Ixazomib, Oral Metronomic Cyclophosphamide, and Dexamethasone for First-Line Treatment of Multiple Myeloma: A Phase II Brown University Oncology Group Study.

BACKGROUND: Newly diagnosed multiple myeloma patients have many available treatment options. While lenalidomide, bortezomib, and dexamethasone (RVD) is the preferred initial treatment for many patients, several other agents may provide similar efficacy with less toxicity and improved ease of administration. METHODS: We evaluated the safety and efficacy of the all-oral regimen of ixazomib, cyclophosphamide, and dexamethasone with the use of metronomic cyclophosphamide dosing in the treatment of patients with newly diagnosed multiple myeloma. RESULTS: The study was stopped prior to planned enrollment due to slow recruitment, with 12 patients available for final analysis. The overall response rate was 58.3% with 2 patients achieving a very good partial response (16.7%) and 5 patients achieving a partial response (41.7%). Median progression-free survival was 16 months, and median overall survival was 43 months. There were no episodes of grade 3 or greater peripheral neuropathy. Grade 3 or greater dermatologic toxicity was experienced in 50% of patients. CONCLUSION: Although limited enrollment prevented full efficacy evaluation, our data do not support further study of metronomic cyclophosphamide in combination with ixazomib and dexamethasone in the treatment of newly diagnosed multiple myeloma. The activity of this regimen in the relapsed/refractory setting requires further study (ClinicalTrials.gov Identifier: NCT02412228).

Stromal ColXα1 expression correlates with tumor-infiltrating lymphocytes and predicts adjuvant therapy outcome in ER-positive/HER2-positive breast cancer.

BACKGROUND: The breast cancer microenvironment contributes to tumor progression and response to chemotherapy. Previously, we reported that increased stromal Type X collagen α1 (ColXα1) and low TILs correlated with poor pathologic response to neoadjuvant therapy in estrogen receptor and HER2-positive (ER+/HER2+) breast cancer. Here, we investigate the relationship of ColXα1 and long-term outcome of ER+/HER2+ breast cancer patients in an adjuvant setting. METHODS: A total of 164 cases with at least 5-year follow-up were included. Immunohistochemistry for ColXα1 was performed on whole tumor sections. Associations between ColXα1expression, clinical pathological features, and outcomes were analyzed. RESULTS: ColXα1 expression was directly proportional to the amount of tumor associated stroma (p = 0.024) and inversely proportional to TILs. Increased ColXα1 was significantly associated with shorter disease free survival and overall survival by univariate analysis. In multivariate analysis, OS was lower in ColXα1 expressing (HR = 2.1; 95% CI = 1.2-3.9) tumors of older patients (> = 58 years) (HR = 5.3; 95% CI = 1.7-17) with higher stage (HR = 2.6; 95% CI = 1.3-5.2). Similarly, DFS was lower in ColXα1 expressing (HR = 1.8; 95% CI = 1.6-5.7) tumors of older patients (HR = 3.2; 95% CI = 1.3-7.8) with higher stage (HR = 2.7; 95% CI = 1.6-5.7) and low TILs. In low PR+ tumors, higher ColXα1 expression was associated with poorer prognosis. CONCLUSION: ColXα1 expression is associated with poor disease free survival and overall survival in ER+/HER2+ breast cancer. This study provides further support for the prognostic utility of ColXα1 as a breast cancer associated stromal factor that predicts response to chemotherapy.

Stem cell phenotype predicts therapeutic response in glioblastomas with MGMT promoter methylation.

A growing body of evidence supports the presence of a population of cells in glioblastoma (GBM) with a stem cell-like phenotype which shares certain biological markers with adult neural stem cells, including expression of SOX2, CD133 (PROM1), and NES (nestin). This study was designed to determine the relationship between the expression of these stem cell markers and the clinical outcome in GBM patients. We quantified the intensity of expression of the proteins CD133 and SOX2 by immunohistochemistry (IHC) in a cohort of 86 patients with IDH-wildtype GBM, and evaluated patient outcomes using Kaplan-Meier and Cox proportional hazards analysis. In our patients, MGMT promoter methylation status and age were predictors of overall survival and progression free survival. The levels of SOX2 and CD133 were not associated with outcome in univariate analysis; however, stratification of tumors based on low or high levels of CD133 or SOX2 expression revealed that MGMT methylation was a predictor of progression-free survival and overall survival only for tumors with high levels of expression of CD133 or SOX2. Tumors with low levels of expression of CD133 or SOX2 did not show any relationship between MGMT methylation and survival. This relationship between MGMT and stem cell markers was confirmed in a second patient cohort, the TCGA dataset. Our results show that stratification of GBM by the level of expression of CD133 and SOX2 improved the prognostic power of MGMT promoter methylation status, identifying a low-expressing group in which the clinical outcome is not associated with MGMT promoter methylation status, and a high-expressing group in which the outcome was strongly associated with MGMT promoter methylation status. These findings support the concept that the presence of a high stem cell phenotype in GBM, as marked by expression of SOX2 or CD133, may be associated with the clinical response to treatment.

