Comparative Genomics Reveals Distinct Immune-oncologic Pathways in African American Men with Prostate Cancer.

PURPOSE: The role of immune-oncologic mechanisms of racial disparities in prostate cancer remains understudied. Limited research exists to evaluate the molecular underpinnings of immune differences in African American men (AAM) and European American men (EAM) prostate tumor microenvironment (TME). EXPERIMENTAL DESIGN: A total of 1,173 radiation-naïve radical prostatectomy samples with whole transcriptome data from the Decipher GRID registry were used. Transcriptomic expressions of 1,260 immune-specific genes were selected to assess immune-oncologic differences between AAM and EAM prostate tumors. Race-specific differential expression of genes was assessed using a rank test, and intergene correlational matrix and gene set enrichment was used for pathway analysis. RESULTS: AAM prostate tumors have significant enrichment of major immune-oncologic pathways, including proinflammatory cytokines, IFNα, IFNγ, TNFα signaling, ILs, and epithelial-mesenchymal transition. AAM TME has higher total immune content score (ICSHIGH) compared with 0 (37.8% vs. 21.9%, P = 0.003). AAM tumors also have lower DNA damage repair and are genomically radiosensitive as compared with EAM. IFITM3 (IFN-inducible transmembrane protein 3) was one of the major proinflammatory genes overexpressed in AAM that predicted increased risk of biochemical recurrence selectively for AAM in both discovery [HRAAM = 2.30; 95% confidence interval (CI), 1.21-4.34; P = 0.01] and validation (HRAAM = 2.42; 95% CI, 1.52-3.86; P = 0.0001) but not in EAM. CONCLUSIONS: Prostate tumors of AAM manifest a unique immune repertoire and have significant enrichment of proinflammatory immune pathways that are associated with poorer outcomes. Observed immune-oncologic differences can aid in a genomically adaptive approach to treating prostate cancer in AAM.

CDK 4/6 inhibitor palbociclib (PD0332991) in Rb+ advanced breast cancer: phase II activity, safety, and predictive biomarker assessment.

PURPOSE: The G1-S checkpoint of the cell cycle is frequently dysregulated in breast cancer. Palbociclib (PD0332991) is an oral inhibitor of CDK4/6. Based upon preclinical/phase I activity, we performed a phase II, single-arm trial of palbociclib in advanced breast cancer. EXPERIMENTAL DESIGN: Eligible patients had histologically confirmed, metastatic breast cancer positive for retinoblastoma (Rb) protein and measureable disease. Palbociclib was given at 125 mg orally on days 1 to 21 of a 28-day cycle. Primary objectives were tumor response and tolerability. Secondary objectives included progression-free survival (PFS) and assessment of Rb expression/localization, KI-67, p16 loss, and CCND1 amplification. RESULTS: Thirty-seven patients were enrolled; 84% hormone-receptor (HR)(+)/Her2(-), 5% HR(+)/Her2(+), and 11% HR(-)/Her2(-), with a median of 2 prior cytotoxic regimens. Two patients had partial response (PR) and 5 had stable disease ≥ 6 months for a clinical benefit rate (CBR = PR + 6moSD) of 19% overall, 21% in HR(+), and 29% in HR(+)/Her2(-) who had progressed through ≥2 prior lines of hormonal therapy. Median PFS overall was 3.7 months [95% confidence interval (CI), 1.9-5.1], but significantly longer for those with HR(+) versus HR(-) disease (P = 0.03) and those who had previously progressed through endocrine therapy for advanced disease (P = 0.02). Grade 3/4 toxicities included neutropenia (51%), anemia (5%), and thrombocytopenia (22%). Twenty-four percent had treatment interruption and 51% had dose reduction, all for cytopenias. No biomarker identified a sensitive tumor population. CONCLUSIONS: Single-agent palbociclib is well tolerated and active in patients with endocrine-resistant, HR(+), Rb-positive breast cancer. Cytopenias were uncomplicated and easily managed with dose reduction.

Feasibility of using tissue microarrays for the assessment of HER-2 gene amplification by fluorescence in situ hybridization in breast carcinoma.

