Defining transcriptomic profiles of early-stage mucinous breast cancers: A FLEX sub study

3134

Background: Mucinous breast cancer (MuBC) is a rare subtype of invasive ductal carcinoma (IDC) that accounts for less than 2% of all breast cancers and is associated with a favorable prognosis. Since MuBCs are rare in clinical trials, current treatment guidelines are extrapolated from IDC-no special type (IDC-NST). To provide better understanding of MuBCs and factors contributing to their clinical behavior, we examined the transcriptomic profiles of MuBCs in our FLEX study. Methods: The prospective, observational FLEX Study (NCT03053193) includes stage I-III breast cancer patients who receive MammaPrint (MP)/BluePrint (BP) testing and consent to full transcriptome and clinical data collection. For this study, histologically confirmed MuBCs (n = 102) in the FLEX database were included. All patients examined were ER+/HER2- by immunohistochemistry and Luminal by BP. MuBC was compared with IDC matched for Age, MP, and BP index (n = 97). Differential gene expression analyses (DGEA) were performed with R package ‘limma’ and differentially expressed genes (DEGs) were considered significant if they had an adjusted p < 0.05 and fold change ≥ 2. Results: DGEA comparing MuBC (n = 102) with IDC (n = 97) revealed 60 DEGs, regardless of the genomic risk, of which 42 genes were upregulated and 18 were downregulated in MuBC relative to IDC. Genes associated with MuBC, such as MUC2, TFF1, CARTPT were among the upregulated genes. Of the 102 MuBC patients, 56 were Luminal A (MP Low Risk-LR) and 46 were Luminal B (MP High Risk-HR) by MammaPrint and BluePrint. Comparison of LR MuBC with LR IDC revealed 111 DEGs. Functional enrichment showed upregulation of pathways involved in estrogen response (early & late) and androgen response and a downregulation of the epithelial to mesenchymal transition (EMT) and E2F pathways in LR MuBC compared to LR IDC. DGEA between HR MuBC and HR IDC revealed only 22 DEGs with immune pathways being downregulated in HR MuBC. DGEA comparing LR MuBC with HR MuBC resulted in 63 DEGs, indicating LR and HR MuBC are biologically distinct types. Interestingly in LR MuBC, the tumor suppressor marker SCUBE2 is upregulated. Over expression of SCUBE2 is associated with better prognosis. Conclusions: Although MuBCs are often expected to have low clinical risk, MP revealed that half of the MuBCs examined in this study were MP High Risk (Luminal B). MP low risk MuBC is biologically different from MP low risk IDC, and downregulation of E2F and EMT pathways might lead to favorable prognoses in MP low risk MuBC. MP high risk MuBC showed limited DEGs compared to high-risk IDCs indicating these tumor types are highly genomically similar and likely to benefit from chemotherapy. The downregulation of immune pathways in MP high risk MuBC may lead to immune surveillance escape resulting in metastasis and further investigation is needed. Clinical trial information: NCT03053193.

Investigation of a genomic signature for transcription factor MAF gene amplification and lack of bisphosphonate benefit in early breast cancer

559

Background: MAF amplification has been associated with increased bone metastases in breast cancer (BC). On the contrary, patients without MAF amplification in the primary tumor are more likely to benefit from adjuvant bisphosphonates as shown in a retrospective analysis of the AZURE trial and confirmed with a subset of NSABP-B34 specimens. A genomic signature could identify patients that lack MAF amplification as candidates for adjuvant bisphosphonates. Here we investigated the genes that could predict MAF amplification status. As MAF amplification is associated with high risk of bone metastases, 70-gene risk of distant recurrence signature (MammaPrint/MP) and 80-gene molecular subtyping signature (BluePrint/BP) were used to stratify the patient groups. Methods: A total of 166 BC patients from the UPMC were included in this pilot cohort. Fluorescence in situ hybridization was performed to detect MAF copy number. Signal-to-nucleus ratio (SNR) of ≥2.5 was used as the MAF-amplified (MAF+) cut-off. Differential gene expression analysis was performed with R limma using whole genome microarray data. MAF+ and MAF- (SNR<2.5) were compared within all patients and within patients matched by MP/BP to balance high risk groups. Differentially expressed genes (DEGs) were defined as absolute fold change ≥2 and adjusted p-value <0.05. Prediction of MAF amplification based on gene expression was performed using a correlation-based metric with training set, as well as with 1179 stage I-III BC patients from the FLEX Study (NCT03053193), which includes MP/BP testing and whole transcriptome data collection. Results: Of the 166 patients, 12% were MAF+ and 88% were MAF-. Among the MAF+ patients, 95% were MP High Risk, as expected from the association of MAF amplification and bone metastasis, as opposed to 29% of MAF- patients. Notably, there was no significant correlation between amplification and gene expression of MAF, which emphasizes the importance of utilizing other genes to predict MAF amplification. Comparing whole transcriptome of MAF+ and MAF- patients, 48 DEGs were found. From the MP/BP matched comparisons, genes ≥2-fold change were included in the final set of 57 genes, where C-X-C motif chemokine ligand and S100 calcium binding protein encoding genes were enriched. The 57-gene classifier of MAF status yielded 92% accuracy, 94% specificity, and 75% sensitivity on the training set. Interestingly, when the classifier was applied on the FLEX cohort, 12% MAF+ cases were identified, similar to the training set. Conclusions: Whole transcriptome analysis showed that BC tumors with MAF amplification are transcriptionally different than those without. Here we provide a set of 57 genes that could potentially predict MAF amplification status. Future work will expand the dataset and further explore the predictive value of such genomic signature in response to bisphosphonates. Clinical trial information: NCT03053193.

