Toxicity of (neo)adjuvant chemotherapy for BRCA1- and BRCA2-associated breast cancer

The impact of germline BRCA pathogenic variants in locally advanced, triple negative breast cancer treated with platinum-based neoadjuvant chemotherapy

BACKGROUND

Whether germline BRCA (gBRCA) pathogenic variants (PV) affect prognosis of women with triple negative breast cancer (TNBC) and whether it has implications for treatment decisions in the neoadjuvant setting is unclear.

METHODS

This is a retrospective two-center cohort study comprising all women with early stage TNBC who have completed genetic testing and were treated with neoadjuvant dose-dense doxorubicin and cyclophosphamide followed by paclitaxel and carboplatin. All eligible patients treated between 10.2014 and 3.2020 were included. Data on clinico-pathological, pathological response, overall survival (OS) and disease-free survival (DFS) were evaluated. Differences in clinico-pathological features and outcomes were analyzed according to gBRCA status.

RESULTS

Sixty-four women were included in the final analysis, of which 31 had gBRCA PV (gBRCA carriers) and 33 were gBRCA wild-type. Clinico-pathological characteristics were similar between both groups. The odds for pathological complete response (pCR) were significantly higher in gBRCA carriers (74.2%) compared to BRCA wild-type women (48.5%), p = 0.035. At a median follow-up of 30 months, gBRCA carriers had significantly favorable OS (HR = 8.64, 95% CI 1.08-69.21, p = 0.042). The difference in DFS did not reach statistical significance (HR = 7.4, 95% CI 0.91-60.27, p = 0.062). The favorable OS for gBRCA carriers remained significant in multivariate analysis (p = 0.029) and was noted regardless of pathological response (p = 0.018).

CONCLUSION

Compared to wild-type, gBRCA carriers with locally advanced TNBC treated with neoadjuvant chemotherapy containing carboplatin had a higher pCR rate and better outcomes. These results strengthen the contention that gBRCA status should be considered when tailoring treatment decisions in women with locally advanced TNBC.

Chemotherapy-related agranulocytosis as a predictive factor for germline BRCA1 pathogenic variants in breast cancer patients: a retrospective cohort study

BACKGROUND

Carriers of germline pathogenic variants of the BRCA1 gene (gBRCA1) tend to have a higher incidence of haematological toxicity upon exposure to chemotherapy. We hypothesised that the occurrence of agranulocytosis during the first cycle of (neo-)adjuvant chemotherapy (C1) in breast cancer (BC) patients could predict gBRCA1 pathogenic variants.

PATIENTS AND METHODS

The study population included non-metastatic BC patients selected for genetic counselling at Hôpitaux Universitaires de Genève (Jan. 1998 to Dec. 2017) with available mid-cycle blood counts performed during C1. The BOADICEA and Manchester scoring system risk-prediction models were applied. The primary outcome was the predicted likelihood of harbouring gBRCA1 pathogenic variants among patients presenting agranulocytosis during C1.

RESULTS

Three hundred seven BC patients were included: 32 (10.4%) gBRCA1, 27 (8.8%) gBRCA2, and 248 (81.1%) non-heterozygotes. Mean age at diagnosis was 40 years. Compared with non-heterozygotes, gBRCA1 heterozygotes more frequently had grade 3 BC (78.1%; p = 0.014), triple-negative subtype (68.8%; p <0.001), bilateral BC (25%; p = 0.004), and agranulocytosis following the first cycle of (neo-)adjuvant chemotherapy (45.8%; p = 0.002). Agranulocytosis and febrile neutropenia that developed following the first cycle of chemotherapy were independently predictive for gBRCA1 pathogenic variants (odds ratio: 6.1; p = 0.002). The sensitivity, specificity, positive predictive value, and negative predictive value for agranulocytosis predicting gBRCA1 were 45.8% (25.6-67.2%), 82.8% (77.5-87.3%), 22.9% (6.1-37.3%), and 93.4% (88.9-96.4%), respectively. Agranulocytosis substantially improved the positive predictive value of the risk-prediction models used for gBRCA1 evaluation.

CONCLUSION

Agranulocytosis following the first cycle of (neo-)adjuvant chemotherapy is an independent predictive factor for gBRCA1 detection in non-metastatic BC patients.