The Brown University Oncology Group Experience With FOLFOX + Nab-paclitaxel [FOLFOX-A] for Metastatic and Locally Advanced Pancreatic, BrUOG-292 and BrUOG-318.

OBJECTIVES: To evaluate response rate, toxicity, and efficacy of the novel combination of nab-paclitaxel, oxaliplatin, 5-fluorouracil, and leucovorin [FOLFOX-A] in patients with advanced pancreatic ductal adenocarcinoma [PDAC]. METHODS: BrUOG-292 and BrUOG-318 were two concurrently run, prospective, single-arm phase II studies evaluating FOLFOX-A as first-line therapy in patients with metastatic and locally advanced/borderline resectable PDAC respectively. The FOLFOX-A regimen consisted of 5-fluorouracil, 1200 mg/m 2 /d as a continuous intravenous (IV) infusion over 46 hours, leucovorin 400 mg/m 2 IV, oxaliplatin 85 mg/m 2 IV, and nab-paclitaxel 150 mg/m 2 IV on day 1 every 14 days up to a maximum of 12 cycles. Patients with locally advanced or borderline resectable disease were permitted to stop treatment after 6 cycles and receive radiation therapy and/or surgical exploration if feasible. The primary end point was overall response rate [ORR]. Secondary end points were median progression-free survival [PFS], median overall survival [OS], and safety. RESULTS: Seventy-eight patients with previously untreated PDAC were enrolled between June 2014 and November 2019; 76 patients were evaluable. The median follow-up was 40 months and 32 months, respectively. overall response rate was 34%. Among the patients enrolled on BrUOG-292 [48 patients], the PFS was 5 months and OS was 11 months, respectively. For those enrolled on BrUOG 318 [28 patients], the PFS was 11 months and OS was 22 months. Treatment-related toxicities included grade 3 fatigue [40%], diarrhea [14%], and neuropathy [2%]. CONCLUSIONS: The combination of FOLFOX-A has promising activity in PDAC and may represent an alternative to FOLFIRINOX when reduction of gastrointestinal toxicity is required.

Nanoliposomal Irinotecan and Metronomic Temozolomide for Patients With Recurrent Glioblastoma: BrUOG329, A Phase I Brown University Oncology Research Group Trial.

BACKGROUND: Liposomal formulations may improve the solubility and bioavailability of drugs potentially increasing their ability to cross the blood-brain barrier. We performed a phase I study to determine the maximum tolerated dose and preliminary efficacy of pegylated nanoliposomal irinotecan (nal-IRI)+metronomic temozolomide (TMZ) in patients with recurrent glioblastoma. PATIENTS AND METHODS: Patients with glioblastoma who progressed after at least 1 line of therapy were eligible. All patients received TMZ 50 mg/m2/d until disease progression. Three dose levels of nal-IRI were planned, 50, 70, and 80 mg/m2, intravenously every 2 weeks. Patients were accrued in a 3+3 design. The study included a preliminary assessment after the first 13 evaluable patients. The trial would be terminated early if 0 or 1 responses were observed in these patients. RESULTS: Twelve patients were treated over 2 dose levels (nal-IRI 50 and 70 mg/m2). At dose level 2, nal-IRI 70 mg/m2, 2 of 3 patients developed dose-limiting toxicities including 1 patient who developed grade 4 neutropenia and grade 3 diarrhea and anorexia and 1 patient with grade 3 diarrhea, hypokalemia fatigue, and anorexia. Accrual to dose level 1 was expanded to 9 patients. The Drug Safety Monitoring Board (DSMB) reviewed the data of the initial 12 patients-there were 0/12 responses (0%) and the median progression-free survival was 2 months and accrual was halted. CONCLUSIONS: The maximum tolerated dose of nal-IRI was 50 mg/m2 every 2 weeks with TMZ 50 mg/m2/d. The dose-limiting toxicities were diarrhea and neutropenia. No activity was seen at interim analysis and the study was terminated.

Adjuvant FOLFOX+Nab-Paclitaxel (FOLFOX-A) for Pancreatic Cancer: A Brown University Oncology Research Group Phase II Study (BrUOG295).

OBJECTIVES: Multiple clinical trials have established a role for adjuvant chemotherapy for patients with pancreatic ductal adenocarcinoma. Adjuvant FOLFIRINOX increases survival as compared with gemcitabine but with increased toxicity. FOLFOX+nab-paclitaxel (FOLFOX-A) was developed by the Brown University Oncology Research Group (BrUOG) as an alternative to FOLFIRINOX. This phase II trial explored the feasibility and toxicity of adjuvant FOLFOX-A in patients who have completed resection for pancreatic ductal adenocarcinoma. PATIENTS AND METHODS: Patients with resected pancreatic ductal adenocarcinoma were eligible. The primary objective was to determine the feasibility of adjuvant FOLFOX-A. Patients experiencing grade 2 neuropathy received a 20% reduction of oxaliplatin. Secondary end points were disease-free survival, and overall survival. RESULTS: Between June 2014 and October 2018, 25 patients were enrolled following surgical resection. The median number of cycles completed was 9.5. Median disease-free survival was 19.7 months (95% confidence interval, 10.3 to not reached) and median overall survival was 53.5 months (95% confidence interval, 24.2 to not reached). The most common treatment-related grade 3 or greater adverse events were fatigue (58%), nausea (13%), and neutropenia (26%). Fourteen patients had grade 2 neuropathy (58%) and 1 patient (4%) had grade 3 neuropathy. Only 2 patients (8%) had grade 3 diarrhea. CONCLUSIONS: Adjuvant FOLFOX-A is a feasible multi-agent adjuvant treatment regimen and, with further validation, could be an alternative to FOLFIRINOX.

