Prognostic value of histopathologic traits independent of stromal tumor-infiltrating lymphocyte levels in chemotherapy-naïve patients with triple-negative breast cancer

BACKGROUND

In the absence of prognostic biomarkers, most patients with early-stage triple-negative breast cancer (eTNBC) are treated with combination chemotherapy. The identification of biomarkers to select patients for whom treatment de-escalation or escalation could be considered remains an unmet need. We evaluated the prognostic value of histopathologic traits in a unique cohort of young, (neo)adjuvant chemotherapy-naïve patients with early-stage (stage I or II), node-negative TNBC and long-term follow-up, in relation to stromal tumor-infiltrating lymphocytes (sTILs) for which the prognostic value was recently reported.

MATERIALS AND METHODS

We studied all 485 patients with node-negative eTNBC from the population-based PARADIGM cohort which selected women aged <40 years diagnosed between 1989 and 2000. None of the patients had received (neo)adjuvant chemotherapy according to standard practice at the time. Associations between histopathologic traits and breast cancer-specific survival (BCSS) were analyzed with Cox proportional hazard models.

RESULTS

With a median follow-up of 20.0 years, an independent prognostic value for BCSS was observed for lymphovascular invasion (LVI) [adjusted (adj.) hazard ratio (HR) 2.35, 95% confidence interval (CI) 1.49-3.69], fibrotic focus (adj. HR 1.61, 95% CI 1.09-2.37) and sTILs (per 10% increment adj. HR 0.75, 95% CI 0.69-0.82). In the sTILs <30% subgroup, the presence of LVI resulted in a higher cumulative incidence of breast cancer death (at 20 years, 58%; 95% CI 41% to 72%) compared with when LVI was absent (at 20 years, 32%; 95% CI 26% to 39%). In the ≥75% sTILs subgroup, the presence of LVI might be associated with poor survival (HR 11.45, 95% CI 0.71-182.36, two deaths). We confirm the lack of prognostic value of androgen receptor expression and human epidermal growth factor receptor 2 -low status.

CONCLUSIONS

sTILs, LVI and fibrotic focus provide independent prognostic information in young women with node-negative eTNBC. Our results are of importance for the selection of patients for de-escalation and escalation trials.

Abstract P5-08-07: The long-term prognosis of breast cancers patients diagnosed ≤40 years in the absence of adjuvant systemic therapy

This abstract was withdrawn by the authors.

Molecular markers to differentiate between pancreatic cancer and normal pancreas/chronic pancreatitis: Gene expression profiling study

21150

Background: The aim of the study was to analyze the gene expression profile of pancreatic cancer by multivariate methods of class prediction. Methods: The snap-frozen or RNA-later preserved samples of 18 pancreatic adenocarcinomas, 9 chronic pancreatitis cases and 6 specimens collected from microscopically unchanged pancreas (N/CP) were analyzed by HG-U133 Plus 2.0 oligonucleotide microarrays (Affymetrix). The obtained dataset was pre-processed using GC-RMA method, gene selection was carried out both by class comparison methods (Welch test with Benjamini-Hochberg correction, False Discovery Rate FDR<5%) and by our own algorithms of class prediction, based on Support Vector Machines technique (Recurrent Feature Replacement and Bootstrap-Based Feature Ranking). Real- time quantitative PCR (Q-PCR) was carried out on Applied Biosystems 7900 HT machine, with Universal Probe Library (Roche) fluorescent probes and normalization by three reference genes index (geNorm, Vandesompele et al.). Results: We compared gene expression profiles between pancreatic cancer samples and N/CP specimens. 23850 probesets significantly differentiated between these three classes (FDR<5%). No ideal discrimination between cancer and N/CP samples was possible by any of single markers. We selected the optimal multi- gene classifier by Support Vector Machines, using Bootstrap-Based Feature Ranking method. The smallest classifier resulting in 100% accuracy consisted of three genes, 45 genes were included in more than half of the diagnostic genesets obtained during bootstrapping process. 14 genes were selected for Q-PCR validation, again none of them ideally discriminated between cancer and normal specimens, with the area under the receiver-operating-characteristic curve ranging from 0.82–0.93. Three-gene combinations allowed for proper classification of all samples. Conclusions: The multi-gene classifier, derived both by microarray technique and Q-PCR analysis, is properly discriminating between pancreatic cancer and chronic pancreatitis/normal pancreas. At least three genes must be included in the classifier to obtain satisfying accuracy. MO and MJ equally contributed to the study.