Association between Breast Cancer Polygenic Risk Score and Chemotherapy-Induced Febrile Neutropenia: Null Results

BACKGROUND

The hypothesis that breast cancer (BC) susceptibility variants are linked to chemotherapy-induced toxicity has been previously explored. Here, we investigated the association between a validated 313-marker-based BC polygenic risk score (PRS) and chemotherapy-induced neutropenia without fever and febrile neutropenia (FNc) in Asian BC patients.

METHODS

This observational case-control study of Asian BC patients treated with chemotherapy included 161 FNc patients, 219 neutropenia patients, and 936 patients who did not develop neutropenia. A continuous PRS was calculated by summing weighted risk alleles associated with overall, estrogen receptor- (ER-) positive, and ER-negative BC risk. PRS distributions neutropenia or FNc cases were compared to controls who did not develop neutropenia using two-sample t-tests. Odds ratios (OR) and corresponding 95% confidence intervals were estimated for the associations between PRS (quartiles and per standard deviation (SD) increase) and neutropenia-related outcomes compared to controls.

RESULTS

PRS distributions were not significantly different in any of the comparisons. Higher PRS_overall quartiles were negatively correlated with neutropenia or FNc. However, the associations were not statistically significant (PRS per SD increase OR neutropenia: 0.91 [0.79-1.06]; FNc: 0.87 [0.73-1.03]). No dose-dependent trend was observed for the ER-positive weighted PRS (PRS_ER-pos) and ER-negative weighted PRS (PRS_ER-neg).

CONCLUSION

BC PRS was not strongly associated with chemotherapy-induced neutropenia or FNc.

Chemotherapy toxicity and activity in patients with pancreatic ductal adenocarcinoma and germline BRCA1-2 pathogenic variants (gBRCA1-2pv): a multicenter survey

BACKGROUND

Germline BRCA1-2 pathogenic variants (gBRCA1-2pv)-related pancreatic ductal adenocarcinoma (PDAC) showed increased sensitivity to DNA cross-linking agents. This study aimed at exploring safety profile, dose intensity, and activity of different chemotherapy regimens in this setting.

PATIENTS AND METHODS

gBRCA1-2pv PDAC patients of any age and clinical tumor stage who completed a first course of chemotherapy were eligible. A descriptive analysis of chemotherapy toxicity, dose intensity, response, and survival outcomes was performed.

RESULTS

A total of 85 gBRCA1-2pv PDAC patients treated in 21 Italian centers between December 2008 and March 2021were enrolled. Seventy-four patients were assessable for toxicity and dose intensity, 83 for outcome. Dose intensity was as follows: nab-paclitaxel 72%, gemcitabine 76% (AG); cisplatin 75%, nab-paclitaxel 73%, capecitabine 73%, and gemcitabine 65% (PAXG); fluorouracil 35%, irinotecan 58%, and oxaliplatin 64% (FOLFIRINOX). When compared with the literature, grade 3-4 neutropenia, thrombocytopenia, and diarrhea were increased with PAXG, and unmodified with AG and FOLFIRINOX. RECIST responses were numerically higher with the three- (81%) or four-drug (73%) platinum-containing regimens that outperformed AG (41%) and oxaliplatin-based doublets (56%). Carbohydrate antigen 19.9 (CA19.9) reduction >89% at nadir was reported in two-third of metastatic patients treated with triplets and quadruplets, as opposed to 33% and 45% of patients receiving oxaliplatin-based doublets or AG, respectively. All patients receiving AG experienced disease progression, with a median progression-free survival (mPFS) of 6.4 months, while patients treated with platinum-containing triplets or quadruplets had an mPFS >10.8 months. Albeit still immature, data on overall survival seemed to parallel those on PFS.

CONCLUSIONS

Our data, as opposed to figures expected from the literature, highlighted that platinum-based regimens provoked an increased toxicity on proliferating cells, when dose intensity was maintained, or an as-expected toxicity, when dose intensity was reduced, while no change in toxicity and dose intensity was evident with AG. Furthermore, an apparently improved outcome of platinum-based triplets or quadruplets over other regimens was observed.

Should the BCRA1/2-mutations healthy carriers be valid candidates for hematopoietic stem cell donation?

