Minimal and small size invasive breast cancer with no axillary lymph node involvement: the need for tailored adjuvant therapies

Transcriptome analysis reveals differences in cell cycle, growth and migration related genes that distinguish fibroblasts derived from pre-invasive and invasive breast cancer

Background/Introduction

As the most common form of pre-invasive breast cancer, ductal carcinoma in situ (DCIS) affects over 50,000 women in the US annually. Despite standardized treatment involving lumpectomy and radiation therapy, up to 25% of patients with DCIS experience disease recurrence often with invasive ductal carcinoma (IDC), indicating that a subset of patients may be under-treated. As most DCIS cases will not progress to invasion, many patients may experience over-treatment. By understanding the underlying processes associated with DCIS to IDC progression, we can identify new biomarkers to determine which DCIS cases may become invasive and improve treatment for patients. Accumulation of fibroblasts in IDC is associated with disease progression and reduced survival. While fibroblasts have been detected in DCIS, little is understood about their role in DCIS progression.

Goals

We sought to determine 1) whether DCIS fibroblasts were similar or distinct from normal and IDC fibroblasts at the transcriptome level, and 2) the contributions of DCIS fibroblasts to breast cancer progression.

Methods

Fibroblasts underwent transcriptome profiling and pathway analysis. Significant DCIS fibroblast-associated genes were further analyzed in existing breast cancer mRNA databases and through tissue array immunostaining. Using the sub-renal capsule graft model, fibroblasts from normal breast, DCIS and IDC tissues were co-transplanted with DCIS.com breast cancer cells.

Results

Through transcriptome profiling, we found that DCIS fibroblasts were characterized by unique alterations in cell cycle and motility related genes such as PKMYT1, TGF-α, SFRP1 and SFRP2, which predicted increased cell growth and invasion by Ingenuity Pathway Analysis. Immunostaining analysis revealed corresponding increases in expression of stromal derived PKMYT1, TGF-α and corresponding decreases in expression of SFRP1 and SFRP2 in DCIS and IDC tissues. Grafting studies in mice revealed that DCIS fibroblasts enhanced breast cancer growth and invasion associated with arginase-1+ cell recruitment.

Conclusion

DCIS fibroblasts are phenotypically distinct from normal breast and IDC fibroblasts, and play an important role in breast cancer growth, invasion, and recruitment of myeloid cells. These studies provide novel insight into the role of DCIS fibroblasts in breast cancer progression and identify some key biomarkers associated with DCIS progression to IDC, with important clinical implications.

Clinicopathological characteristics, treatments, and prognosis of breast ductal carcinoma in situ with microinvasion: A narrative review

Background

Ductal carcinoma in situ with microinvasion (DCIS-MI) is defined as ductal carcinoma in situ (DCIS) with a microscopic invasive focus ≤1 mm in the longest diameter. The current literature is controversial concerning the clinical prognostic features and management of DCIS-MI. This narrative review described recently reported literature regarding the characteristics, treatment, and prognosis of it.

Methods

Searching PubMed for relevant articles covering the period of 1982 to 2021 using the following terms by MeSH and free-word: breast cancer, microinvasion, DCIS, DCIS-MI, and invasive ductal carcinoma (IDC).

Results

DCIS-MI tends to express more aggressive pathological features such as necrosis, HER2+, ER- or PR-, and high nuclear grade. The overall prognosis of DCIS-MI is typically good, however, some indicators such as young age, HR-, HER2+ and multimicroinvasive lesions, were associated with worse prognoses. And there are also conflicting results on the differences between the prognoses of DCIS-MI and DCIS or T1a-IDC. Postoperative chemotherapy and anti-HER2 therapy still have uncertain benefits and are more likely to be used to treat high-risk patients who are HR- orHER2+ to improve the prognosis.

Conclusion

DCIS-MI has more aggressive pathological features, which may suggest its biological behavior is worse than that of DCIS and similar to early IDC. Although the overall prognosis of DCIS-MI is good, when making decisions about adjuvant therapy clinicians need to give priority to the hormone receptor status, HER2 expression and axillary lymph node status of patients, because these may affect the prognosis and treatment response.

De-escalation of Systemic Therapy for Early-Stage, Node-Negative Her2+ and Triple-Negative Breast Cancer

Purpose of Review

This review summarizes the most recent data on the management of small, node-negative Her2+ and triple-negative breast cancer.

Recent Findings

Both Her2+ and triple-negative breast cancers are characterized by high rates of recurrence and worse survival outcomes compared to hormone-positive cancers. De-escalation of systemic therapy in early-stage breast cancer is a recent national trend in clinical research. Recent prospective trials support the scaling back of cytotoxic agents and maximization of targeted therapy regimens. Similarly, large retrospective studies on small, node-negative triple-negative breast cancer report the omission of chemotherapy in women with T1a,N0 triple-negative cancers with favorable short term outcomes.

Summary

De-escalation of systemic therapy for Her2+ breast cancer is effective in the management of early-stage, node-negative disease. Future prospective studies on the omission of systemic therapy for triple-negative breast cancer are required to safely adopt into consensus guidelines.

Expression of CCL2/CCR2 signaling proteins in breast carcinoma cells is associated with invasive progression

Ductal carcinoma in situ (DCIS) is the most common type of pre-invasive breast cancer diagnosed in women. Because the majority of DCIS cases are unlikely to progress to invasive breast cancer, many women are over-treated for DCIS. By understanding the molecular basis of early stage breast cancer progression, we may identify better prognostic factors and design treatments tailored specifically to the predicted outcome of DCIS. Chemokines are small soluble molecules with complex roles in inflammation and cancer progression. Previously, we demonstrated that CCL2/CCR2 chemokine signaling in breast cancer cell lines regulated growth and invasion through p42/44MAPK and SMAD3 dependent mechanisms. Here, we sought to determine the clinical and functional relevance of CCL2/CCR2 signaling proteins to DCIS progression. Through immunostaining analysis of DCIS and IDC tissues, we show that expression of CCL2, CCR2, phospho-SMAD3 and phospho-p42/44MAPK correlate with IDC. Using PDX models and an immortalized hDCIS.01 breast epithelial cell line, we show that breast epithelial cells with high CCR2 and high CCL2 levels form invasive breast lesions that express phospho-SMAD3 and phospho-p42/44MAPK. These studies demonstrate that increased CCL2/CCR2 signaling in breast tissues is associated with DCIS progression, and could be a signature to predict the likelihood of DCIS progression to IDC.