The ImPrint immune signature to identify patients with high-risk early breast cancer who may benefit from PD1 checkpoint inhibition in I-SPY2

514

Background: The remarkable increase of novel Immuno-Oncology drugs in many malignancies has led to the need for biomarkers to identify who would benefit. Various predictive biomarkers have been developed (PD-1/PD-L1 expression, mutations in mismatch repair genes and microsatellite instability, tumor mutational burden and immune infiltration), none have consistently predicted efficacy. The I-SPY2 consortium qualified several expression-based immune biology related signatures that predict response to PD1 checkpoint inhibition. Here we assessed whole transcriptome data of high-risk early-breast cancer (EBC) patients who received Pembrolizumab within the neoadjuvant biomarker-rich I-SPY2 trial (NCT01042379), aiming to migrate the I-SPY2 research findings to a robust clinical grade platform signature to predict sensitivity to PD1 checkpoint inhibition. Methods: Whole transcriptome microarray data were available from pre-treatment biopsies of 69 HER2- patients enrolled in the Pembrolizumab (4 cycles) arm of the I-SPY2 trial. All patients had a High-Risk 70-gene MammaPrint profile. Pathologic complete response (pCR) was defined as no residual invasive cancer in breast or nodes at the time of surgery. Of the 69 patients, 31 had a pCR (12 HR (hormonal receptor)+HER2-, 19 Triple Negative (TN)), while 38 (28 HR+HER2-, 10 TN) had residual disease (RD). To identify the most predictive genes associated with pCR, gene selection was performed comparing pCR and RD groups by iteratively splitting the dataset in training and test, balancing for HR status. Due to limited sample size, leave one out cross validation was used for performance assessment. Genes with effect size > 0.45 were considered significant. Results: A signature of 53 genes, named ImPrint, was identified with overall sensitivity and specificity > 90% and > 80% for predicting pCR to pembrolizumab in all patients. Sensitivity and specificity in TN were > 95% and ≥70%, and in HR+HER2- > 80% and > 85%, respectively. The Positive Predictive Value (PPV) is 77% for the HR+HER2- subgroup. Biological annotation of the 53 genes showed that over 90% of the genes have known immune system related functions, of which 63% were previously known to be involved in immune response (including genes coding PD-L1 and PD-1, as well as those identified in I-SPY2). Conclusions: In the signature development phase, ImPrint predicts pCR to Pembrolizumab in a set of 69 high risk EBC with high sensitivity and specificity. The signature features genes with immune-related functions known to be involved in immune response indicating that it might aid identifying patients with an immune-active phenotype. Importantly, ImPrint appears effective in identifying a subset of HR+HER2- patients who could benefit from immunotherapy. External validation in independent dataset(s) is ongoing and will be presented at the time of the meeting.

Clinical implications for patients with discordant oncotype and MammaPrint results

560

Background: Genomic tests provide critical information regarding risk of recurrence and inform treatment plans by identifying those patients who may safely forgo chemotherapy (CT) or shorten endocrine therapy (ET) duration. The IMPACT trial demonstrated that the 70 -gene risk of recurrence assay MammaPrint (MP) and 80-gene subtyping assay BluePrint (BP) inform treatment planning and increase physician confidence. However, not all genomic tests yield the same results. To examine consistency among genomic tests, we analyzed therapy implications for patients who received results from both MP/BP and Recurrence Score (RS). Methods: Using the FLEX cohort (NCT03053193), we examined 723 patients who received both MP/BP, and RS genomic assays. We assessed the potential clinical impact by examining the standardized reports of RS and MP/BP results. MP classified tumors as either ultralow, low, or high risk and BP further classified them as luminal, basal, or HER2. RS classified tumors as low (RS0-10), intermediate (RS11-25), or high (RS26-100). Clinical impact was defined as discordant genomic resulting in different treatment recommendations. Undertreatment indicates patients who may not have received CT based on RS but may have based on MP/BP and overtreatment those patients who would have received CT based on RS, but not based on MP/BP. ET duration too long is indicative of those patients that are ultralow risk by MP, regardless of RS classification, as those patients may have safely reduced the duration of their ET. Although outcomes are not available, treatment impacts are presuming a patient received both tests, but the treating physician opted to guide therapy according to the RS results rather than MP/BP. Results: We observed discordant results with a clinical impact in 49% (354) of patients, with 34% (244) who may be undertreated, 2% (11) potentially overtreated, and 14% (99) who may not be given the option to decrease ET to two years based on ultralow MP genomic risk. Of 114 concordant High-Risk tumors, 14% (16) were genomically Basal, and likely to require more aggressive CT than typically used in ER+ cancers. The table below summarizes the results. Conclusions: More than half of the patients in this cohort were at potential risk for undertreatment or overtreatment. The risk to patients is far more significant in the event of undertreatment, as this may result in incurable metastatic recurrence. Discordance between RS and MP/BP most often results in potential undertreatment if RS is used for treatment decision-making. Clinical trial information: NCT03053193.

Identification of transcriptional changes with MammaPrint and BluePrint in early-stage breast cancer after neoadjuvant chemotherapy

585

Background: The use of neoadjuvant chemotherapy (NAC) in patients with early-stage breast cancer (EBC) increases the opportunity for genomic testing which can help predict treatment response and optimize outcomes. MammaPrint (MP) classifies tumors as having a Low Risk (LR) or High Risk (HR) of distant recurrence. MP with BluePrint (BP), a molecular subtyping assay, categorize tumors as Luminal A (MP LR), Luminal B (MP HR), HER2, or Basal-Type. Our recent analysis comparing matched pre- and post-NAC tumors found 25% of pre-NAC Luminal B tumors changed to Luminal A post-NAC, which corresponded with improved 5-year outcomes compared with patients who remained Luminal B. Here, we report differential gene expression (DGE) and pathway analyses in these matched tumors that may distinguish the different responses. Methods: Among the patients with EBC who received NAC at Cedars Sinai Medical Center between 2007-2016, 38 with residual disease (RD) had paired pre- and post-NAC tissues. In patients with Luminal tumors, 8 were Luminal B pre- and post-NAC (HR/HR), and 7 were Luminal B pre-NAC but changed to Luminal A post-NAC (HR/LR). Limma R package was used for quantile normalization and DGE analyses. Differentially expressed genes (DEG) with < 0.05 false discovery rate and > 2-fold change were considered significant. Functional pathway enrichment was performed using Metascape. Results: Within HR/LR tumors, a DGE analysis identified 104 DEGs in post-NAC tissues relative to pre-NAC, with changes in cell cycle/proliferation pathways. Interestingly, there was a more robust transcriptional change in HR/HR tumors, with 956 DEGs between post- and pre-NAC samples, with enrichment of extracellular matrix organization, angiogenesis, and wound healing pathways. Notably, immune pathway enrichment was in both HR/LR and HR/HR groups, although the nature of enrichment differed. Immune deconvolution identified significant increases in activated myeloid dendritic cells (DC) and CD8+ T cells in HR/LR but not in HR/HR post-NAC tumors, suggestive of a host immune response. Conclusions: Although post-NAC RD correlates with poor prognosis, even in Luminal tumors, these data suggest gene expression profiling may distinguish a subset with good prognosis. Using matched samples, we assessed the transcriptional differences in tumors that changed MP risk (HR/LR) with tumors that stayed MP HR post-NAC (HR/HR). Overall, HR/HR tumors had a larger transcriptional response with metastatic-related pathway enrichment. Given these patients with HR/HR tumors displayed worse outcomes, pathway changes may indicate resistance and patients may need additional therapy. Differential changes in immune cells between HR/HR and HR/LR tumors were also observed. The activated immune response in HR/LR tumors may be a biomarker for therapy response and improved outcome and will be the focus of further evaluation.