It’s still not clear whether the mutational status of BRCA-mutated healthy hematopoietic stem cells (HSCs) donors could have an impact on the engraftment. Comparing the studies present in literature, we focused on the correlation between BRCA mutations and the development of hematological malignancies and Fanconi anemia (FA); then, we explored HSCs types, frequencies, and functions in the presence of BRCA mutations, as well as the reconstitution of hematopoiesis after chemotherapy and radiation treatments. The role of BRCA mutations in the FA showed a possible involvement in the onset of the disease; the mutation carriers, indeed, did not show any sign of the typical phenotype of the FA. BRCA mutational status can be considered as a risk factor for hematological malignancies, but only for secondary malignancies and/or in the presence of bone marrow stress factors. Currently we don’t know if a conditioning regimen could be compensated by BRCA mutated HSCs, even if murine models tried to show the possible differences between fully mutated, haploinsufficient and normal HSCs. Thus, given the downregulating effect of the mutations on hematopoiesis, it could be questionable to use the HSCs of a BRCA-mutated donor in the presence of another available donor with the same compatibility.

Post hoc analyses of GOG 9923: Does BRCA status affect toxicities?: An NRG oncology study

OBJECTIVE

To evaluate how women with epithelial ovarian cancer (EOC), dichotomized by BRCA status, tolerate intravenous (IV) or intraperitoneal (IP) chemotherapy given with veliparib and bevacizumab (bev) on a GOG phase I study (GOG 9923, NCT00989651).

METHODS

This is an unplanned, post hoc analysis of an IRB approved, multi-institutional, prospective study (GOG 9923). Clinical characteristics and toxicity data based on BRCA status were evaluated and descriptive statistics were used to summarize baseline patient characteristics and toxicities. The Kaplan Meier method was used to generate survival estimates.

RESULTS

Four hundred twenty-four patients were evaluable. Patients were treated with IV carboplatin, paclitaxel, and bev every 21 days (regimen 1), weekly IV paclitaxel with carboplatin and bev (regimen 2) or IV paclitaxel and bev with IP cisplatin (regimen 3). Bev was continued as maintenance in all arms. Within each of these regimens, veliparib was given either twice daily for the entirety of each cycle (continuous) or on days -2 to 5 (intermittent). Ten percent of patients treated on regimen 1, 12% on regimen 2, and 19.8% on regimen 3 had BRCA-associated tumors. Patients with BRCA-associated tumors, when compared to wild type, experienced similar rates of anemia, febrile neutropenia (, abdominal pain, colonic perforation, nausea, vomiting, and peripheral sensory neuropathy. Median progression free survival (PFS) was not significantly different between BRCA-associated and wild type cancers (HR 0.96, CI 0.65-1.42), though this study's primary aim was not to evaluate outcomes.

CONCLUSIONS

Germline BRCA mutations positively affect chemosensitivity in EOC, but whether differences in toxicities among BRCA-associated and BRCA wild type tumors existed was previously not reported. In this population with newly diagnosed ovarian cancer no differences in reported toxicity between the two groups was observed.

Germline BRCA1/2 mutations and severe haematological toxicities in patients with breast cancer treated with neoadjuvant chemotherapy

BACKGROUND

BRCA1 and BRCA2 play a central role in DNA repair. Therefore, patients harbouring germline (g) BRCA1/2 mutations (m) treated with chemotherapy might be at higher risk of haematological toxicities.

METHODS

Patients from German Breast Group (GBG) and Arbeitsgemeinschaft Gynäkologische Onkologie-breast group studies with early triple-negative breast cancer (TNBC) and known gBRCA1/2m status treated with anthracycline-taxane-based neoadjuvant chemotherapy were analysed. Primary objective was the rate of neutropenia grade (G)III-IV in cycle 1 (C1). Secondary objectives included effects on overall and other haematological toxicities GIII-IV in C1, cumulative haematological toxicity across all cycles, relative total dose intensity, and granulocyte-colony stimulating factor prophylaxis. Haematological toxicities under taxanes, carboplatin, and cyclophosphamide were explored.

RESULTS

Two hundred nine of 1171 (17.8%) evaluated patients had gBRCA1/2m. In C1, 37.4% gBRCA1/2m versus 35.7% wild-type patients had neutropenia GIII-IV (P = 0.683). For C1, gBRCA1/2m predicted neither for neutropenia GIII-IV (odds ratio [OR]: 1.26, 95% confidence intervals [CI]: 0.87-1.82, P = 0.226) nor for other haematological toxicities GIII-IV (OR: 0.91, 95% CI: 0.64-1.31, P = 0.625) in multivariable regression models. Analyses of cumulative toxicities across all cycles yielded similar results except thrombocytopaenia GIII-IV, which was increased in gBRCA1m patients. In patients treated with taxanes, the rate of haematological toxicities GIII-IV was higher in gBRCA1/2m compared with wild-type (59.5% versus 43.1%; p < 0.001). No difference was seen under cyclophosphamide or platinum-containing chemotherapies.