L1CAM Expression in Recurrent Estrogen Positive/HER2 Negative Breast Cancer: A Novel Biomarker Worth Considering

We investigate L1 cell adhesion molecule (L1CAM) expression in estrogen receptor (ER)-positive/human epidermal growth factor receptor (HER2)-negative breast carcinomas. The finding of a potential correlation between high L1CAM expression and recurrent/metastatic disease in luminal A and B breast carcinomas may be helpful for risk stratification and open opportunities for targeted therapies. 304 cases comprising 152 cases of ER-positive, progesterone receptor (PR)-positive/negative, and HER2-negative recurrent/metastatic breast carcinomas and 152 nonrecurrent controls were included. ER, PR, HER-2, Ki-67 status, Nottingham grade, tumor size, tumor stage, number of foci, lymph node status, lymphovascular invasion, phenotype, laterality, age at diagnosis and first distant or local recurrence were recorded. L1CAM positive cases showed increased specificity for recurrence and these patients were significantly younger than L1CAM negative ones. Compared with L1CAM negative recurrent cases, L1CAM positive ones had a noticeably higher Ki-67, tended to be larger and recurred sooner. All L1CAM positive recurrent/metastatic cases were of the luminal B subtype compared with 67.3% of the L1CAM negative cases. L1CAM is highly specific for recurrence in a subset of breast cancer patients and may be associated with more aggressive behavior, particularly in luminal B breast cancers with higher Ki-67 expression. Further investigation about the prognostic value of L1CAM is warranted.

Characteristics and clinical outcome of pT1a-b node-negative breast cancer

OBJECTIVE:

Tumor size, along with other clinicopathological characteristics, has a prognostic role in breast cancer. Recurrence risk tends to rise as tumor size increases. Early T-stage portends a good prognosis. We aimed to investigate the recurrence-free interval rates of T1abN0 group of early breast cancer.

METHODS:

Patients diagnosed with pT1a and T1b, lymph node metastasis-negative breast cancer were included in the study. Clinicopathologic characteristics including recurrence, distant metastasis, and final status of the patients were obtained retrospectively from the patient files.

RESULTS:

A total of 84 patients included. Twenty-six patients (31%) had T1a and 58 patients (69%) had T1b tumors. The 5-year distant relapse-free survival (DRFS) rate of T1ab tumors was 95.2%. The DRFS rate of T1a tumors was 96.2%, while the rate of T1b tumors was 94.8% (p=0.555). The 5-year RFS rate of T1ab tumors was 90.5%. The RFS rate of T1a tumors was 84.6%, whereas the rate of T1b tumors was 93.1% (p=0.359). The 5-year DRFS rate of hormone receptor positive group was 97%, Her-2 positive group was 81.8%, and triple negative group was 100% (p=0.041). The 5-year RFS rate of the hormone receptor positive group was 97%, Her-2 positive group was 72.7%, and triple negative group was 57.1% (p=0.001).

CONCLUSION:

The results of the study provided that both T1a and T1b tumors have a good and similar prognosis.

Do 21-Gene Recurrence Score Influence Chemotherapy Decisions in T1bN0 Breast Cancer Patients?

Purpose: Hormone receptor (HR)-positive breast cancer patients with tumor size ≤1.0 cm and negative node have favorable outcomes. The 21-gene Recurrence Score (RS) could predict response to chemotherapy for HR+ breast cancer, but its role in T1bN0 disease is challenging.

Methods: T1bN0 breast cancer patients diagnosed between January 2014 and June 2019 with RS results were included and categorized as Low- (RS < 18), Intermediate- (RS 18–30), or High-risk (RS > 30) groups. Univariate and multivariate analysis were used to assess factors associated with RS distribution and chemotherapy recommendation. Chemotherapy decisions change and patient adherence after 21-gene RS testing were also evaluated.

Results: Among 237 patients with T1bN0 tumors, proportions of Low-, Intermediate-, and High-risk RS were 19.8, 63.3, and 16.9%, respectively. Multivariate analysis found that ER expression (P = 0.011), PR expression (P < 0.001), and Ki-67 index (P = 0.001) were independently associated with RS distribution. Adjuvant chemotherapy was recommended for 31.6% of patients, which was more frequently given to patients with higher tumor grade [Odds ratio (OR) = 2.99 for grade II, OR = 59.19 for grade III, P = 0.006], lymph vascular invasion (OR = 8.22, P = 0.032), Luminal-B subtype (OR = 5.68, P < 0.001), and Intermediate-to High-risk RS (OR = 10.01 for Intermediate-risk, OR = 192.42 for High-risk, P < 0.001). Chemotherapy decision change was found in 18.6% of patients, mainly in those with Intermediate- to High-risk RS tumor with the majority from no-chemotherapy to chemotherapy. The treatment compliance rate after the 21-gene RS testing with MDT was 95.4%.

Conclusion: RS category was related to ER, PR, and Ki-67 expression, which was recognized as an independent factor of chemotherapy recommendation in T1bN0 breast cancer. The 21-gene RS testing would lead to a chemotherapy decision change rate of 18.6% as well as a high treatment adherence, which can be applied in T1bN0 patients.

Studies on DNA Damage Repair and Precision Radiotherapy for Breast Cancer

Radiotherapy acts as an important component of breast cancer management, which significantly decreases local recurrence in patients treated with conservative surgery or with radical mastectomy. On the foundation of technological innovation of radiotherapy setting, precision radiotherapy of cancer has been widely applied in recent years. DNA damage and its repair mechanism are the vital factors which lead to the formation of tumor. Moreover, the status of DNA damage repair in cancer cells has been shown to influence patient response to the therapy, including radiotherapy. Some genes can affect the radiosensitivity of tumor cell by regulating the DNA damage repair pathway. This chapter will describe the potential application of DNA damage repair in precision radiotherapy of breast cancer.

Identification of miRNAs as biomarkers for acquired endocrine resistance in breast cancer

Therapies targeting estrogen receptor α (ERα) including tamoxifen, a selective estrogen receptor modulator (SERM) and aromatase inhibitors (AI), e.g., letrozole, have proven successful in reducing the death rate for breast cancer patients whose initial tumors express ERα. However, about 40% of patients develop acquired resistance to these endocrine treatments. There is a critical need to develop sensitive circulating biomarkers that accurately identify signaling pathways altered in breast cancer patients resistant to endocrine therapies. Serum miRNAs have the potential to serve as biomarkers of the progression of endocrine-resistant breast cancer due to their cancer-specific expression and stability. Exosomal transfer of miRNAs has been implicated in metastasis and endocrine-resistance. This review focuses on miRNAs in breast tumors and in serum, including exosomes, from breast cancer patients that are associated with resistance to tamoxifen since it is best-studied.

Evaluation of the Quality of Adjuvant Endocrine Therapy Delivery for Breast Cancer Care in the United States

Importance

Randomized trials in breast cancer have demonstrated the clinical benefits of adjuvant endocrine therapy (AET) in preventing recurrence and death. The examination of concordance with AET guidelines at a national level as a measure of quality of care is important.

Objective

To investigate temporal trends and factors related to receipt of AET for breast cancer.

Design, Setting, and Participants

This retrospective cohort study included 981 729 women with breast cancer in the National Cancer Database from January 1, 2004, to December 31, 2013. Women with stages I to III breast cancer who received all or part of their treatment at the reporting institution were included in the analysis.