Whole transcriptomic analysis of HR+ breast cancer in Black women classified as basal-type by BluePrint

517

Background: Breast cancer is the leading cause of cancer-associated death among Black women, and they are 41% more likely to die from breast cancer compared to White women. Few studies have evaluated if tumor biology differences contribute to this disparity in outcomes. Similar to triple negative breast cancer (TNBC), hormone receptor-positive (HR+) tumors classified as Basal-Type with BluePrint genomic analysis (HR+/Basal) are more aggressive, higher grade, are over-represented among young Black women and have worse clinical outcomes. TNBC is associated with low ACKR1 expression, which encodes the Duffy antigen and correlates with worse breast cancer outcomes. Given the over-representation and worse outcomes among Black women with HR+/Basal tumors, we compared differentially expressed genes (DEGs) by race and subtype. Methods: This study includes 2657 women with Stage I-III breast cancer who received BluePrint testing and are participants of the ongoing BEST study (5R01CA204819) at Vanderbilt University Medical Center or FLEX study (NCT03053193). Of 455 Black women, 315 had Luminal (HR+/Luminal) and 140 had Basal tumors (66 HR+/Basal and 74 HR-/Basal). White women within FLEX (n = 2202) were included as a reference group with HR+/Luminal (n = 1825), HR+/Basal (n = 158), or HR-/Basal (n = 219) tumors. Two-tailed proportional z-test was used to assess differences in subtype proportion by race. Limma R package was used to perform differential gene expression analysis (DGEA) of whole transcriptome data. Significant DEGs had an adjusted p-value < 0.05 and absolute log2 fold change > 1. Results: Black women had a significantly higher proportion of HR+/Basal (15%; p < 0.001) and HR-/Basal (16%; p < 0.001) tumors compared to White women (7% and 10%, respectively). In a multidimensional scaling analysis, HR+/Basal tumors cluster with TNBC rather than with HR+/Luminal tumors. While a DGEA comparing HR+/Basal with HR+/Luminal tumors resulted in over 700 DEGs within Black women, no DEGs were identified when comparing HR+/Basal tumors with TNBC. ACKR1 expression in HR+/Basal tumors was comparable to TNBC in Black women (p = 0.81) and White women (p = 0.46). In contrast, HR+/Basal tumors had significantly lower ACKR1 expression than HR+/Luminal tumors in Black (p < 0.01) and White women (p < 0.01). Conclusions: In this racially diverse cohort, transcriptomic analyses suggest that HR+/Basal tumors are biologically analogous to TNBC, independent of race. Molecular profiling identified racial disparities in the proportion of HR+/Basal tumors and underscores the need for diverse representation in clinical trials. With an over-representation of HR+/Basal tumors in Black women and evidence of worse outcomes, these data suggest that patients with HR+/Basal tumors should not be treated uniformly with HR+/Luminal tumors and highlight the importance of further genomic classification for patients with HR+ tumors. Clinical trial information: NCT03053193.

Whole transcriptome analysis of tumors with discordant oncotype and MammaPrint results in the FLEX trial

556

Background: Genomic tests, such as MammaPrint (MP) and Oncotype DX Breast Recurrence Score (RS), assess risk of recurrence in patients with early breast cancer (EBC). Using both assays may yield discordant results which leads to uncertainty in treatment recommendations. The assays differ in technology and genes analyzed. RS relies on RT-PCR to query 16 cancer-related genes and 5 controls. MP uses a microarray to query 70 cancer-related genes and 465 normalization controls. Here we explore the genetic basis for discordance by using the FLEX whole transcriptome database to examine differentially expressed genes among patients who received discordant RS and MP results. Methods: Patients with EBC enrolled in the FLEX study (NCT03053193) undergo standard of care MP and BluePrint (BP) tests, and consent to clinically annotated whole transcriptome data collection. MP stratifies risk of recurrence as Low risk and High. RS classifies patients as Low Risk (RS 0-10), Intermediate (RS 11-25), and High Risk (RS 26-100). Due to low representation of BP Basal and BP HER2-type tumors in this data set, we only examined BP Luminal-type tumors (N = 705). We used full genome transcriptomes to compare gene expression among discordant cases. Gene expression data were quantile normalized and analyzed using R package ‘limma’. Genes were considered differentially expressed at a fold change of at least 1.7 and an adjusted p-value of lower than 0.05. To keep the analysis as unbiased as possible, comparisons between RS categories only included tumors within the same MP score range and similarly comparisons of MP categories only contained tumors within the same RS score range. Results: The comparisons between discordant cases, their numbers and the amount of differentially expressed genes (DEGs) are shown below. Sample sizes are shown in parentheses. Of the 49 DEGs found in the RS Intermediate group, several are associated with increased proliferation or increased metastatic potential. SCUBE2 and MMP9 were among the 49 genes and are among the 70-genes assayed by MP. Conclusions: The comparisons highlight the genomic diversity of the RS Intermediate (RS11-25) group, as seen with the high number of DEGs. MP separates cases into more genomically distinct categories, as reflected by fewer DEGs. Clinical trial information: NCT03053193. [Table: see text]

FLEX, the 30,000 breast cancer transcriptome project: A platform for early breast cancer research using full-genome arrays paired with clinical data