CONCLUSIONS

gBRCA1/2m was not associated with higher risk of overall severe haematological toxicities in the first cycle or cumulatively across all cycles under standard chemotherapy for TNBC. Under taxane, patients with gBRCA1/2m might have a higher risk of haematological toxicities GIII-IV, requiring further research.

Clinical outcome and toxicity from taxanes in breast cancer patients with BRCA1 and BRCA2 pathogenic germline mutations

Germline variations in genes coding for proteins involved in the oxidative stress and DNA repair greatly influence drug response and toxicity. Because BRCA1 and BRCA2 proteins play a role in DNA damage repair, we postulated that taxane-related toxicity is potentially higher and clinical outcome in different in patients with BRCA pathogenic variants (PV). Seven hundred nineteen women who underwent BRCA genetic testing and were treated with taxane-containing chemotherapy for early-stage breast cancer between 1997 and 2018 were included in the study. Patients with BRCA variants of uncertain significance were excluded. The Kaplan-Meier product-limit method was used to estimate recurrence-free survival (RFS) and overall survival (OS) rates. Logistic regression models were used to assess the association between chemotherapy toxicity and factors of interest. Cox regression models were used to assess the association between RFS and OS and factors of interest. Ninety-four (13%) and 54 (7%) patients had BRCA1 and BRCA2-PVs, respectively. While anemia (P = .0025) and leukopenia (P = .001) were more frequently seen in BRCA noncarriers, there was no difference in regards to peripheral neuropathy or other toxicities between the groups. Increasing doses of taxane were associated with increased risk of neutropenia, stomatitis, nausea, vomiting, acne/rash, and peripheral neuropathy across all groups. In a multivariate logistic regression model, BRCA2 status remained as an independent significant predictor for decreased hematologic toxicity (HR: 0.36; 95% CI: 0.20-0.67; P = .001) and increased gastrointestinal toxicity (HR: 1.93; 95% CI: 1.02-3.67; P = .04). Being overweight, obese and African-American race were significant predictors for peripheral neuropathy (P = .04; P = .03; P = .06, respectively). Total taxane dose received did not have any impact on survival outcomes. Our study demonstrates that taxane-containing chemotherapy regimens do not increase risk of peripheral neuropathy or hematologic toxicity in patients with BRCA PVs. The mechanisms for this finding need to be further investigated as it may provide an opportunity to combine taxanes with other agents, such as platinum salts or PARP inhibitors, with less anticipated toxicity.

Recurrent Germline BRCA2 Gene Mutation in Lithuanian Family

Approximately 10% of all breast cancer (BC) cases are familial and caused by inheritance of mutant BRCA1, BRCA2, or some other genes from the same DNA reparation pathway. Genetic counseling in families with cancer history is a powerful means for early cancer detection and active risk reduction through preventive interventions. This is the first report of the rare inherited BRCA2 frameshift-deletion mutation c.3847_3848delGT in one Lithuanian pedigree with the intense familial history of BC. Three BRCA2-positive blood relatives with BC of different biological types were identified in this pedigree with the same type mutation. All three cases were diagnosed with advanced stage ductal carcinoma. Markedly, polymorphic cells and numerous mitoses were identified in BC from the cases. Two patients from the family were diagnosed with the triple negative tumors, while one case had early onset of the hormone positive BC. Despite the variation in clinical and biological presentation of BC, all cases showed a good response to conventional treatment. In conclusion, the strong influence of BRCA2 mutation on the onset of BC of various biological types reveals the complexity of genetic counselling in families with BC history.

Chemotherapy Toxicity in BRCA Mutation Carriers Undergoing First-Line Platinum-Based Chemotherapy

OBJECTIVE

BRCA mutations are the most frequent mutations causing homologous recombination defects in epithelial ovarian cancers (EOC). Germline mutation carriers are heterozygous for the mutation and harbor one defective allele in all cells. This has been hypothesized to cause increased susceptibility to DNA damage in healthy cells as well as neoplastic ones. Our objective was to assess chemotherapy-associated toxicities in patients with epithelial ovarian cancer with and without a germline BRCA mutation.