Main Outcomes and Measures

Temporal changes in AET receipt (estimating the annual percentage change) and AET practice patterns (using logistic regression) and the effect of AET guideline concordance on survival of women with hormone receptor-positive (HR+) breast cancer (using the multivariable Cox proportional hazards model).

Results

Of the 981 729 eligible patients (mean [SD] age, 60.8 [13.3] years), 818 435 had HR+ and 163 294 had HR-negative (HR-) cancer. Among the patients with HR+ cancer, receipt of AET increased over time, from 69.8% in 2004 to 82.4% in 2013. Among patients with HR- cancer, receipt decreased from 5.2% in 2004 to 3.4% in 2013. Hospital-level adherence (≥80% of patients with HR+ cancer received AET) increased from 40.2% in 2004 to 69.2% in 2013. Receipt of AET varied significantly by age (lower in patients ≥80 years), race (lower in African American and Hispanic participants), geographic location (lower in West South Central, Mountain, and Pacific census regions), and receptor status (lower in patients with estrogen receptor-negative and progesterone receptor-positive cancer). Surgery and radiotherapy were the factors most significantly associated with appropriate AET receipt (only 45.0% in patients who received lumpectomy without radiotherapy). Receipt of AET was associated with a 29% relative risk reduction in mortality. Based on this effectiveness estimate, if all patients with HR+ cancer received AET, approximately 14 630 lives would have been saved over 10 years.

Conclusions and Relevance

From 2004 to 2013, underuse and misuse of AET have decreased for patients with breast cancer, but optimal use has not been achieved, and significant variation in care remains. The involvement of surgery and radiotherapy were among the most significant factors associated with optimal use, which underscores the benefits of team-based care to support guideline-concordant therapy.

Ki67 Frequency in Breast Cancers without Axillary Lymph Node Involvement and its Relation with Disease-free Survival

BACKGROUND

Breast cancer prognosis is influenced by several histopathology and clinical factors including expression of Ki67 which may have a predictive role in lymph node negative breast cancer patients. The aim of this study was to assess Ki67 expression in breast cancers without axillary lymph node involvement and to evaluate its prognostic value with regard to disease-free survival.

MATERIALS AND METHODS

Subjects were selected from non-metastatic invasive breast cancer patients who were referred to the oncology department of Ghaem hospital during 1 April 2001 to 1 April 2008. Ki67 levels were measured using immunohistochemistry (IHC) and compared with clinicopathological features. The relation of Ki67 expression with disease-free survival was also analysed.

RESULTS

A total of 106 women with a mean age of 49 were examined. Some 94.3% were classified as having invasive ductal carcinomas and the mean tumour diameter at the time of diagnosis was 2.8 cm. Some 50.9% of cases were ER positive and 47.2% were PR positive. P53 expression was positive in 48.1% of the cases. According to the IHC results, only 8.5% of the patients were Her2/neu positive. Ki67 was positive in 66 (62.3%) with a significant relation to lower age (p=0.0229) and P53 positivity (p=0.005). After an average of 40-months follow up, 13 (12.3%) demonstrated recurrence, most commonly systemic. Of 13 cases with relapse, 10 patients (77%) were Ki67 positive.

CONCLUSIONS

In our population Ki67 appeared to be an independent prognostic factor for three-year survival. However, we stress that a survival study with a bigger sample size would help to support this conclusion.

Daily Practice Management of pT1a-b pN0 Breast Carcinoma: A Prospective French ODISSEE Cohort Study

BACKGROUND

Most breast cancer (BC) tumors ≤10 mm have an excellent prognosis. The subgroups with a higher risk for distant recurrence requiring adjuvant systemic therapy are not precisely defined in current international guidelines.

PATIENTS AND METHODS

The OBSERVATOIRE DES PETITS CANCERS DU SEIN HER2 +/- (ODISSEE) study was a prospective, multicenter, cohort study that aimed to describe the daily adjuvant management and outcome of 616 patients with unifocal, invasive pT1a-b pN0 nonmetastatic BC who underwent surgery.

RESULTS

At the time of diagnosis, the median age of patients was 61 years. Tumor was detected on imaging or during a screening program in 397 patients (64.6%). Most patients (96%) underwent conservative surgery with sentinel node biopsy (89%), completed with axillary lymph node dissection in 15%. At inclusion, 82% of tumors were pT1b, 73% were pN0 (i-), 53% were Scarff-Bloom-Richardson Grade I, 91% were estrogen receptor (ER)-positive, 5% overexpressed/amplified HER2, and 5% were triple negative (TNBC). Adjuvant treatments were radiotherapy (95%), hormone therapy (82%), chemotherapy (7%), and trastuzumab (3.5%). In patients with TNBC and HER2-positive BC, chemotherapy and trastuzumab (if needed) were administered in 45% and 68%, respectively. After 5 years of follow-up, 7 patients had contralateral BC, 7 had locoregional recurrence, and 1 had distant metastasis. At 5 years, overall survival, disease-free survival, and recurrence-free survival were: 98.4% (96.9%-99.1%), 94.7% (92.4%-96.3%), and 97.1% (95.2%-98.2%), respectively.

CONCLUSION

This prospective cohort study showed that in France, the routine practice in pT1a-b pN0 breast cancers follows international standard guidelines for practice including conservative surgery followed by radiotherapy and endocrine therapy for ER-positive patients. Adjuvant chemotherapy with or without trastuzumab was used but their benefit in breast cancer of ≤10 mm remains controversial.

Is adjuvant chemotherapy necessary for patients with microinvasive breast cancer after surgery?

Objective: Survival and treatment of patients with microinvasive breast cancer (MIBC) remain controversial. In this paper, we evaluated whether adjuvant chemotherapy is necessary for patients with MIBC to identify risk factors influencing its prognosis and decide the indication for adjuvant chemotherapy. Methods: In this retrospective study, 108 patients with MIBC were recruited according to seventh edition of the staging manual of the American Joint Committee on Cancer (AJCC). The subjects were divided into chemotherapy and non-chemotherapy groups. We compared the 5-year disease-free survival (DFS) and overall survival (OS) rates between groups. Furthermore, we analyzed the factors related to prognosis for patients with MIBC using univariate and multivariate analyses. We also evaluated the impact of adjuvant chemotherapy on the prognostic factors by subgroup analysis after median follow-up time of 33 months (13-104 months). Results: The 5-year DFS and OS rates for the chemotherapy group were 93.7% and 97.5%, whereas those for the non-chemotherapy group were 89.7% and 100%. Results indicate that 5-year DFS was superior, but OS was inferior, in the former group compared with the latter group. However, no statistical significance was observed in the 5-year DFS (P=0.223) or OS (P=0.530) rate of the two groups. Most relevant poor-prognostic factors were Ki-67 overexpression and negative hormonal receptors. Cumulative survival was 98.2% vs. 86.5% between low Ki-67 (≤20%) and high Ki-67 (>20%). The hazard ratio of patients with high Ki-67 was 16.585 [95% confidence interval (CI), 1.969-139.724; P=0.010]. Meanwhile, ER(-)/PR(-) patients with MIBC had cumulative survival of 79.3% compared with 97.5% for ER(+) or PR(+) patients with MIBC. The hazard ratio for ER(-)/PR(-) patients with MIBC was 19.149 (95% CI, 3.702-99.057; P<0.001). Subgroup analysis showed that chemotherapy could improve the outcomes of ER(-)/PR(-) patients (P=0.014), but not those who overexpress Ki-67 (P=0.105). Conclusions: Patients with MIBC who overexpress Ki-67 and with negative hormonal receptors have relatively substantial risk of relapse within the first five years after surgery. However, adjuvant chemotherapy can only improve the outcomes of ER(-)/PR(-) patients, but not those who overexpress Ki-67. Further studies with prolonged follow-up of large cohorts are recommended to assess the prognostic significance and treatment of this lesion.