Loss of Expression of a Novel Chromatin Remodeler SMARCA1 in Soft Tissue Sarcoma.

INTRODUCTION: Vital cellular processes such as proliferation and differentiation are regulated by chromatin remodeling complexes. A variety of neoplasms have been discovered to have genomic alterations (GAs) and loss of immunohistochemical (IHC) expression of chromatin remodelers ARID1A (BAF250A), SMARCA2 (BRM), SMARCA4 (BRG1), and SMARCB1 (INI1). SMARCA1 (SNF2L) is another member of the chromatin remodelers, and has not yet been studied in neoplasia. As SMARCA1 is located on chromosome X, could be potentially inactivated by a single hit. We aimed to evaluate GAs and protein expression of SMARCA1 in soft tissue tumors. METHOD: The publically available cBioPortal.32e34 platform was queried to analyze data on soft tissue tumors from The Cancer Genome Atlas project (TCGA) related to SMARCA1 GAs. Our institutional archives were queried to collect 26 cases of soft tissue tumors including 10 undifferentiated sarcomas, 5 leiomyosarcomas, 6 liposarcomas, and 5 malignant peripheral sheath tumors (MPNST). IHC for SMARCA1 with an SNF 2C4 monoclonal antibody was performed on whole tissue sections. RESULTS: SMARCA1 GAs were present in 8/261 soft tissue sarcomas (3%) in the TCGA dataset. Leiomyosarcomas had most common SMARCA1 GAs in 6/99 cases. SMARCA1 deletions existed in 1/56 dedifferentiated liposarcomas and 1/48 undifferentiated sarcomas. No SMARCA1 GAs occurred in other sarcoma subtypes. SMARCA1 IHC was studied in the sarcoma subtypes with potential SMARCA1 alterations in our institutional cases. SMARCA1 nuclear expression was lost in 3/10 cases (30%) of undifferentiated sarcoma, and 2/5 cases of MPNST (40%). SMARCA1 expression was intact in all cases of leiomyosarcoma and liposarcoma. CONCLUSION: This is the first study to demonstrate loss of expression of SMARCA1 in soft tissue sarcomas subtypes, including undifferentiated sarcoma. Our study highlights merit for further investigation on the role of SMARCA1 in the differentiation process and molecular mechanisms of SMARCA1 inactivation.

Differentiating breast carcinoma with signet ring features from gastrointestinal signet ring carcinoma: assessment of immunohistochemical markers.

Signet ring morphology is recognized throughout the gastrointestinal tract. However, this pattern may be observed in other primary sites giving rise to diagnostic challenges in the work-up of metastases. Relatively newer immunohistochemical markers have not been evaluated in this context. We assessed expression patterns of several common immunohistochemical markers in tumors with Signet ring morphology to delineate a pragmatic approach to this differential diagnosis. Primary breast and gastrointestinal carcinomas showing Signet ring features were reviewed. Non-mammary and non-gastrointestinal tumors with this morphology were included for comparison. Estrogen receptor (ER), progesterone receptor (PR), E-cadherin, CK7, CK20, GCDFP-15, mammaglobin, CDX2, GATA-3, and HepPar-1 immunohistochemistry was performed. Expression patterns were compared between breast and gastrointestinal tumors as well as lobular breast and gastric tumors. Ninety-three cases were identified: 33 breast carcinomas including 13 lobular, 50 gastrointestinal tumors including 23 gastric, and 10 from other sites. ER (sensitivity=81.8%, specificity=100%, positive predictive value (PPV)=100%, negative predictive value (NPV)=89.3%) and GATA-3 (sensitivity=100%, specificity=98%, PPV=96.8%, NPV=100%) expression were associated with breast origin. CK20 (sensitivity=66.7%, specificity=93.3%, PPV=94.1%, NPV=63.6%) and CDX2 (sensitivity=72%, specificity=100%, PPV=100%, NPV=68.9%) demonstrated the strongest discriminatory value for gastrointestinal origin. These markers exhibited similar discriminatory characteristics when comparing lobular and gastric signet ring carcinomas. In a limited trial on metastatic breast and gastric cases, these markers successfully discriminated between breast and gastric primary sites in 15 of 16 cases. ER and GATA-3 are most supportive of mammary origin and constitute an effective panel for distinguishing primary breast from primary gastrointestinal Signet ring tumors when combined with CK20 and CDX2 immunohistochemistry.