MATEIALS AND METHODS

A retrospective cohort study of patients with EOC receiving first-line platinum-based chemotherapy at a single center between 2006 and 2016. Indices of chemotoxicity, including blood counts, transfusion requirements, granulocyte colony-stimulating factor (gCSF) prescriptions, episodes of febrile neutropenia, and treatment delays were compared for BRCA mutation carriers and noncarriers.

RESULTS

A total of 90 women met the inclusion criteria, including 31 BRCA mutation carriers (34%) and 59 noncarriers (66%). Mean hemoglobin, neutrophil count, and platelet counts during treatment were comparable for the two patient groups. There was a trend toward a higher frequency of hematological events in BRCA mutation carriers (neutropenia <1500 per mL: 6% vs. 0%, p = .12; thrombocytopenia <100,000 per mL: 23% vs. 9%, p = .07), but these differences were not statistically significant. Similarly, no significant differences were found in surrogates of bone marrow toxicity such as blood transfusions, use of gCSF, episodes of febrile neutropenia, or treatment delays.

CONCLUSION

BRCA mutation carriers and noncarriers receiving first-line platinum-based chemotherapy for EOC have similar hematologic toxicity profiles. Clinicians treating these patients can be reassured that chemotherapy dosing or schedule do not require adjustment in patients carrying BRCA mutations.

IMPLICATIONS FOR PRACTICE

Patients with ovarian cancer carrying BRCA mutations are more likely to have serous tumors and present with higher CA125 levels. Germline BRCA mutation status is not associated with increased frequency of adverse hematologic events among patients with ovarian cancer being treated with first-line platinum-based chemotherapy. Germline BRCA mutations are also not associated with more treatment delays or a lower number of courses completed in this patient population. These findings should reassure practitioners engaged in care for patients with ovarian cancer that BRCA mutation status most likely will not affect chemotherapy dosing or schedule.

Early prediction of neoadjuvant treatment outcome in locally advanced breast cancer using parametric response mapping and radial heterogeneity from breast MRI

BACKGROUND

Early prediction of nonresponse is essential in order to avoid inefficient treatments.

PURPOSE

To evaluate if parametrical response mapping (PRM)-derived biomarkers could predict early morphological response (EMR) and pathological complete response (pCR) 24-72 hours after initiation of chemotherapy treatment and whether concentric analysis of nonresponding PRM regions could better predict response.

STUDY TYPE

This was a retrospective analysis of prospectively acquired cohort, nonrandomized, monocentric, diagnostic study.

POPULATION

Sixty patients were initially recruited, with 39 women participating in the final cohort.

FIELD STRENGTH/SEQUENCE

A 1.5T scanner was used for MRI examinations.

ASSESSMENT

Dynamic contrast-enhanced (DCE)-MR images were acquired at baseline (timepoint 1, TP1), 24-72 hours after the first chemotherapy (TP2), and after the end of anthracycline treatment (TP3). PRM was performed after fusion of T₁ subtraction images from TP1 and TP2 using an affine registration algorithm. Pixels with an increase of more than 10% of their value (PRMdce+) were corresponding nonresponding regions of the tumor. Patients with a decrease of maximum diameter (%dDmax) between TP1 and TP3 of more than 30% were defined as EMR responders. pCR patients achieved a residual cancer burden score of 0.

STATISTICAL TESTS

T-test, receiver operating characteristic (ROC) curves, and logistic regression were used for the analysis.

RESULTS

PRM showed a statistical difference between pCR response groups (P < 0.01) and AUC of 0.88 for the prediction of non-pCR. Logistic regression analysis demonstrated that PRMdce+ and Grade II were significant (P < 0.01) for non-pCR prediction (AUC = 0.94). Peripheral tumor region demonstrated higher performance for the prediction of non-pCR (AUC = 0.85) than intermediate and central zones; however, statistical comparison showed no significant difference.

DATA CONCLUSION

PRM could be predictive of non-pCR 24-72 hours after initiation of chemotherapy treatment. Moreover, the peripheral region showed increased AUC for non-pCR prediction and increased signal intensity during treatment for non-pCR tumors, information that could be used for optimal tissue sampling.

