinetics, overall survival (OS) and peripheral blood γH2AX levels as a marker of DNA damage.

Results

A total of 46 eligible patients with newly diagnosed DIPG [median (range) age 6 (3-21) years; 52% female] were enrolled. The recommend phase 2 dose (RP2D) of adavosertib was 200 mg/m2/d during days of CRT. Dose limiting toxicity included ALT elevation (n = 1, DL4) and neutropenia (n = 1, DL7). The mean Tmax, T1/2 and Clp on Day 1 were 2 h, 4.4 h, and 45.2 L/hr/m2, respectively. Modest accumulation of adavosertib was observed comparing day 5 versus day 1 AUC0-8h (accumulation ratio = 1.6). OS was 11.1 months (95% CI: 9.4, 12.5) and did not differ from historical control.

Conclusion

Adavosertib in combination with CRT is well tolerated in children with newly diagnosed DIPG, however, compared to historical controls, did not improve OS. These results can inform future trial design in children with high-risk cancer.