Alpha-methylacyl-CoA racemase (AMACR) was first discovered by using cDNA microarray technology as a molecular marker for prostate cancer. Our recent microarray analysis of renal cell carcinomas showed a significant increase of AMACR mRNA levels in papillary renal cell carcinomas, but not in other subtypes. To investigate the value of this marker in pathologic diagnosis, we analyzed AMACR mRNA levels in cDNA microarrays from 70 kidney tumors. Furthermore, we evaluated the AMACR expression in 165 kidney tumors on tissue microarrays and 51 papillary carcinomas of other organs by immunohistochemistry. AMACR mRNA was significantly overexpressed in 7 of 8 papillary renal cell carcinomas with an average of 5.2-fold increase, and only in 2 of 62 nonpapillary kidney tumors. Immunohistochemistry demonstrated strong AMACR positivity in all cases of papillary renal cell carcinomas (41 of 41, 100%), including 6 metastatic papillary renal cell carcinomas, but only focal or weak reactivity in the minority (18 of 124, 15%) of other renal tumors including 13 of 52 clear cell renal cell carcinomas, 3 of 20 oncocytomas, and 2 of 17 urothelial carcinomas. All chromophobe (0 of 18) and sarcomatoid components of renal cell carcinomas (0 of 15) were negative for AMACR. Weak or focal AMACR immunoreactivity was detected in only 4 of 51 (8%) papillary carcinomas arising in other organs (2 of 14 thyroid, 2 of 13 lung, 0 of 6 breast, 0 of 6 endometrium, 0 of 6 ovary, and 0 of 6 pancreas). Using a combination of cDNA microarrays, tissue microarrays, and immunohistochemistry, we identified AMACR as a marker for papillary renal cell carcinoma, which could be valuable in subclassification of renal cell carcinomas and in the differential diagnosis of a metastatic papillary carcinoma.

Background Previous studies have independently validated the prognostic relevance of residual cancer burden (RCB) after neoadjuvant chemotherapy. We used results from several independent cohorts in a pooled patient-level analysis to evaluate the relationship of RCB with long-term prognosis across different phenotypic subtypes of breast cancer, to assess generalisability in a broad range of practice settings. MethodsIn this pooled analysis, 12 institutes and trials in Europe and the USA were identified by personal communications with site investigators. We obtained participant-level RCB results, and data on clinical and pathological stage, tumour subtype and grade, and treatment and follow-up in November, 2019, from patients (aged ≥18 years) with primary stage I-III breast cancer treated with neoadjuvant chemotherapy followed by surgery. We assessed the association between the continuous RCB score and the primary study outcome, event-free survival, using mixed-effects Cox models with the incorporation of random RCB and cohort effects to account for betweenstudy heterogeneity, and stratification to account for differences in baseline hazard across cancer subtypes defined by hormone receptor status and HER2 status. The association was further evaluated within each breast cancer subtype in multivariable analyses incorporating random RCB and cohort effects and adjustments for age and pretreatment clinical T category, nodal status, and tumour grade. Kaplan-Meier estimates of event-free survival at 3, 5, and 10 years were computed for each RCB class within each subtype. FindingsWe analysed participant-level data from 5161 patients treated with neoadjuvant chemotherapy between Sept 12, 1994, and Feb 11, 2019. Median age was 49 years (IQR 20-80). 1164 event-free survival events occurred during follow-up (median follow-up 56 months [IQR 0-186]). RCB score was prognostic within each breast cancer subtype, with higher RCB score significantly associated with worse event-free survival. The univariable hazard ratio (HR) associated with one unit increase in RCB ranged from 1•55 (95% CI 1•41-1•71) for hormone receptor-positive, HER2-negative patients to 2•16 (1•79-2•61) for the hormone receptor-negative, HER2-positive group (with or without HER2-targeted therapy; p<0•0001 for all subtypes). RCB score remained prognostic for eventfree survival in multivariable models adjusted for age, grade, T category, and nodal status at baseline: the adjusted HR ranged from 1•52 (1•36-1•69) in the hormone receptor-positive, HER2-negative group to 2•09 (1•73-2•53) in the hormone receptor-negative, HER2-positive group (p<0•0001 for all subtypes).Interpretation RCB score and class were independently prognostic in all subtypes of breast cancer, and generalisable to multiple practice settings. Although variability in hormone receptor subtype definitions and treatment across patients are likely to affect prognostic performance, the association we observed between RCB and a patient's residual risk suggests that prospective evaluation of RCB could be c...