How to identify patients with increased risk of breast cancer relapse?

A cohort of 362 breast cancer patients had subtype classification accomplished using 4 immunohistochemical markers: luminal A (ER or PR positive, HER2 negative, Ki-67<14%), luminal B (ER or PR positive, HER2 negative, Ki-67≥14%), luminal HER2 (ER or PR positive, HER2 positive), HER2 enriched (ER or PR negative, HER2 positive) or triple negative (ER, PR, and HER2 negative). Multivariable Cox analysis was used to determine the risk of local (LR) or distant (DR) relapse associated with the intrinsic subtypes, adjusting for standard clinicopathologic factors. There have been a total of 124 recurrences. Triple-negative patients were associated with increased risk of LR. Luminal B subtype showed statistical tendency (P=0.053) to LR. For patients undergoing breast conservation surgery, luminal B and HER2-enriched subtypes demonstrated an increased risk to LR, and this was statistically significant on multivariable analysis. After mastectomy, there was no statistical difference between subtypes of LR or DR on multivariable analysis. Luminal A tumors are associated with a low risk of LR or DR. Despite the existence of gene expression profiling, in the current study we demonstrate that analysis of 4 immunohistochemical markers is equally effective and less expensive alternative to identify higher recurrence risk patients.

Proportion and clinical outcomes of postoperative radiotherapy omission after breast-conserving surgery in women with breast cancer

PURPOSE

The present study was conducted to investigate the proportion and clinical outcomes of breast cancer patients who did not receive postoperative radiotherapy (PORT) after breast-conserving surgery (BCS).

METHODS

This retrospective study included all breast cancer patients received curative BCS without PORT between 2003 and 2013. In the PORT omission group, characteristics and local recurrence differences were compared between the recommended group and the refused group. To compare the local recurrence-free survival (LRFS) of the PORT omission group and the control group who received PORT, subjects were selected by using the pooled data of patients treated between 1994 and 2007.

RESULTS

During the study period, 96 patients did not receive PORT among a total of 6,680 patients who underwent BCS. Therefore, the overall rate of PORT omission was 1.4%. Among the 96 patients, 20 were recommended for PORT omission (recommended group) and 76 refused PORT (refused group). The median follow-up period of all study participants was 19.3 months (range, 0.3-115.1 months). Patients in the recommended group were older (p=0.004), were more likely to be postmenopausal (p=0.013), and had more number of positive prognostic factors compared with the refused group. Overall, 12 cases of disease recurrence, including 11 cases of local recurrence, developed in the PORT-refused group. The LRFS of the PORT-omission group was significantly inferior to that of patients who received PORT after BCS (p<0.001). In the PORT-omission group, significant favorable prognostic factors for LRFS were having histologic grade 1 or 2 disease (p=0.023), having no axillary lymph node metastasis (p=0.039), receiving adjuvant endocrine therapy (p=0.046), and being in the recommended group (p=0.026).

CONCLUSION

The rate of PORT omission in the present study is very low among women who underwent surgery compared to that of other studies worldwide. PORT omission is significantly related to a high local recurrence rate.

Endocrine sensitivity is decisive for patient outcome in small node-negative breast cancers (BC) (pT1a,b) - results from the Munich Cancer Registry

PURPOSE

In clinical routine, adjuvant systemic therapy in small node-negative (N0) BC is controversial, in particular in HER2-positive disease. We aimed to evaluate outcome of consecutive patients with small N0 BC in a population-based cancer registry and thus consequently substantiate indications for chemotherapy in those patient subgroups at increased relapse risk or poor survival.

METHODS

From 2002 to 2009 (median follow-up 6 years), 9707 primary breast cancer patients with N0 tumors <2 cm (pTis, pT1N0M0) were reported to the Munich Cancer Registry. Patients with pTis tumors (n = 1870) served as internal comparator. Time to progression, observed (OS) and relative survival rates (Kaplan-Meier estimates) are presented. Cox regression analysis was used to assess the influence of tumor size, age, HR-, and HER2-status.

RESULTS

10-year-OS for pTis was 94.0%. In HR-positive tumors it was 91.9% in pT1a, 90.6% in pT1b, and 86.8% in pT1c. In HR-negative tumors, rates were 91.7%, 86.8%, and 86.8%, respectively. In HER2-positive tumors it was 81.2%, 88.1%, and 86.7%, in HER2-negative 93.1%, 90.6%, and 86.0%, respectively. In the multivariate model, age, tumor size, and HR-status showed a significant impact on OS (HRneg. vs. HRpos.: hazard ratio 1.50 (95% CI; 1.12-1.99), while HER2-status was not an independent prognostic factor.

CONCLUSION

Prognosis of N0 tumors <1 cm is excellent, especially if they are HR-positive, even in HER2-positive cases. Weighing potential benefits vs. side-effects, there seems to be no need for chemotherapy in tumors <0.5 cm. In pT1b chemotherapy may be considered, if tumors are triple negative or HER2-positive and HR-negative. In pT1c guideline-based adjuvant therapy using all therapeutic options seems to be warranted.

Human epidermal growth factor receptor 2-positive microinvasive breast carcinoma with a highly aggressive course: a case report

Background

Microinvasive ductal carcinoma in situ of the breast is a rare entity defined as ductal carcinoma in situ with invasive foci measuring no more than 1 mm. In general, the outcome is excellent, similar to ductal carcinoma in situ. We report a patient with breast ductal carcinoma in situ with microinvasion who died eight months after diagnosis due to progression of the disease – liver metastases. This is the first report in the literature of such an aggressive course.