TPS612

Background: The ongoing, multi-center FLEX trial (NCT03053193) began in the United States in 2017, with the ultimate goal of 30,000 patients enrolled. The primary objective is to create a large-scale collaborative registry of early-stage breast cancer patients that links comprehensive clinical and full genome expression data to reveal new prognostic and/or predictive gene signatures. A key secondary objective of the trial is to enable investigator-initiated studies to explore early-stage breast cancer at a relatively low cost to the investigator. Methods: The prospective FLEX trial enrolls patients aged ≥ 18 years with histologically proven stage I-III breast cancer, with negative or 1-3 positive lymph nodes. Eligible patients have received MammaPrint, with or without BluePrint testing as standard of care, and consent to clinically annotated full transcriptome data collection. The FLEX base study protocol permits investigators to submit their own concept proposal, and upon review and approval by the Research and Scientific Review Committees, investigators interrogate clinical and genomic data from the FLEX database. The 10-year enrollment goal is a minimum of 30,000 patients. Since April 2017, 9,170 patients have been enrolled at over 109 sites in the United States. To date, 38 investigator-initiated substudies have been approved and are in progress, and 28 abstracts have been published in the US scientific congresses. To ensure inclusion of diverse populations, patients from local communities and 11 National Cancer Institute-designated Comprehensive Cancer Centers were included. Our diverse data set is helping meet the needs of historically under-represented patients with breast cancer. Of the self-reported ethnicities within the FLEX database, 65% are White or Caucasian, 8% Black or African American, 4% Latin American, and 2% Asian. There are 5 ongoing FLEX sub studies investigating racial disparities. The molecular profiling and differential gene expression analysis in early-stage breast cancer patients of African American, Asian, Hispanic ancestries helps to provide critical insights that correlate tumor biology with treatment outcomes. FLEX is expanding globally with sites anticipated in multiple European countries. The FLEX trial continues to expedite the discovery and development of novel genomic profiles, bringing precision oncology into the clinic to improve breast cancer management. Clinical trial information: NCT03053193.

Utility of the 70-gene MammaPrint assay for prediction of benefit from extended letrozole therapy (ELT) in the NRG Oncology/NSABP B-42 trial

502

Background: The 70-gene MammaPrint (MP) assay predicts risk of distant recurrence (DR) in hormone-receptor positive early-stage breast cancer and classifies cancers as Low Risk or High Risk. NSABP B-42 evaluated ELT in patients (pts) who had completed 5 yrs of adjuvant endocrine therapy (tx). The primary objective was to determine the utility of MP to identify pts enrolled in NSABP B-42 who are likely to benefit from ELT. Methods: A total of 1,866 pts from B-42 had available MP results. Primary endpoint is DR. Secondary endpoints are disease-free survival (DFS) and breast cancer-free interval (BCFI). For the primary analysis, pts were classified as High Risk (MP-H) (MP score ≤0.000) or Low Risk (MP-L) (MP score > 0.000). Exploratory analyses were performed for MP-L subcategories: MP Ultralow Risk (MP-UL) (MP score > 0.355) and MP-L but not MP-UL (MP-LNUL) (MP score > 0.000, ≤0.355). Likelihood ratio test based on stratified Cox proportional hazards (PH) model was used for treatment by risk group interaction. Stratified log-rank test was used to compare treatment groups. Hazard ratios and 95% CI were computed based on the stratified Cox PH model. Results: Among 1,866 pts, 706 (38%) were MP-H and 1,160 (62%) were MP-L. Of the MP-L, 252 (22%) were MP-UL. There were no significant differences in the distribution of patient and tumor characteristics between the MP group and the rest of the B-42 cohort, except for HER2 status. ELT effect was more pronounced in the MP cohort than in the overall B-42 population. For DR, there was statistically significant ELT benefit in MP-L (HR = 0.43, 95% CI 0.25-0.74, p = 0.002), but not MP-H (HR = 0.65, 0.34-1.24, p = 0.19) (interaction p = 0.38). For DFS, there was statistically significant ELT benefit in MP-L, but not MP-H (interaction p = 0.015). Similar findings were observed for BCFI (interaction p = 0.006). Within subcategories of MP-L, there was statistically significant ELT benefit in MP-LNUL, but not in MP-UL for all three endpoints, however the power in MP-UL was limited due to low number of pts (Table). Clinical trial information: 00382070. Conclusions: Statistically significant ELT benefit was observed for MP-L, but not MP-H. The treatment by risk group interaction was not statistically significant for DR, but it was for DFS and BCFI. The benefit appears to be stronger in MP-LNUL than in MP-UL. NCT: 00382070. Support: U10CA180868, -180822, U24CA196067; Novartis; Agendia.[Table: see text]

Race and response to neoadjuvant chemotherapy according to MammaPrint risk

578

Background: African-American (AA) women with breast cancer have a less favorable prognosis, likely due to differences in tumor biology. This is not only driven by the higher rate of triple negative/basal tumors in patients with AA ancestry, as worse outcome has also been seen in patients with luminal tumors. The Neoadjuvant BReast Cancer Symphony Trial (NBRST, NCT01479101) was a prospective trial that has shown an association of MammaPrint/BluePrint (MP/BP) with a rate of pathologic Complete Response (pCR) of 2% in Luminal A with 95% Distant Metastasis Free Interval at 3 years. Here, we determine the MP/BP risk distribution, response to therapy, and outcome in African American (AA) and Caucasian (Cau) patients. Methods: NBRST enrolled 1,072 breast cancer patients (pts) in the US (June 2011 and December 2014), median follow-up 34.9 months. The current unplanned analysis compared clinicopathological characteristics, molecular risk assignment and outcome with neoadjuvant chemotherapy (NACT) in AA and Cau pts. Molecular subtyping groups were assessed by MP/BP as follows: Luminal A (MammaPrint Low Risk), Luminal B (MammaPrint High Risk), HER2 and Basal types. Results: Out of 1,072 pts, 157 (15%) were AA, and 780 (73%) were Cau. AA patients were younger at diagnosis (52 vs 54 yrs; p = 0.016), had a higher likelihood of having higher grade (gr 3, 65% vs 53%; p = 0.005), ER-negative (45% vs 33%; p = 0.005) and lymph node positive tumors (71% vs 51; p < 0.001). MP/BP classified more AA patients as Basal type, 45% compared to 33% of Cau patients (p = 0.004). Fewer AA patients were classified as Luminal A (15%) compared to Cau pts (33%; p = 0.004). In multivariate analysis race was a significant factor for higher pCR rates to NACT in AA compared to Cau pts, together with PR, HER2, T-stage and Grade (HR = 1.679, 95% CI = (1.057, 2.67), p = 0.028). The pCR rate to NACT in patients with Basal tumors was 38% and similar in AA and Cau patients. In patients with hormone receptor positive and HER2 negative tumors, patients classified by MP/BP as Luminal A had lower pCR (2%) compared to non-luminal A (13%) (p = 0.0015). MP low risk patients had higher 3 yr DMFS (97%) than MP high risk patients (86%; p = 0.010). DMFS for AA MP Low Risk patients was 100%. Conclusions: In this study, MP was able to identify patients with hormone receptor positive tumors with low sensitivity to chemotherapy and good outcome, irrespective of race, suggesting that this test can be helpful to characterize the tumor’s biology and select patients who will not benefit from chemotherapy independently of their ancestry. Clinical trial information: NCT01479101.