LEVEL OF EVIDENCE

1 Technical Efficacy Stage: 4 J. Magn. Reson. Imaging 2020;51:1403-1411.

Hematologic toxicity in BRCA1 and BRCA2 mutation carriers during chemotherapy: A retrospective matched cohort study

Women who inherit a BRCA1 or BRCA2 mutation have an increased risk of breast cancer. Preliminary evidence suggests they may also have defects in bone marrow function. To test this hypothesis, we conducted a multicenter, retrospective, matched cohort study, comparing women with localized breast cancer requiring cytotoxic chemotherapy who carried an inherited BRCA1 or BRCA2 mutation to similar wild‐type patients treated between 1995 and 2017 and matched based on age, race, site, and chemotherapy regimen. The proportion who developed specific hematologic toxicities, timing of these toxicities, and patterns of blood count fluctuations over time were compared among BRCA1 carriers vs matched wild‐type patients and among BRCA2 carriers vs matched wild‐type patients. 88 BRCA1 carriers and 75 BRCA2 carriers were matched to 226 and 242 wild‐type patients, respectively. The proportions and timing of experiencing any grade or grade 3/4 cytopenias during chemotherapy were not significantly different for BRCA1 carriers or BRCA2 carriers vs matched wild‐type patients. Proportions requiring treatment modifications and time to first modification were also similar. Patterns of blood count fluctuations over time in mutation carriers mirrored those in wild‐type patients overall and by the most common regimens. Women with an inherited mutation in BRCA1 or BRCA2 experience similar frequency, severity, and timing of hematologic toxicities during curative intent breast cancer chemotherapy as matched wild‐type patients. Our findings suggest that BRCA1 or BRCA2 haploinsufficiency is sufficient for adequate bone marrow reserve in the face of short‐term repetitive hematopoietic stressors.

Incidence of Hypersensitivity Reactions to Carboplatin or Paclitaxel in Patients With Ovarian, Fallopian Tube, or Primary Peritoneal Cancer With or Without BRCA1 or BRCA2 Mutations

The association of BRCA mutation status with hypersensitivity reactions (HSRs) to carboplatin has gained interest in recent years, particularly in patients with ovarian, fallopian tube, and primary peritoneal cancer. The primary objective of this study is to determine whether the presence of BRCA mutations increased the likelihood of HSRs to carboplatin. The incidence of HSRs to paclitaxel and symptom grade based on the Common Terminology Criteria for Adverse Events, version 4.0, were explored as secondary endpoints. A retrospective chart review of patients with ovarian, fallopian tube, or primary peritoneal cancer at the University of Arizona Cancer Center who underwent treatment with carboplatin-containing regimens and received genetic testing was performed. Institutional review board approval was obtained for this study. Fisher's exact test was used to analyze the primary outcome. Out of 167 initial patients, 62 with germline test results constituted the evaluable sample. 15 of 62 (24.2%) BRCA-tested patients were treated with carboplatin monotherapy, while 44 of 62 (71.0%) patients were treated with paclitaxel-containing regimens. Hypersensitivity reactions occurred in 4 of 13 (30.8%) BRCA-mutated patients and 22 of 49 (44.9%) BRCA wild-type patients (p = .5291). Hypersensitivity reactions to paclitaxel occurred in 1 of 13 (7.7%) BRCA-mutated patients and 26 of 49 (53.1%) BRCA wild-type patients (p = .0039). Overall, there were 11 grade 1 reactions, 14 grade 2 reactions, and 16 grade 3 reactions to carboplatin. All reactions to carboplatin in BRCA-mutated patients were grade 1. All paclitaxel reactions manifested as grade 2. The sample size was the main study limitation. The presence of BRCA mutations was not statistically significantly associated with a higher incidence of HSRs to carboplatin, but was statistically significant with regards to paclitaxel.

BRCA1/BRCA2 germline mutations and chemotherapy-related hematological toxicity in breast cancer patients

PURPOSE

BRCA1 and BRCA2 proteins are central to DNA repair process through homologous recombination. We hypothesize that BRCA1/BRCA2 mutation carriers may exhibit increased hematological toxicity when receiving genotoxic chemotherapy.

METHODS

We included women with primary breast cancers screened for BRCA1/BRCA2 germline mutations and treated with (neo)adjuvant chemotherapy in Geneva (Swiss cohort). The primary endpoint was the incidence of febrile neutropenia following the first chemotherapy cycle (C1). Secondary endpoints were the incidence of grade 3-4 neutropenia, grade 4 neutropenia and hospitalization during C1, G-CSF use and chemotherapy dose reduction during the entire chemotherapy regimen. Long-term toxicities (hematological, cardiac and neuropathy) were assessed in the Swiss cohort and a second cohort of patients from Lyon (French cohort).