Case presentation

A 47-year-old Caucasian woman presented with mammographic-detected suspicious microcalcinations in an area of 8.6 x 6 cm. A radical mastectomy with a sentinel lymph node biopsy and immediate breast reconstruction with implant was performed. A histopathological report showed a massive high grade ductal carcinoma in situ, of the solid and comedo type. In one quadrant, some foci of microinvasions of less than 1 mm were present. Tumour margins were free. Isolated tumour cells were found in the sentinel lymph node. Hormone receptors were negative and human epidermal growth factor receptor-2 status was not performed. The patient received no adjuvant systemic therapy. Eight months after the surgery, she died from hepatic failure without known breast cancer progression before. An autopsy revealed diffuse liver metastases with human epidermal growth factor receptor 2-positive, hormone receptor negative breast cancer. Dissemination to other organs was not proven.

Conclusion

Our patient is a rare case of ductal carcinoma in situ with microinvasion that developed distant metastases very early. In case of multiple foci of microinvasion, besides radical local treatment we suggest considering adjuvant systemic treatment based on biological characteristics since tumour size alone does not predict the prognosis well.

Relationship between chemotherapy and prognosis in different subtypes of node-negative breast cancer

Knowledge is limited about the relationship between chemotherapy and prognosis among the subtypes of axillary node-negative breast cancer (ANNBC). In this study, a population including 2,236 primary and operable ANNBC patients, with a median age of 53, were included. All breast tumors were classified into five immunohistochemically defined subtypes-luminal A, luminal B, luminal human epidermal growth factor receptor 2 (HER2), HER2 overexpression, and triple negative. With a median follow-up of 73.6 months, the rate of relapse was lowest in luminal A (6.5 %) and highest in HER2 overexpression subtype (16.4 %). Multivariate analysis indicated that the risks of relapse and death were enhanced in HER2 overexpression and triple-negative (TN) subtypes, and these two subtypes were independent predictors of relapse and death. Luminal A patients with risk factors could benefit from chemotherapy in terms of relapse-free survival (RFS). The relapse rate of TN patients after chemotherapy with taxanes was lower compared with that after chemotherapy without taxanes. In conclusion, women with ANNBC were at higher risks of relapse and death if suffering from HER2 overexpression or TN diseases. Chemotherapy could reduce the recurrence rate of luminal A patients with risk factors. TN patients may benefit from adjuvant chemotherapy containing taxanes.

HER2 overexpression a major risk factor for recurrence in pT1a-bN0M0 breast cancer: results from a French regional cohort

The management of pT1a-bN0M0 breast cancer remains an area of controversy. Data from 714 patients classified as having pT1a-bN0M0 breast cancer and treated, from 1999 to 2004 in the Languedoc-Roussillon France, were analyzed. The human epidermal growth factor receptor 2 (HER2) status analyses were centralized. The objective of this study was to describe the prognosis of pT1a-bN0M0 breast cancer according to HER2 distribution and hormonal status. The median follow-up was 6.4 years. Ten-year overall survival was 94%. HER2 overexpression was observed in 6.1% of the patients. The 10-year prognosis of patients with HER2-positive tumors was worse than that of those with HER2-negative (disease-free survival 73% vs. 89%, P < 0.0001). Tumor size (T1a/T1b) was not a relevant prognostic factor. The co-expression of HER2 with hormonal receptors (HR) was associated with high recurrence at 10 years. In both univariate and multivariate analyses, the most relevant prognostic factor for this population was HER2 amplification. In multivariate analysis, patients with HER2-positive tumors had higher risk of mortality (HR, 3.89; 95% CI, 1.58–9.56). In pT1a-bN0M0 breast cancers, HER2 amplification or overexpression is a risk factor for recurrence. In HER2-positive breast cancers, HR expression is associated with a poor prognosis despite the hormone therapy. For this population, a personalized management may be required.

Association of HER2 Overexpression and Prognosis in Small (T1N0) Primary Breast Cancers

BACKGROUND

There is some controversy regarding the precise role and need for adjuvant therapy in patients with pT1a/pT1bN0 breast cancer, although studies have indicated that a HER2-positive status is one of the most powerful poor prognostic factors.

PATIENTS AND METHODS

We retrospectively evaluated disease-free survival (DFS), distant disease-free survival (DDFS), and overall survival (OS) among 960 patients diagnosed between 2000 and 2008 with T1N0 primary breast cancer treated at 3 German centers, and determined prognostic risk factors. Univariate analysis was used to determine associations with potential risk factors.

RESULTS

With a median follow-up of 23 months, DFS was 94.8%, DDFS 96.3%, and OS 97.5%. Risk factors for decreased 1-year DFS were: peritumoral lymphatic invasion (L1) (p = 0.031), negative hormone receptor status (p = 0.003), non-use of hormonal therapy (p = 0.001), and a positive HER2 status (p = 0.003). Amongst the HER2-positive patients only 2.7% (n = 1/37) of those treated with trastuzumab had a DFS event compared with 20% (n = 10/50) without trastuzumab.

CONCLUSION

Patients with HER2-positive T1 breast cancer should be considered for inclusion in prospective trials of trastuzumab in combination with chemotherapy to determine the risk-to-benefit ratio and association with other prognostic factors.

The CIN4 chromosomal instability qPCR classifier defines tumor aneuploidy and stratifies outcome in grade 2 breast cancer

Purpose

Quantifying chromosomal instability (CIN) has both prognostic and predictive clinical utility in breast cancer. In order to establish a robust and clinically applicable gene expression-based measure of CIN, we assessed the ability of four qPCR quantified genes selected from the 70-gene Chromosomal Instability (CIN70) expression signature to stratify outcome in patients with grade 2 breast cancer.

Methods

AURKA, FOXM1, TOP2A and TPX2 (CIN4), were selected from the CIN70 signature due to their high level of correlation with histological grade and mean CIN70 signature expression in silico. We assessed the ability of CIN4 to stratify outcome in an independent cohort of patients diagnosed between 1999 and 2002. 185 formalin-fixed, paraffin-embedded (FFPE) samples were included in the qPCR measurement of CIN4 expression. In parallel, ploidy status of tumors was assessed by flow cytometry. We investigated whether the categorical CIN4 score derived from the CIN4 signature was correlated with recurrence-free survival (RFS) and ploidy status in this cohort.

Results

We observed a significant association of tumor proliferation, defined by Ki67 and mitotic index (MI), with both CIN4 expression and aneuploidy. The CIN4 score stratified grade 2 carcinomas into good and poor prognostic cohorts (mean RFS: 83.8±4.9 and 69.4±8.2 months, respectively, p = 0.016) and its predictive power was confirmed by multivariate analysis outperforming MI and Ki67 expression.

Conclusions

The first clinically applicable qPCR derived measure of tumor aneuploidy from FFPE tissue, stratifies grade 2 tumors into good and poor prognosis groups.

Recurrence risk in small, node-negative, early breast cancer: a multicenter retrospective analysis

PURPOSE

Recurrences and deaths are known to occur, even if less frequently, in small, node-negative breast cancer patients, and decision on adjuvant treatments remains controversial. In the present analysis, we evaluate recurrence risk in patients with pT1 a, b, c, node-negative, breast cancer, accordingly with some prognostic biological factors.