A breast cancer gene signature for indolent disease

PURPOSE

Early-stage hormone-receptor positive breast cancer is treated with endocrine therapy and the recommended duration of these treatments has increased over time. While endocrine therapy is considered less of a burden to patients compared to chemotherapy, long-term adherence may be low due to potential adverse side effects as well as compliance fatigue. It is of high clinical utility to identify subgroups of breast cancer patients who may have excellent long-term survival without or with limited duration of endocrine therapy to aid in personalizing endocrine treatment.

METHODS

We describe a new ultralow risk threshold for the 70-gene signature (MammaPrint) that identifies a group of breast cancer patients with excellent 20 year, long-term survival prognosis. Tumors of these patients are referred to as "indolent breast cancer." We used patient series on which we previously established and assessed the 70-gene signature high-low risk threshold.

RESULTS

In an independent validation cohort, we show that patients with indolent breast cancer had 100% breast cancer-specific survival at 15 years of follow-up.

CONCLUSIONS

Our data indicate that patients with indolent disease may be candidates for limited treatment with adjuvant endocrine therapy based on their very low risk of distant recurrences or death of breast cancer.

Abstract P6-11-03: A phase 2 open-label study of lucitanib in patients (pts) with FGF aberrant metastatic breast cancer (MBC)

BACKGROUND: Lucitanib is a potent, oral antiangiogenic tyrosine kinase inhibitor of Vascular Endothelial Growth Factor Receptors 1-3 (VEGFR1-3), Platelet-Derived Growth Factor Receptors alpha and beta (PDGFRα/β), and Fibroblast Growth Factor Receptors 1-3 (FGFR1-3). FGF aberrancies (amplification of FGFR1,or 11q[amplicon containing FGF ligands 3, 4, and 19]), are genomic alterations observed in over 20% of breast cancer pts and promote cancer proliferation and survival.

METHODS: MBC pts who had received at least 1 metastatic line of therapy were randomized 1:1 to 10 or 15 mg QD of lucitanib. Stratification was based on local assessment of FGF aberrancy; pts with both FGFR1 and 11q-amplified tumors were stratified as FGFR1 amplified. Central confirmation of FGFR1 or 11q amplification was done using Abbott FISH probes (FGFR1 or 11q copy number ≥ 6 and a ratio of FGFR1 or 11q to centromere ≥ 2). Investigator-assessed progression-free survival (PFS) was the primary endpoint. Secondary endpoints included objective response rate (ORR) per RECIST 1.1, disease control rate (DCR), duration of response (DR), and incidence of treatment-emergent adverse events (TEAE).

RESULTS: Enrollment completed in 3/2016; 178 pts that received at least 1 dose of lucitanib are included in this analysis (baseline characteristics in Table 1). Due to grade 3 hypertension in the 15 mg group (46% vs 37% in 10 mg group), enrollment to the 15 mg group was halted. Overall, most pts (97%) experienced at least 1 TEAE, with the most frequently (≥ 30%) occurring events being hypertension (73%), fatigue (48%), nausea (43%), hypothyroidism (40%), and headache (33%). Grade ≥ 3 TEAEs occurred in 66% of pts, with hypertension as the most frequent event (40%) followed by proteinuria and hyponatremia (both 6%). AEs were manageable with dose interruption or reduction, with approximately 8% of pts ending treatment due to an AE. Current median PFS is 3.5 mos (95% CI 2.8-4.6; range 0.62-12.95) and 2.6 mos (95% CI 1.8-2.9; range 0.82-18.87) respectively for the 10 mg and 15 mg treatment groups. No differences in clinical activity were observed by treatment group, FGF aberrancy, hormone receptor or HER2 status. Of the 168 evaluable pts, confirmed ORR was 3%; overall DCR was 27% (32% for pts in the 10 mg group compared to 20% for the 15 mg group); overall mean (standard deviation) DR of 3.3 (1.8) mos.

Baseline Characteristics 10 mg QD15 mg QD N=109N=69Age (years)Median5653Range27-8227-80SexFemale109 (100%)67 (97%)Male02 (3%)ECOG PSmissing5 (5%)2 (3%)051 (47%)30 (43%)153 (49%)37 (54%)Number of prior anticancer therapies in the metastatic setting&gt; 332 (29%)21 (30%)3-648 (44%)32 (46%)&gt; 629 (27%)16 (23%)Endocrine/HER2 statusmissing7 (6%)1 (1%)ER+ or PR+74 (68%)50 (73%)HER2+12 (11%)7 (10%)TNBC16 (15%)11 (16%)FGFR aberrancyFGFR1 amplified54 (49%)29 (42%)11q amplified31 (28%)24 (35%)FGFR1 and 11q amplified13 (12%)9 (13%)FGFR1 and 11q non-amplified11 (10%)7 (10%)

CONCLUSION: At 10 mg QD, lucitanib has modest activity with manageable toxicity in this heavily pretreated pt population. Future clinical development for lucitanib may focus on alternative biomarkers to identify sensitive tumors and rational combinations with other anti-cancer drugs.

Citation Format: Mayer IA, Arteaga CL, Nanda R, Miller KD, Jhaveri K, Brufsky AM, Rugo H, Yardley DA, Vahdat LT, Sadeghi S, Audeh MW, Rolfe L, Litten J, Knox A, Raponi M, Tankersley C, Isaacson J, Wride K, Morganstern DE, Vogel C, Connolly RM, Gradishar WJ, Patel R, Pusztai L, Abu-Khalaf M. A phase 2 open-label study of lucitanib in patients (pts) with FGF aberrant metastatic breast cancer (MBC) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-11-03.