I-SPY2 Trial ConsortiumIMPORTANCE Pathologic complete response (pCR) is a known prognostic biomarker for long-term outcomes. The I-SPY2 trial evaluated if the strength of this clinical association persists in the context of a phase 2 neoadjuvant platform trial.OBJECTIVE To evaluate the association of pCR with event-free survival (EFS) and pCR with distant recurrence-free survival (DRFS) in subpopulations of women with high-risk operable breast cancer treated with standard therapy or one of several novel agents. DESIGN, SETTING, AND PARTICIPANTSMulticenter platform trial of women with operable clinical stage 2 or 3 breast cancer with no prior surgery or systemic therapy for breast cancer; primary tumors were 2.5 cm or larger. Women with tumors that were ERBB2 negative/hormone receptor (HR) positive with low 70-gene assay score were excluded. Participants were adaptively randomized to one of several different investigational regimens or control therapy within molecular subtypes from March 2010 through 2016. The analysis included participants with follow-up data available as of February 26, 2019.INTERVENTIONS Standard-of-care neoadjuvant therapy consisting of taxane treatment with or without (as control) one of several investigational agents or combinations followed by doxorubicin and cyclophosphamide.MAIN OUTCOMES AND MEASURES Pathologic complete response and 3-year EFS and DRFS. RESULTSOf the 950 participants (median [range] age, 49 [23-77] years), 330 (34.7%) achieved pCR. Three-year EFS and DRFS for patients who achieved pCR were both 95%. Hazard ratios for pCR vs non-pCR were 0.19 for EFS (95% CI, 0.12-0.31) and 0.21 for DRFS (95% CI, 0.13-0.34) and were similar across molecular subtypes, varying from 0.14 to 0.18 for EFS and 0.10 to 0.20 for DRFS. CONCLUSIONS AND RELEVANCEThe 3-year outcomes from the I-SPY2 trial show that, regardless of subtype and/or treatment regimen, including 9 novel therapeutic combinations, achieving pCR after neoadjuvant therapy implies approximately an 80% reduction in recurrence rate. The goal of the I-SPY2 trial is to rapidly identify investigational therapies that may improve pCR when validated in a phase 3 confirmatory trial. Whether pCR is a validated surrogate in the sense that a therapy that improves pCR rate can be assumed to also improve long-term outcome requires further study.

To evaluate the expression of cytokeratin (CK) 19, we stained sections obtained from formalin-fixed, paraffin tissue blocks of 35 thyroid tumors (follicular adenoma [FA], 20; papillary thyroid carcinoma [PTC], 10 follicular variant [FV] and 5 usual type) and scored the extent of staining as follows: 1+ (<5% positively stained cells), 2+ (5%-25% positively stained cells), 3+ (25%-75% positively stained cells), and 4+ (>75% positively stained cells). All 15 PTCs (including 10 FV-PTCs) were CK19 positive: 14 were 4+ and 1 (FV-PTC) was 2+. All 20 FAs also were CK19 positive: 15 were 1+, 1 was 2+, 4 were 3+, and none was 4+. In the FAs that were scored 1+, reactivity usually was confined to follicular cells lining cystically dilated atrophic follicles that lacked the typical nuclear features of PTC. The remaining FAs showed more diffuse reactivity, which was, however, less intense than that observed in the PTCs. Thus, immunoreactivity for CK19 is not specific for PTC, although we acknowledge that the extent and intensity of staining are considerably greater in this tumor than in FA. There were no significant differences in staining for CK19 between nonneoplastic follicles adjacent to PTCs and those adjacent to FAs.

Abstract. Animal models play a major role in understanding the etiology, molecular mechanisms, strategizing intervention and treatment of human diseases. ACI, an inbred line derived from August and Copenhagen strains, is unique for its susceptibility to estrogen-induced mammary tumors. Histologically and in many molecular aspects, the tumors formed in these rats are similar to human breast cancers. Previous studies have shown high mortality and significant weight loss in this model associated with pituitary gland abnormality. We hypothesized that this could be due to overwhelming the biological system with estrogen. Three groups of female ACI rats (7-8 weeks) received either 3-cm sham silastic implants, or the conventional 3-cm silastic implants containing 27 mg of 17ß-estradiol, or 1.2-cm silastic implants containing 9 mg 17ß-estradiol. The sham and 3-cm implant rats were euthanized at 180 days while the 1.2-cm implant rats were euthanized at 240 days. The 1.2-cm implants resulted in significantly reduced serum estrogen levels and pituitary gland size. Animals with 1.2-cm implants had 100% tumor incidence, while not all rats developed tumors with 3-cm implants. Both the tumor burden (from 1,011±402 to 2,324±454 mm 3 ; p=0.01) and tumor multiplicity (from 5.78±1.4 to 7.6±1.04) increased by lowering the estrogen dose, and the inter-animal variability in the tumor indices decreased. Finally, the weight of the pituitary gland was also significantly (p=0.0004) reduced (from 178±23.5 mg to 80±8.9 mg) and the mortality rate decreased from 42% to 0% (p=0.01). Our data indicate that the improvised model will provide valuable insights into the molecular alterations in the estrogen-induced mammary tumorigenesis and will be ideal for inhibition studies.