No significant financial relationships to disclose.

DNA ploidy assessment method applied to primary breast carcinoma FNA biopsies

The goal of our study was to assess suitability of FNA biopsy material as a source of samples (cell suspension) for DNA ploidy assessment in neoplastic tumors using flow cytometry. DNA ploidy is an established prognostic factor in many types of cancers. Aneuploid breast tumors are characterized by increased aggressiveness which manifests itself through rapid local progression and metastatic spread. Investigated specimens were breast cancer FNA biopsy cell suspensions. Measurements were performed using flow cytometry. Material studied comprised 143 cases analyzed in 1999-2000. We found in this group 101 carcinoma cases with aneuploid type and 42 cases of primary breast carcinoma with diploid type of cell cycle. Immunocytochemical assesssment of estrogen receptor and progesterone receptor status was performed in group of 105 cases. DNA ploidy was compared to receptor status of the investigated cells. DNA aneuploidy correlated with weak or no reaction for the presence of estrogen and progesterone receptors. Our study demonstrates the suitability of DNA ploidy assessment method applied to cytological material from FNA biopsies.

[Thyroglobulin RT-PCR method for detection of lymph node metastases during the course of differentiated thyroid cancers]

In patients with a suspicion of recurrence of differentiated thyroid cancer with metastases to lymph nodes, detection of thyroglobulin (Tg) mRNA in fine needle biopsy material may support the interpretation of classic cytological examination in cases where it fails to detect lymph node involvement early enough.

AIM

Prospective study of thyroglobulin mRNA detection in neck lymph nodes in patients with suspected differentiated thyroid cancer (DTC) metastases.

MATERIAL

70 nodes from 60 patients with suspected DTC recurrence were investigated. Patients with suspicion of lymph node metastases of other types of cancer were included as a control group. Thyroglobulin RT-PCR was conducted in residual material left after preparation of cytological smears from fine needle biopsy specimens. Primers spanning exons 3-5 were used with 39 cycles of PCR. RNA isolation control and cDNA amplification were carried out using GADPH starters.

RESULTS

Classical cytology confirmed nodal involvement in 22 of DTC patients, RT-PCR Tg was positive in 20 of them (91%). Among 48 patients with a suspicion of DTC recurrence and negative cytology, Tg mRNA was found twice. One positive RT-PCR result was confirmed by repeated cytology conducted 4-6 months later and followed by surgery. No positive result of RT-PCR was obtained with other head and neck malignancies. The overall specificity was estimated with 98%.

CONCLUSIONS

RT-PCR Tg shows sufficient specificity to be applied in further studies estimating its usefulness in fine needle biopsy for early detection of lymph node metastases in differentiated thyroid cancer.

High frequency of recurrent mutations in BRCA1 and BRCA2 genes in Polish families with breast and ovarian cancer

Germ-line mutations in BRCA1 and BRCA2 genes result in a significantly increased risk of breast and ovarian cancer. Other genes involved in an increased predisposition to breast cancer include the TP53 gene, mutated in Li-Fraumeni syndrome. To estimate the frequency of germ-line mutations in these three genes in Upper Silesia, we have analyzed 47 breast/ovarian cancer families from that region. We found five different disease predisposing mutations in 17 (36%) families. Twelve families (25.5%) carried known BRCA1 mutations (5382insC and C61G), four families (8.5%) carried novel BRCA2 mutations (9631delC and 6886delGAAAA), and one family (2%) harbored novel mutation 1095del8 in the TP53 gene, which is the largest germline deletion in coding sequence of this gene identified thus far. The 5382insC mutation in BRCA1 was found in 11 families and the 9631delC mutation in BRCA2 occurred in three families. These two mutations taken together contribute to 82% of all mutations found in this study, and 30% of the families investigated harbor one of these mutations. The very high frequency of common mutations observed in these families can only be compared to that reported for Ashkenazi Jewish, Icelandic, and Russian high-risk families. This frequency, however, may not be representative for the entire Polish population. The observed distribution of mutations will favor routine pre-screening of predisposed families using a simple and cost-effective test.