Abstract P4-04-01: PDL-1 expression in primary breast cancers with germline mutations in BRCA 1 and 2

Background: The PD-1/PDL-1 pathway is a major inhibitory regulator of the immune response to tumors. Tumors responding to anti-PD-1 therapy appear to be characterized by a high "load" of somatic mutations, e.g.carcinogen-induced cancers (melanoma, lung) and tumors with a high intrinsic mutation rate (colorectal cancers with defects in DNA mismatch repair).High mutational load in these tumors may cause the expression of neoantigens which may induce an immune response unless the inhibitory PD-1/PDL-1 pathway is upregulated.Tumors in carriers of germline mutations in BRCA1/2 lack effective DNA repair and are genomically unstable, with a high mutational load and the possible expression of neoantigens. Breast cancers arising in carriers of germline mutations in BRCA1 and BRCA2 may rely on the PD-1/PDL-1 pathway to avoid immune destruction. Methods: Samples from thirty (30) treatment-naïve, primary breast cancers from 30 women with known germline mutations in BRCA 1 or BRCA2 were identified by records review in the Cedars-Sinai Department of Pathology, and selected for analysis of PD-1 and PDL-1 expression. Samples were analyzed for PD1 and PDL-1 expression utilizing immunohistochemical staining. Sections from FFPE tissue blocks were analysed with anti-PD-L1 clone 22C3(Merck); anti-PD-L1 clone SP142; or anti-PD-1 clone NAT105. IHC Scoring analyzed both tumor cell and non-tumor cell (inflammatory) infiltrate. A 0-5 scoring system (0= neg, 1 = rare, 2 = low, 3 = mod, 4 = high, 5 = very high) was applied. Tumors with IHC scores of 2 or greater were considered "positive" for expression of PD1 or PDL-1. Clinical Data: Age range 39-90 years, median age 61. Twenty(20) tumors were from BRCA 1 mutations carriers, and 10 were BRCA2. Sixteen (16) were basal type breast cancer (13 BRCA1, 3 BRCA2), 14 were estrogen receptor positive(ER+)(7 BRCA1, 7BRCA2), with 7 Luminal A and 7 Luminal B. There were no HER2 -amplified tumors in the cohort.Results: PD1 expression was observed in 11/30 (37%) of the cohort, and PDL-1 expression was detected in 21/30 (70%) of the cohort. PDL-1 expression was primarily seen in non-tumor, infiltrating immune cells. PDL-1 expression was seen in 15/20 (75%) of tumors from BRCA1 mutation carriers, and 6/10 (60%) of tumors from BRCA2 carriers. PDL-1 expression was present in 13/16 (81%) basal tumors and 8/14 (57%) ER+ tumors. Within the cohort of PDL-1 expressing cancers, 7/21 (33%) were scored as "high" or "very high", 5 basal breast cancers and 2 ER+ cancers. Conclusion: The current study has identified a high rate of PDL-1 expression in untreated primary breast cancers with germline BRCA1 and BRCA2 mutations, regardless of intrinsic subtype. Although the highest rate of expression was seen in basal breast cancers (81%), the majority of ER+ breast cancers, both Luminal A and Luminal B, also expressed PDL-1. Anti-PD-1 therapy has yielded a response rate of 19% in metastatic triple negative breast cancer, unselected for BRCA mutation.The current study suggests that tumors in carriers of germline mutations in BRCA1 or BRCA2 , regardless of intrinsic subtype, may rely on immune checkpoint inhibition for their growth and survival, and that therapy directed against the PD-1/PDL-1 pathway may be of benefit in this cohort of patients.

Citation Format: Audeh MW, Dadmanesh F, Yearley J. PDL-1 expression in primary breast cancers with germline mutations in BRCA 1 and 2. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-04-01.

Efficacy and safety of olaparib monotherapy in germline BRCA1/2 mutation carriers with advanced ovarian cancer and three or more lines of prior therapy

OBJECTIVE

The efficacy and safety of olaparib, an oral poly(ADP-ribose) polymerase (PARP) inhibitor, was investigated in a subgroup of patients with germline BRCA1/2 mutated (gBRCA1/2m) advanced ovarian cancer who had received ≥3 prior lines of chemotherapy. Primary data from this Phase II study (Study 42, ClinicalTrials.govNCT01078662) have been reported previously.

METHODS

Eligible patients were treated with oral olaparib 400mg bid capsule monotherapy until disease progression according to RECIST v1.1. Objective response rate (ORR) and duration of response (DoR) were assessed for patients with measurable disease at baseline. Safety and tolerability were assessed for all patients by adverse event (AE) incidence and changes in laboratory parameters. Platinum resistance status was obtained retrospectively, and responses to olaparib evaluated.

RESULTS

In patients with gBRCA1/2m ovarian cancer, 154/193 (80%) had received ≥3 prior lines of chemotherapy, of whom 137/154 (89%) had measurable disease at baseline. ORR was 34% (46/137; 95% confidence interval [CI] 26-42) and median DoR was 7.9 (95% CI 5.6-9.6) months. ORR in platinum-resistant tumors was 30%. Median DoR for platinum-sensitive and platinum-resistant disease was similar: 8.2months (95% CI 5.6-13.5) compared with 8.0months (4.8-14.8), respectively. Six of the 193 (3%) patients had an AE with an outcome of death. None of these AEs at time of occurrence was considered causally related to olaparib.

CONCLUSION

Following ≥3 prior lines of chemotherapy, olaparib 400mg bid (capsule form) monotherapy demonstrated notable antitumor activity in patients with gBRCA1/2m advanced ovarian cancer. No new safety signals were identified.

Olaparib monotherapy in patients with advanced cancer and a germline BRCA1/2 mutation

PURPOSE

Olaparib is an oral poly (ADP-ribose) polymerase inhibitor with activity in germline BRCA1 and BRCA2 (BRCA1/2) -associated breast and ovarian cancers. We evaluated the efficacy and safety of olaparib in a spectrum of BRCA1/2-associated cancers.

PATIENTS AND METHODS

This multicenter phase II study enrolled individuals with a germline BRCA1/2 mutation and recurrent cancer. Eligibility included ovarian cancer resistant to prior platinum; breast cancer with ≥ three chemotherapy regimens for metastatic disease; pancreatic cancer with prior gemcitabine treatment; or prostate cancer with progression on hormonal and one systemic therapy. Olaparib was administered at 400 mg twice per day. The primary efficacy end point was tumor response rate.

RESULTS

A total of 298 patients received treatment and were evaluable. The tumor response rate was 26.2% (78 of 298; 95% CI, 21.3 to 31.6) overall and 31.1% (60 of 193; 95% CI, 24.6 to 38.1), 12.9% (eight of 62; 95% CI, 5.7 to 23.9), 21.7% (five of 23; 95% CI, 7.5 to 43.7), and 50.0% (four of eight; 95% CI, 15.7 to 84.3) in ovarian, breast, pancreatic, and prostate cancers, respectively. Stable disease ≥ 8 weeks was observed in 42% of patients (95% CI, 36.0 to 47.4), including 40% (95% CI, 33.4 to 47.7), 47% (95% CI, 34.0 to 59.9), 35% (95% CI, 16.4 to 57.3), and 25% (95% CI, 3.2 to 65.1) of those with ovarian, breast, pancreatic, or prostate cancer, respectively. The most common adverse events (AEs) were fatigue, nausea, and vomiting. Grade ≥ 3 AEs were reported for 54% of patients; anemia was the most common (17%).