RESULTS

Overall, 221 patients were assessed for acute hematological toxicity, including 23 BRCA1 and 22 BRCA2 carriers. Following the C1, febrile neutropenia had an incidence of 35% (p = 0.002), 14% (p = 0.562) and 10% among BRCA1, BRCA2 and non-carriers, respectively. Grade 4 neutropenia was found in 57% of BRCA1 (p < 0.001), 14% of BRCA2 (p = 0.861) and 18% of non-carriers. G-CSF support was necessary in 86% of BRCA1 (p = 0.005), 64% of BRCA2 (p = 0.285) and 51% of non-carriers. For long-term toxicity analysis, 898 patients were included (167 BRCA1-, 91 BRCA2- and 640 non-carriers). There was no difference between the 3 groups.

CONCLUSIONS

BRCA1 germline mutations is associated with greater acute hematological toxicity in breast cancer patients. These observations could have implication for primary prophylaxis with G-CSF.

BRCA Mutation Status Is Not Associated With Increased Hematologic Toxicity Among Patients Undergoing Platinum-Based Chemotherapy for Ovarian Cancer

OBJECTIVE

Women with an inherited BRCA1 or BRCA2 mutation may have an impaired ability to repair chemotherapy-induced damage as a result of a state of haploinsufficiency and may experience greater treatment-related toxicity. The objective of this study was to compare the hematologic adverse effect profiles associated with platinum-based chemotherapy in ovarian cancer patients with and without germline BRCA mutations.

METHODS

We conducted a retrospective analysis of patients treated for high-grade serous ovarian cancer at Princess Margaret Cancer Center, Toronto, Ontario between January 2000 and December 2015. We included only women with known BRCA mutation status and who received first-line platinum-based chemotherapy. We compared 3 primary measures of myelosuppression (ie, hemoglobin levels, platelet counts, and neutrophil counts) before each cycle of chemotherapy in patients with and without a BRCA mutation.

RESULTS

We included 130 BRCA mutation carriers and 302 noncarriers who met the eligibility criteria. There were no significant differences in baseline hemoglobin levels, neutrophil counts, or platelet counts between the groups (P ≥ 0.31). We found no significant difference in 3 measures of hematologic toxicity (ie, neutropenia, anemia, or thrombocytopenia) based on BRCA mutation status across all chemotherapy cycles (P ≥ 0.06). Although BRCA mutation carriers were more likely to experience an absolute neutrophil count below 1.0 × 10/L than noncarriers (P = 0.02), this did not translate to an increased frequency of dose reduction or dose delay.

DISCUSSION

Among women with ovarian cancer, hematologic toxicity does not appear to be more frequent in BRCA mutation carriers than in noncarriers. This is reassuring for clinicians treating ovarian cancer patients with respect to dosing regimens. These findings do not support the hypothesis that a haploinsufficiency phenotype exists with respect to the repair of chemotherapy-induced double-strand DNA breaks in this high-risk population.

Total choline quantification measured by 1H MR spectroscopy as early predictor of response after neoadjuvant treatment for locally advanced breast cancer: The impact of immunohistochemical status

BACKGROUND

Validation of new biomarkers is essential for the early evaluation of neoadjuvant treatments.

PURPOSE

To determine whether measurements of total choline (tCho) by 1H spectroscopy could predict morphological or pathological complete response (pCR) of neoadjuvant treatment and whether breast cancer subgroups are related to prediction accuracy.

STUDY TYPE

Prospective, nonrandomized, monocentric, diagnostic study.

POPULATION

Sixty patients were initially included with 39 women participating in the final cohort.

FIELD STRENGTH/SEQUENCE

A 1.5T scanner was used for acquisition and MRS was performed using the syngo GRACE sequence.

ASSESSMENT

MRS and MRI examinations were performed at baseline (TP1), 24-72 hours after first chemotherapy (TP2), after the end of anthracycline treatment (TP3), and MRI only after the end of taxane treatment (TP4). Early (EMR) and late (LMR) morphological response were defined as %ΔDmax13 or %ΔDmax14, respectively. Responders were patients with %ΔDmax >30. Pathological complete response (pCR) patients achieved a residual cancer burden score of 0.

STATISTICAL TESTS

T-test, receiver operating characteristic (ROC) curves, multiple regression, logistic regression, one-way analysis of variance (ANOVA) analysis were used for the analysis.