METHODS

We retrospectively evaluated 900 node-negative patients (pT1a, b, c) surgery treated between 2000 and 2009 in four Italian oncologic centers. We defined 3 different cohorts: ER positive (ER+); Her-2 positive (Her-2+); and triple negative (TN).

RESULTS

pT1a was seen in 7.6% of patients, 37.7 % pT1b, 54.8 % pT1c. Concerning the 3 different cohorts, 58.2 % were ER+; 10.8 % were Her-2+; 8.2 % were TN. Overall, chemotherapy was given to 3.0 %, 27.2 %, 69.8 % of pT1a, b, c, respectively, and to 22.7 %, 58.8 %, 68.9 % of ER+, Her-2+, TN subgroups. At a median follow-up of 67 months, 5-year DFS was 96.3 %, 89.2 %, 89.4 % in pT1a, b, c, respectively (100 %, 93.6 %, 89.8 % in ER+; 100 %, 78.7 %, 85.0 % in Her-2+; 100 %, 76.8 %, 85.2 % in TN) (p = ns). At multivariate analysis, histologic grade and Ki-67 resulted independent prognostic factors. Overall, 5-year OS was 98 %, without differences among pT1a, b, c, or among the 3 cohorts.

CONCLUSIONS

Overall, 5-year DFS was very favorable in this series of small, node-negative breast cancers, but Her-2+ and TN cohorts have a higher recurrence rate than ER+ cohort (p < 0.0001); pT1c, but also pT1b, in Her-2+ and TN subgroups, have a worse outcome, and effective chemotherapy treatment should be considered in these unfavorable subgroups.

Adjuvant chemotherapy of pT1a and pT1b breast carcinoma: results from the NEMESI study

BACKGROUND

The prognosis of pT1a-pT1b breast cancer (BC) used to be considered very good, with a 10-y RFS of 90%. However, some retrospective studies reported a 10-y RFS of 81%-86% and suggested benefit from adjuvant systemic therapy.

METHODS

To evaluate the variables that determined the choice of adjuvant chemotherapy and the type of chemotherapy delivered in pT1a-pT1b BC, we analysed the small tumours enrolled in the NEMESI study.

RESULTS

Out of 1,894 patients with pathological stage I-II BC enrolled in NEMESI, 402 (21.2%) were pT1a-pT1b. Adjuvant chemotherapy was delivered in 127/402 (31.59%). Younger age, grading G3, high proliferative index, ER-negative and HER2-positive status were significantly associated with the decision to administer adjuvant chemotherapy. An anthracycline without taxane regimen was administered in 59.1% of patients, anthracycline with taxane in 24.4%, a CMF-like regimen in 14.2% and taxane in 2.4%. Adjuvant chemotherapy was administered in 88.4% triple-negative and 73.46% HER2-positive pT1a-pT1b BC. Adjuvant trastuzumab was delivered in 30/49 HER2-positive BC (61.2%).

CONCLUSIONS

Adjuvant chemotherapy was delivered in 31.59% T1a-pT1b BC treated at 63 Italian oncological centres from January 2008 to June 2008. The choice to deliver chemotherapy was based on biological prognostic factors. Anthracycline-based chemotherapy was administered in 83.5% patients.

Management of Small T1a/b N0 Breast Cancers

T1ab N0 breast cancer generally has excellent prognosis. Adverse prognostic factors include HER2+ disease, ER-negative disease, high-grade histology, T1b, and young age of patient. These patients are largely excluded from most trials, and to date, no prospective studies for this group yet reported. Treatment guidelines are vague and treatment inconsistent. As yet, in the HER2+ population, little experience with targeted therapy has been reported. Prospective trials are needed.

Identification of a claudin-4 and E-cadherin score to predict prognosis in breast cancer

The elevated expression of claudins (CLDN) and E-cadherin (CDH-1) was found to correlate with poor prognostic features. Our aim was to perform a comprehensive analysis to assess their potential to predict prognosis in breast cancer. The expression of CLDN-1, -3-5, -7, -8, -10, -15, -18, and E-cadherin at the mRNA level was evaluated in correlation with survival in datasets containing expression measurements of 1809 breast cancer patients. The breast cancer tissues of 197 patients were evaluated with tissue microarray technique and immunohistochemical method for CLDN-1-5, -7, and E-cadherin protein expression. An additional validation set of 387 patients was used to test the accuracy of the resulting prognostic score. Based on the bioinformatic screening of publicly-available datasets, the metagene of CLDN-3, -4, -7, and E-cadherin was shown to have the most powerful predictive power in the survival analyses. An immunohistochemical protein profile consisting of CLDN-2, -4, and E-cadherin was able to predict outcome in the most effective manner in the training set. Combining the overlapping members of the above two methods resulted in the claudin-4 and E-cadherin score (CURIO), which was able to accurately predict relapse-free survival in the validation cohort (P = 0.029). The multivariate analysis, including clinicopathological variables and the CURIO, showed that the latter kept its predictive power (P = 0.040). Furthermore, the CURIO was able to further refine prognosis, separating good versus poor prognosis subgroups in luminal A, luminal B, and triple-negative breast cancer intrinsic subtypes. In breast cancer, the CURIO provides additional prognostic information besides the routinely utilized diagnostic approaches and factors.

Ki 67 is a major, but not the sole determinant of Oncotype Dx recurrence score

Background:

Immunohistological assessment of Ki 67 expression is less expensive than Oncotype Dx, which is currently used to identify patients with lymph node-negative breast cancer, who will benefit from adjuvant chemotherapy.

Methods:

The relationship of immunohistologically measured Ki 67 to Oncotype DX recurrence score (RS) was examined in 53 cases of T1–2 N0 M0 (oestrogen receptor-positive, HER2/neu negative) breast cancer.

Results:

There was a strong linear correlation between Ki 67 value and the Oncotype Dx RS. All patients in the low Ki 67 group (Ki 67 of ⩽10%) had Oncotype Dx RSs of low or intermediate risk. The vast majority of patients (93.8%) in the high-Ki 67 group (Ki 67⩾25%) had oncotype RSs of high or intermediate risk.

Conclusion:

Ki 67 proliferation value is a major, but not the sole determinant of Oncotype Dx score.