CONCLUSION

Responses to olaparib were observed across different tumor types associated with germline BRCA1/2 mutations. Olaparib warrants further investigation in confirmatory studies.

Utilizing Eastern Cooperative Oncology Group (ECOG) performance status scores to prevent harm with chemotherapy at the end of life

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Background: According to ASCO’s “top five” list of non evidence-based cancer treatments and procedures, the use of chemotherapy in solid tumor patients with evidence of poor performance status is at the top of the list. The Dartmouth Atlas report revealed a significant overuse of chemotherapy at the end of life (EOL), and Cedars-Sinai was identified as an outlier with regards to this practice. Methods: Cedars-Sinai’s interdisciplinary cancer quality committee designed a new initiative to eliminate the ineffective administration of chemotherapy. Each patient’s ECOG score, entered by a nurse or physician, was used as an appropriateness screen by pharmacists before they released chemotherapy in both the outpatient and inpatient settings. If a patient did not qualify for chemotherapy based on an ECOG score of 3 or greater, the pharmacist contacted the prescribing oncologist to discuss the case. Ultimately the oncologist had the final say as to whether the patient received chemotherapy. Data was collected on ECOG scores, number of patients screened and identified as being at risk, oncologists’ responses to being notified, and whether chemotherapy was ultimately administered. Results: Available data collected on the % of orders with ECOG scores, since February of 2014 is shown in the Table. Conclusions: Data and conclusions regarding oncologists’ responses to being notified, and whether chemotherapy was ultimately administered, and harm thus prevented, is currently being compiled and will be presented at the conference. [Table: see text]

Novel treatment strategies in triple-negative breast cancer: specific role of poly(adenosine diphosphate-ribose) polymerase inhibition

Inhibitors of the poly(adenosine triphosphate-ribose) polymerase (PARP)-1 enzyme induce synthetic lethality in cancers with ineffective DNA (DNA) repair or homologous repair deficiency, and have shown promising clinical activity in cancers deficient in DNA repair due to germ-line mutation in BRCA1 and BRCA2. The majority of breast cancers arising in carriers of BRCA1 germ-line mutations, as well as half of those in BRCA2 carriers, are classified as triple-negative breast cancer (TNBC). TNBC is a biologically heterogeneous group of breast cancers characterized by the lack of immunohistochemical expression of the ER, PR, or HER2 proteins, and for which the current standard of care in systemic therapy is cytotoxic chemotherapy. Many "sporadic" cases of TNBC appear to have indicators of DNA repair dysfunction similar to those in BRCA-mutation carriers, suggesting the possible utility of PARP inhibitors in a subset of TNBC. Significant genetic heterogeneity has been observed within the TNBC cohort, creating challenges for interpretation of prior clinical trial data, and for the design of future clinical trials. Several PARP inhibitors are currently in clinical development in BRCA-mutated breast cancer. The use of PARP inhibitors in TNBC without BRCA mutation will require biomarkers that identify cancers with homologous repair deficiency in order to select patients likely to respond. Beyond mutations in the BRCA genes, dysfunction in other genes that interact with the homologous repair pathway may offer opportunities to induce synthetic lethality when combined with PARP inhibition.

Olaparib monotherapy in patients with advanced cancer and a germ-line BRCA1/2 mutation: An open-label phase II study

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Background: The oral PARP inhibitor olaparib has shown antitumor activity as monotherapy in patients (pts) with breast and ovarian cancer with gBRCA1/2 mutations. This multicenter non-comparative study evaluated whether tumors in gBRCA1/2 mutation carriers are responsive to olaparib regardless of tumor type (NCT01078662). Methods: Heavily pretreated pts with advanced cancer refractory to standard therapy (98% of breast cancer pts had ≥3 lines of prior chemotherapy for metastatic disease) and with a gBRCA1/2 mutation, received olaparib 400 mg bid (capsule) until disease progression. Primary objective: tumor response by RECIST 1.1. Secondary objectives: PFS, OS and safety. Results: 298 pts received treatment and were evaluable. Enrollment is complete, 33 pts remain on study. Median duration of treatment in this heavily pretreated population was 5.5 months (range <1–28.5 months). Most common AEs (generally grade 1/2) were fatigue (59%), nausea (59%) and vomiting (37%). Grade ≥3 AEs were reported for 162 pts (54%); most common was anemia (17%). 11 pts (4%) had AEs that led to treatment discontinuation. Conclusions: The observedtumor response rates indicate antitumor activity of olaparib monotherapy in gBRCA mutated pts with advanced cancer refractory to standard therapy. A clinical benefit was seen in prostate and pancreatic cancer and activity in ovarian and breast cancer was confirmed. Prolonged responses to olaparib across all tumor types support the hypothesis that therapy directed against a genetically-defined target has activity regardless of anatomic organ of origin. Olaparib was generally well tolerated with toxicities consistent with prior studies. Clinical trial information: NCT01078662. [Table: see text]

Oral poly(ADP-ribose) polymerase inhibitor olaparib in patients with BRCA1 or BRCA2 mutations and recurrent ovarian cancer: a proof-of-concept trial

BACKGROUND

Olaparib is a novel, orally active poly(ADP-ribose) polymerase (PARP) inhibitor that induces synthetic lethality in homozygous BRCA-deficient cells. We aimed to assess the efficacy and safety of olaparib for treatment of advanced ovarian cancer in patients with BRCA1 or BRCA2 mutations.

METHODS

In this international, multicentre, phase 2 study, we enrolled two sequential cohorts of women (aged >or=18 years) with confirmed genetic BRCA1 or BRCA2 mutations, and recurrent, measurable disease. The study was undertaken in 12 centres in Australia, Germany, Spain, Sweden, and the USA. The first cohort (n=33) was given continuous oral olaparib at the maximum tolerated dose of 400 mg twice daily, and the second cohort (n=24) was given continuous oral olaparib at 100 mg twice daily. The primary efficacy endpoint was objective response rate (ORR). This study is registered with ClinicalTrials.gov, number NCT00494442.