RESULTS

At TP1 there was a significant difference between response groups for tCho1 concerning EMR prediction (P = 0.05) and pCR (P < 0.05) and for K_ep 1 (P = 0.03) concerning LMR prediction. At TP2, no modification of tCho and other parameters could predict response. At TP3, ΔtCho, ΔDmax, and ΔVol could predict LMR (P < 0.05 for all parameters), pCR (P < 0.05 for all parameters), and ΔK^trans could predict only pCR (P = 0.04). Logistic regression at baseline showed the highest area under the curve (AUC) of 0.9 for prediction of pCR. The triple negative (TN) subgroup showed significantly higher tCho at baseline (P = 0.02) and higher ΔtCho levels at TP3 (P < 0.05).

DATA CONCLUSION

Baseline measurements of tCho in combination with clinicopathological criteria could predict non-pCR with a high AUC. Furthermore, tCho quantification for prediction of pCR was more sensitive for TN tumors.

LEVEL OF EVIDENCE

1 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2018;48:982-993.

Differential Toxicity in Patients with and without DNA Repair Mutations: Phase I Study of Carboplatin and Talazoparib in Advanced Solid Tumors

Purpose: The PARP inhibitor (PARPi) talazoparib may potentiate activity of chemotherapy and toxicity in cells vulnerable to DNA damage.Experimental Design: This phase I study evaluated the safety, tolerability, pharmacokinetics, and efficacy of talazoparib and carboplatin. Pharmacokinetic modeling explored associations between DNA vulnerability and hematologic toxicity.Results: Twenty-four patients (eight males; 16 females) with solid tumors were enrolled in four cohorts at 0.75 and 1 mg daily talazoparib and weekly carboplatin (AUC 1 and 1.5, every 2 weeks or every 3 weeks), including 14 patients (58%) with prior platinum treatment. Dose-limiting toxicities included grade 3 fatigue and grade 4 thrombocytopenia; the MTD was not reached. Grade 3/4 toxicities included fatigue (13%), neutropenia (63%), thrombocytopenia (29%), and anemia (38%). After cycle 2's dose, delays/reductions were required in all patients. One complete and two partial responses occurred in germline BRCA1/2 (gBRCA1/2) patients. Four patients showed stable disease beyond 4 months, three of which had known mutations in DNA repair pathways. Pharmacokinetic toxicity modeling suggests that after three cycles of carboplatin AUC 1.5 every 3 weeks and talazoparib 1 mg daily, neutrophil counts decreased 78% [confidence interval (CI), 87-68] from baseline in gBRCA carriers and 63% (CI, 72-55) in noncarriers (P < 0.001). Pharmacokinetic toxicity modeling suggests an intermittent, pulse dosing schedule of PARP inhibition, differentiated by gBRCA mutation status, may improve the benefit/risk ratio of combination therapy.Conclusions: Carboplatin and talazoparib showed efficacy in DNA damage mutation carriers, but hematologic toxicity was more pronounced in gBRCA carriers. Carboplatin is best combined with intermittent talazoparib dosing differentiated by germline and somatic DNA damage mutation carriers. Clin Cancer Res; 23(21); 6400-10. ©2017 AACR.

Cytotoxic and targeted therapy for hereditary cancers

There is a number of drugs demonstrating specific activity towards hereditary cancers. For example, tumors in BRCA1/2 mutation carriers usually arise via somatic inactivation of the remaining BRCA allele, which makes them particularly sensitive to platinum-based drugs, PARP inhibitors (PARPi), mitomycin C, liposomal doxorubicin, etc. There are several molecular assays for BRCA-ness, which permit to reveal BRCA-like phenocopies among sporadic tumors and thus extend clinical indications for the use of BRCA-specific therapies. Retrospective data on high-dose chemotherapy deserve consideration given some unexpected instances of cure from metastatic disease among BRCA1/2-mutated patients. Hereditary non-polyposis colorectal cancer (HNPCC) is characterized by high-level microsatellite instability (MSI-H), increased antigenicity and elevated expression of immunosuppressive molecules. Recent clinical trial demonstrated tumor responses in HNPCC patients treated by the immune checkpoint inhibitor pembrolizumab. There are successful clinical trials on the use of novel targeted agents for the treatment or rare cancer syndromes, e.g. RET inhibitors for hereditary medullary thyroid cancer, mTOR inhibitors for tumors arising in patients with tuberous sclerosis (TSC), and SMO inhibitors for basal-cell nevus syndrome. Germ-line mutation tests will be increasingly used in the future for the choice of the optimal therapy, therefore turnaround time for these laboratory procedures needs to be significantly reduced to ensure proper treatment planning.