Age and associated fibrocystic changes are prognostically significant in patients with small node-negative (T1a,bN0) invasive breast cancer

Some patients with small (≤1.0 cm) node-negative (T1a,bN0) invasive breast cancer (IBC) who undergo only local therapy experience recurrences. There is limited information on prognostic factors in these patients. We sought to identify prognostic factors associated with disease-free survival (DFS) and overall survival (OS) in patients with T1a,bN0 IBC. Histologic sections from 273 T1a,bN0 IBC patients treated at M. D. Anderson Cancer Center (MDACC) between 1980 and 1999 were reviewed. Microscopic tumor size; multifocality; histologic type, grade of tumor; presence, type, grade of associated ductal carcinoma in situ (DCIS); presence of fibrocystic changes (FCC) with/without atypia; and lymphovascular invasion were identified. The Kaplan-Meier method was used to evaluate DFS and OS. Median patient age was 58 years, median follow-up period was 10.8 years, and median tumor size was 0.8 cm. Multifocal disease was identified in 26% of cases. At 10 years, the DFS and OS rates were 91% and 88%, respectively. Twenty-one percent of patients had extensive (>50%), and 30% had grade 3 DCIS. Nonproliferative FCC and proliferative FCC with/without atypia were present in 80%, 36%, and 38% of patients, respectively. In univariate analysis, age at diagnosis (p < 0.0001), grade (p = 0.015), and percent (p = 0.046) of DCIS were significantly associated with DFS; presence of FCC was associated with longer DFS and OS. In multivariable models, age and presence of FCC remained significantly associated with survival. Age at diagnosis and associated FCC are significant factors in predicting recurrence in patients with T1a,bN0 IBC. Adjuvant systemic therapy should be discussed with and considered for young patients with T1a,bN0 IBC.

Young age is associated with ipsilateral breast tumor recurrence after breast conserving surgery and radiation therapy in patients with HER2-positive/ER-negative subtype

Young breast cancer patients are more likely than old patients to experience ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery (BCS). However, the pathological processes underlying this relationship have not been elucidated. We investigated the effect of young age on IBTR in a Korean cohort of women with different molecular subtypes of breast cancer. We analyzed data of 2,102 consecutive breast cancer patients who underwent BCS and post-surgical radiation therapy (RT) at two Korean institutions between 2000 and 2005. Patients were classified as young (≤ 40 years; N = 513) or old (> 40 years; N = 1,589). Breast cancer subtype was determined by estrogen receptor (ER), progesterone receptor (PR), and HER2. Median follow-up duration was 61 months. The 5-year IBTR rate was 3.4% in young patients and 1.1% in old patients (P < 0.001). Univariate analysis indicated that IBTR rate in young patients with luminal A and HER2 subtypes was significantly greater than in old patients with these subtypes (P = 0.015 and P < 0.001, respectively). Multivariate analysis, which used luminal A subtype in old patients as reference, indicated that HER2 subtype in young patients was associated with increased risk of IBTR (hazard ratio, HR = 12.24; 95% CI: 2.54-57.96). Among old patients, HER2 subtype was not associated with increased IBTR. In conclusion, young women had a higher rate of IBTR after BCS and RT than old women. This difference is mainly among women with HER2 subtype. Aggressive local control and adjuvant therapy should be considered for young women with HER2 subtype breast cancer.

A retrospective study of breast cancer subtypes: the risk of relapse and the relations with treatments

Immunohistochemical markers are often used to classify breast cancer into subtypes that are biologically distinct and behave differently. The aim of this study was to estimate relapse for patients with the major subtypes of breast cancer as classified using immunohistochemical assay and to investigate the patterns of benefit from the therapies over the past years. The study population included primary, operable 2,118 breast cancer patients, all non-specific infiltrative ductal carcinoma, with the median age of 53.2 years. All patients underwent local and/or systemic treatments. The clinicopathological characteristics and clinical outcomes were retrospectively reviewed. The expression of estrogen receptor (ER), progesterone receptor, human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR), and cytokeratin 5/6 were analyzed by immunohistochemistry. All patients were classified into the following categories: luminal A, luminal B, HER2 overexpressing, basal-like, and unclassified subtypes. Ki-67 was detected in luminal A subtype. The median follow-up time was 67.9 months. Luminal A tumors had the lowest rate of relapse (12.7%, P < 0.001), while luminal B, HER2 overexpression, and basal-like subtypes were associated with an increased risk of relapse (15.7, 19.1, 20.9%). Molecular subtypes retained independent prognostic significance (P < 0.001). In luminal A subtype, adjunctive radiotherapy could decrease the risk of relapse (P = 0.005), Ki67 positive was a high-risk factor for relapse (P < 0.001), and adjuvant chemotherapies could reduce the relapse for the patients with risk factors (P < 0.001). Adjuvant hormone therapy was an effective treatment for ER-positive tumors (P < 0.001). Molecular subtypes of breast cancer could robustly identify the risk of recurrence and were significant in therapeutic decision making. The model combined subtype and clinical pathology was a significant improvement. Luminal A tumors might represent two distinct subsets which demonstrated distinct prognosis and therapy response.

Management of small HER2-positive breast cancers

Trastuzumab has revolutionised the treatment of HER2-positive early-stage breast cancer and is now standard of care in combination with chemotherapy for patients with tumours larger than 1 cm. However, 5 years after publication of the landmark trials establishing the efficacy of the drug, the management of small (≤1 cm), HER2-positive tumours remains difficult. Most small breast cancers have a good prognosis and adjuvant chemotherapy is not routinely recommended. However, retrospective data suggest that some small HER2-positive cancers might have a worse clinical outcome than others. This notion raises the key clinical question of whether patients with small HER2-positive cancers should be offered adjuvant trastuzumab and chemotherapy. The pivotal adjuvant trastuzumab trials did not include patients with tumours smaller than 1 cm, but a subset analysis of one trial showed that patients with tumours 1-2 cm in size derived at least as much clinical benefit from 1 year of adjuvant trastuzumab as did the overall cohort. Clinicians face the dilemma of whether the potential reduction in risk of recurrence in this patient group warrants the toxic effects and risks of adjuvant chemotherapy and trastuzumab. In this review, we discuss the evidence for prognosis of small HER2-positive cancers, and for possible benefit from adjuvant trastuzumab. We suggest potential treatment strategies and clinical trial designs to address this important issue. On the basis of present evidence, we recommend that the benefits and risks of adjuvant trastuzumab should be discussed with patients with small, HER2-positive breast cancer.

Triple negativity and young age as prognostic factors in lymph node-negative invasive ductal carcinoma of 1 cm or less

BACKGROUND

Whether a systemic adjuvant treatment is needed is an area of controversy in patients with node-negative early breast cancer with tumor size of ≤1 cm, including T1mic.

METHODS

We performed a retrospective analysis of clinical and pathology data of all consecutive patients with node-negative T1mic, T1a, and T1b invasive ductal carcinoma who received surgery between Jan 2000 and Dec 2006. The recurrence free survival (RFS) and risk factors for recurrence were identified.

RESULTS

Out of 3889 patients diagnosed with breast cancer, 375 patients were enrolled (T1mic:120, T1a:93, T1b:162). Median age at diagnosis was 49. After a median follow up of 60.8 months, 12 patients developed recurrences (T1mic:4 (3.3%), T1a:2 (2.2%), T1b:6 (3.7%)), with a five-year cumulative RFS rate of 97.2%. Distant recurrence was identified in three patients. Age younger than 35 years (HR 4.91; 95% CI 1.014-23.763, p = 0.048) and triple negative disease (HR 4.93; 95% CI 1.312-18.519, p = 0.018) were significantly associated with a higher rate of recurrence. HER2 overexpression, Ki-67, and p53 status did not affect RFS.