FINDINGS

Patients had been given a median of three (range 1-16) previous chemotherapy regimens. ORR was 11 (33%) of 33 patients (95% CI 20-51) in the cohort assigned to olaparib 400 mg twice daily, and three (13%) of 24 (4-31) in the cohort assigned to 100 mg twice daily. In patients given olaparib 400 mg twice daily, the most frequent causally related adverse events were nausea (grade 1 or 2, 14 [42%]; grade 3 or 4, two [6%]), fatigue (grade 1 or 2, ten [30%]; grade 3 or 4, one [3%]), and anaemia (grade 1 or two, five [15%]; grade 3 or 4, one [3%]). The most frequent causally related adverse events in the cohort given 100 mg twice daily were nausea (grade 1 or 2, seven [29%]; grade 3 or 4, two [8%]) and fatigue (grade 1 or 2, nine [38%]; none grade 3 or 4).

INTERPRETATION

Findings from this phase 2 study provide positive proof of concept of the efficacy and tolerability of genetically targeted treatment with olaparib in BRCA-mutated advanced ovarian cancer.

FUNDING

AstraZeneca.

Oral poly(ADP-ribose) polymerase inhibitor olaparib in patients with BRCA1 or BRCA2 mutations and advanced breast cancer: a proof-of-concept trial

BACKGROUND

Olaparib, a novel, orally active poly(ADP-ribose) polymerase (PARP) inhibitor, induced synthetic lethality in BRCA-deficient cells. A maximum tolerated dose and initial signal of efficacy in BRCA-deficient ovarian cancers have been reported. We therefore assessed the efficacy, safety, and tolerability of olaparib alone in women with BRCA1 or BRCA2 mutations and advanced breast cancer.

METHODS

Women (aged >or=18 years) with confirmed BRCA1 or BRCA2 mutations and recurrent, advanced breast cancer were assigned to two sequential cohorts in a phase 2 study undertaken in 16 centres in Australia, Germany, Spain, Sweden, the UK, and the USA. The first cohort (n=27) was given continuous oral olaparib at the maximum tolerated dose (400 mg twice daily), and the second (n=27) was given a lower dose (100 mg twice daily). The primary efficacy endpoint was objective response rate (ORR). This study is registered with ClinicalTrials.gov, number NCT00494234.

FINDINGS

Patients had been given a median of three previous chemotherapy regimens (range 1-5 in cohort 1, and 2-4 in cohort 2). ORR was 11 (41%) of 27 patients (95% CI 25-59) in the cohort assigned to 400 mg twice daily, and six (22%) of 27 (11-41) in the cohort assigned to 100 mg twice daily. Toxicities were mainly at low grades. The most frequent causally related adverse events in the cohort given 400 mg twice daily were fatigue (grade 1 or 2, 11 [41%]; grade 3 or 4, four [15%]), nausea (grade 1 or 2, 11 [41%]; grade 3 or 4, four [15%]), vomiting (grade 1 or 2, three [11%]; grade 3 or 4, three [11%]), and anaemia (grade 1 or 2, one [4%]; grade 3 or 4, three [11%]). The most frequent causally related adverse events in the cohort given 100 mg twice daily were nausea (grade 1 or 2, 11 [41%]; none grade 3 or 4) and fatigue (grade 1 or 2, seven [26%]; grade 3 or 4, one [4%]).

INTERPRETATION

The results of this study provide positive proof of concept for PARP inhibition in BRCA-deficient breast cancers and shows a favourable therapeutic index for a novel targeted treatment strategy in patients with tumours that have genetic loss of function of BRCA1-associated or BRCA2-associated DNA repair. Toxicity in women with BRCA1 and BRCA2 mutations was similar to that reported previously in those without such mutations.

FUNDING

AstraZeneca.

A phase II trial of carbetimer for the treatment of colorectal cancer. A trial of the Northern California Oncology Group

Carbetimer (carboxyimamidate) was administered at a dose of 6,500 mg/m2/day intravenously for 5 consecutive days to 14 patients with measurable metastatic or recurrent colorectal cancer in a single institution phase II study of the Northern California Oncology Group. A total of 38 cycles of therapy were administered; nine patients completed at least three cycles of treatment. No partial or complete responses were observed. One patient did have a greater than 50% response in the liver while developing new retroperitoneal lymphadenopathy and is considered a nonresponder. Carbetimer was well tolerated with elevations of calcium from 10.2 to 12.5 mg/dl in nine patients, prolongation of prothrombin time and partial thromboplastin time in 14 patients, proteinuria in 10 patients, dizziness in six patients, nausea in two patients, and venous pain during infusion in three patients. Myelosuppression was not observed. Carbetimer at this dose and schedule is inactive in the treatment of colorectal cancer.

Immunophenotypic differences between plasmacytoma/multiple myeloma and immunoblastic lymphoma

Four cases of plasmacytoma (PC), six cases of multiple myeloma (MM), and nine cases of immunoblastic lymphoma (IL) of B-cell phenotype were studied with a large panel of monoclonal antibodies applied to frozen tissue sections. There were no significant differences in the immunophenotypes of plasmacytomas and multiple myelomas. However, significant immunophenotypic differences were noticed between the plasmacytoma/multiple myeloma cases (PC/MM) and the immunoblastic lymphoma specimens. The PC/MM cases characteristically stained with alpha (or gamma) and T10 and did not usually stain with mu, leukocyte common antibodies, certain B-lineage antibodies (B1, T015, 4G7, 6A4), or Ia. In contrast, IL sections usually did not stain with alpha or T10 and generally did stain with mu (or gamma), leukocyte common antibodies, B-lineage antibodies, and Ia. Ki-67, an antibody to proliferating cells, stained significantly fewer cells in PC/MM than in IL and stained significantly fewer cells that had a good clinical outcome. We conclude that although no one antibody is useful in distinguishing PC/MM from IL, the application of a panel of antibodies may be helpful in making this distinction. The prognosis may correlate with the numbers of proliferating cells as measured by reactivity with Ki-67.

Small cell lung carcinoma in the elderly

Twenty-four patients over the age of 70 with small cell cancer of the lung were studied retrospectively. Ninety-two per cent of these patients had other concurrent medical disorders; 58 per cent had cardiac disease and 25 per cent had a second malignancy. The median survival of 20 treated patients was ten months, and the one-year survival was 30 per cent. Such elderly patients with multiple medical problems can benefit from combination chemotherapy.