Tissue microarrays (TMAs) have been commonly used to study protein expression by immunohistochemistry (IHC). However, limited data exist on the validity of using TMAs to study gene amplification. In this study, we evaluated the feasibility of using breast carcinoma TMAs to study HER-2 gene amplification by fluorescence in situ hybridization (FISH). In addition, hormonal receptor status (ER and PR) and HER-2 protein overexpression by IHC were also studied, and results were compared with whole tissue sections. FISH for HER-2 was performed on formalin-fixed paraffin-embedded tissue from 114 invasive breast carcinomas both on whole tissue sections and on TMAs containing the same tumors. The TMA was created using 0.6-mm tissue cores with four sampled cores per tumor from the same tissue block used for whole section FISH. The PathVysion HER-2 probe kit was used for the FISH analysis. A ratio of HER-2:Chromosome17 > or =2.0 was interpreted as positive for gene amplification. The ER or PR was interpreted as positive when nuclear staining was detected in more than 10% of tumor cells. The HER-2 IHC (HercepTest; DAKO Corp, Carpinteria, CA) results were interpreted as 0, 1+, 2+, and 3+ according to standard criteria. The FISH results in the TMA and whole sections were concordant in 99 out of 101 successfully analyzed cases (99%). The FISH scores were consistent among the two to four cores in the majority of the cases. ER and PR results were concordant between whole sections and TMA cores in 97% (107/110) and 89% (97/109) cases, respectively. The overall concordance for HER-2 status by IHC between whole sections and TMA cores was 86% (94 out of 109 cases). TMAs are a reliable approach to study HER-2 gene amplification in a high throughput manner.

Low-grade myxofibrosarcoma: a clinicopathologic analysis of 49 cases treated at a single institution with simultaneous assessment of the efficacy of 3-tier and 4-tier grading systems.

Grading of myxofibrosarcoma (MFS) is contentious and based on a variety of factors, such as the percentage of myxoid or solid areas, tumor necrosis, mitotic counts, and so on. These factors are often used in combination for different grading schemes, which have not been uniformly evaluated by consistent criteria for patients treated and prospectively followed up at a single institution. Because only a subset of low-grade (LG) MFS will progress to high grade and metastasize after relentless local recurrences, we analyze various histologic parameters and grading methods to identify prognostic predictors of the LGMFS. Forty-nine cases were classified as LGMFS after review, by using > or =30% of myxoid component, but < or =20% of solid areas and only focal, < or =10%, of tumor necrosis as cutoffs, as modified from a 2-tier system that is used in our hospital. These cases were also graded in parallel by French Federation of Cancer Centers Sarcoma Group (FNCLCC) 3-tier and 4-tier grading schemes. The study cohort consisted of 26 men and 23 women, with a median age of 60.5 years. Nineteen cases were superficial, and 30 were deep seated, with the most common site being the lower limb (57%), followed by the upper limb (31%), trunk (8%), and head and neck (4%). The primary tumors ranged from 1.5 to 24 cm in size. Solid areas (5% to 20%) were seen in 23 cases, tumor necrosis (5% to 10%) was observed in 4 cases, and a predominant myxoid area (> or =75%) was noted in 22 cases. Mitotic activity ranged from 0 to 16 (median, 2) per 10 HPF. Comparing FNCLCC 3-tier versus 4-tier grading, respectively, 26 versus 10 tumors were classified as grade I, and 23 versus 39, as grade II, with 16 cases (33%) graded discordantly by 2 schemes. A median follow-up of 55 months in 49 patients (range, 9 to 171 months) revealed local recurrence occurring in 28 patients (57%), 15 and 7 of which developed multiple local recurrences and distant metastases, respectively. There was only 1 case with pulmonary metastasis without a prior local recurrence. Currently, 33 patients are alive with no evidence of disease, 4 are alive with disease, 9 are dead of disease, and 3 are dead of unknown causes. The 5-year recurrence-free survival, metastasis-free survival (MeFS), and disease-specific mortality (DSM) rates were 41%, 90%, and 4.4%, respectively. Size of larger than 5 cm (P = 0.032), tumor necrosis (P = 0.033), and < 75% of myxoid area (P = 0.042) were significant risk factors for DSM; the former two (P = 0.011 for size larger than 5 cm, P = 0.038 for necrosis) were also significantly related to MeFS. Both FNCLCC 3-tier and 4-tier schemes failed to show a significantly better outcome in grade I LGMFS than grade II lesions with respect to all 3 endpoints. In conclusion, our data statistically validated the previous impression that even the blandest LGMFS still carries a recurrent potential that cannot be foreseen by either different grading schemes or other clinicopathologic parameters. However, DSM rate is significantly related to tumor necrosis, large size, and decreased myxoid area. Tumors having necrosis or exceeding 5 cm are at significant risk of metastatic relapse.