CONCLUSIONS

Prognosis of node-negative breast cancer with T1mic, T1a and T1b is excellent, but patients under 35 years of age or with triple negative disease have a relatively high risk of recurrence.

Small HER2-positive, node-negative breast cancer: who should receive systemic adjuvant treatment?

Adjuvant treatment of early-stage breast cancer with combined trastuzumab and chemotherapy has become standard in patients with HER2-positive tumors and a diameter of >1 cm or positive lymph nodes. Currently, there are no data directly supporting the use of adjuvant treatment, including trastuzumab, in patients with HER2-positive tumors, a diameter of ≤1 cm and no nodal involvement (pT1a,bpN0M0). However, 6%-10% of these small tumors are HER2 positive, and there is good evidence for an inferior clinical outcome in these patients, with recurrence rates of up to 30% after 5-10 years. Assumed that the relative risk reduction is similar to larger tumors, the absolute benefit should be large enough to consider adjuvant treatment. This review addresses current data regarding the prognosis of small HER2-positive tumors and discusses potential factors to individualize adjuvant treatment in patients with small HER2-positive tumors.

A risk stratification by hormonal receptors (ER, PgR) and HER-2 status in small (< or = 1 cm) invasive breast cancer: who might be possible candidates for adjuvant treatment?

As the use of screening mammography expands, the proportion of invasive breast cancer > or = 1 cm is increasing. The aims of this study were: (1) to identify risk factors for systemic metastases in patients with > or = 1 cm invasive breast cancer and (2) to investigate the patient groups at the greatest risk for metastases with such small tumors. Data were collected retrospectively from the breast cancer registry of our institution for patients with invasive breast cancer from October 1994 to December 2004. Of 4,036 patients who received curative breast cancer surgery, we identified 427 patients who had T1a or T1b breast cancer excluding 39 patients who received neoadjuvant chemotherapy. Ipsilateral axillary lymph node involvement was found in 13% (57/427) of patients at the time of surgery. A multivariate analysis was conducted in 370 (T1aN0, T1bN0) patients without lymph node involvement. In a Cox-regression model, HER-2 positive and triple negative (TN) groups were identified as independent risk factors to predict distant relapse-free survival (DRFS) [Hazard ratio (HR) 8.8, P = 0.003 for HER-2 positive group; HR 5.1, P = 0.026 for TN group] in T1bN0 tumors. Statistical significance was not maintained when the analysis was limited to T1aN0 tumors. Even though T1aN0 and T1bN0 tumors have a relatively low risk of systemic failure, antiHER-2-directed therapy for HER-2 group and new innovative adjuvant systemic treatment for TNBC patients with T1bN0 tumors should be considered. Prospective adjuvant trials are warranted in these subgroups of patients.

Should adjuvant trastuzumab be offered in very early-stage (pT1a/bN0M0) HER2-neu-positive breast cancer? A current debate

There are many controversies regarding the treatment of very early-stage (pT1a/bN0M0) breast cancer (BC), generally considered to have a very good prognosis. The debate is the benefit of an adjuvant treatment of HER2-neu (namely HER-2)-positive subcentimetric carcinoma with trastuzumab. Current guidelines do not suggest, with the highest level of evidence, whether trastuzumab should be administered after adjuvant chemotherapy in the treatment of high-risk pT1a/bN0M0 breast cancer. The major phase III trials that confirmed the benefit of adjuvant immunotherapy did not include small (<1 cm diameter) node-negative breast cancer. Several retrospective case series of HER-2-positive pT1a/bN0M0 carcinoma seem to demonstrate that they have a higher risk of relapse compared to the HER-2-negative counterpart. HER-2 also seems to confer an independent risk of recurrence and/or death in a multivariate analysis within large node-negative breast cancer populations. In particular, the best way to select higher-risk tumours that may achieve the best results from a trastuzumab-based therapy appears to be the in situ hybridization, which should follow the new recommended algorithm of the ASCO/CAP guidelines in case of doubtful results. According to the evidence that the survival of HER-2-positive BC can be improved with the introduction of trastuzumab respect to the HER-2-negative counterpart, there is today less uncertainty about the curative role of anti-HER-2 therapy in very early disease.

Breast cancer subtypes and the risk of local and regional relapse

PURPOSE

The risk of local and regional relapse associated with each breast cancer molecular subtype was determined in a large cohort of patients with breast cancer. Subtype assignment was accomplished using a validated six-marker immunohistochemical panel applied to tissue microarrays.

PATIENTS AND METHODS

Semiquantitative analysis of estrogen receptor (ER), progesterone receptor (PR), Ki-67, human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR), and cytokeratin (CK) 5/6 was performed on tissue microarrays constructed from 2,985 patients with early invasive breast cancer. Patients were classified into the following categories: luminal A, luminal B, luminal-HER2, HER2 enriched, basal-like, or triple-negative phenotype-nonbasal. Multivariable Cox analysis was used to determine the risk of local or regional relapse associated the intrinsic subtypes, adjusting for standard clinicopathologic factors.

RESULTS

The intrinsic molecular subtype was successfully determined in 2,985 tumors. The median follow-up time was 12 years, and there have been a total of 325 local recurrences and 227 regional lymph node recurrences. Luminal A tumors (ER or PR positive, HER2 negative, Ki-67 < 1%) had the best prognosis and the lowest rate of local or regional relapse. For patients undergoing breast conservation, HER2-enriched and basal subtypes demonstrated an increased risk of regional recurrence, and this was statistically significant on multivariable analysis. After mastectomy, luminal B, luminal-HER2, HER2-enriched, and basal subtypes were all associated with an increased risk of local and regional relapse on multivariable analysis.

CONCLUSION

Luminal A tumors are associated with a low risk of local or regional recurrence. Molecular subtyping of breast tumors using a six-marker immunohistochemical panel can identify patients at increased risk of local and regional recurrence.

Stage I breast cancer in a regional oncology practice in Israel 2002-2006: clinicopathologic features, risk estimation and planned therapy of 328 consecutive patients

We present the clinicopathologic features and treatment plans of 328 consecutive stage I (T1N0M0) breast cancer patients seen at a regional medical center in Israel. Predicted 10-year mortality risk was calculated using the Adjuvant! Online website. The 21-gene recurrence score (RS) (OncotypeDx) was obtained on a minority of patients. Eighty-nine per cent of patients had estrogen receptor (ER) and/or progesterone receptor (PgR) positive tumors. In 43.3% of patients history of an invasive malignancy was reported in a first degree relative and in 15.5% specifically breast and/or ovarian cancer was reported. Chemotherapy was added to endocrine therapy in 59 ER/PgR positive patients, decreasing predicted 10-year mortality risk by a median of 1.8%. Individualized risk estimation by genetic analysis may further decrease the use of chemotherapy in stage I patients. Breast cancer screening may provide an opportunity to identify cancer prone families.