Tag: Breast Cancer

SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. Approximately 266,120 new cases of invasive breast cancer will be diagnosed in 2018 and about 40,920 women will die of the disease. The HER or erbB family of receptors consist of HER1, HER2, HER3 and HER4. Approximately 15-20% of invasive breast cancers overexpress HER2/neu oncogene, which is a negative predictor of outcomes without systemic therapy. HERCEPTIN® (Trastuzumab) is a humanized monoclonal antibody targeting HER2, and adjuvant and neoadjuvant chemotherapy given along with HERCEPTIN® reduces the risk of disease recurrence and death, among patients with HER2-positive, early stage as well as advanced metastatic breast cancer. Since the approval of HERCEPTIN®, several other HER2-targeted therapies have become available. Accurate determination of HER2 status of the tumor is therefore essential for patients with invasive breast cancer, to ensure that those most likely to benefit are offered a HER2-targeted therapy and those who are unlikely to benefit can avoid toxicities as well as financial burden associated with those drugs.

Laboratory testing for HER2 status in patients with breast cancer in the US is performed according to guidelines developed by an Expert panel of members of the American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP). The ASCO/CAP guidelines were first published in 2007 and were updated in 2013. The Expert panel in 2018 developed and issued a focused update of the clinical practice guideline on HER2 testing in breast cancer. This new information made available since the previous update in 2013 addresses uncommon clinical scenarios and improves clarity, particularly for infrequent HER2 test results that are of uncertain biologic or clinical significance. There are currently two approved methods for determining HER2 status in breast cancer: ImmunoHistoChemistry (IHC) and In Situ Hybridization (ISH). This new guideline enables the Health Care Provider, how to best evaluate some of the less common patterns in HER2 results emerging from ISH.

Guideline Questions

1) What is the most appropriate definition for ImmunoHistoChemistry (IHC) 2+ (IHC equivocal)?

2) Must Human Epidermal growth factor Receptor 2 (HER2) testing be repeated on a surgical specimen if the initially tested core biopsy is negative?

3) What is the optimal algorithm for less common patterns observed when performing dual-probe In Situ Hybridization (ISH) HER2 testing in breast cancer?

Updated Recommendations

1) Immunohistochemistry (IHC) 2+ is defined as invasive breast cancer with weak to moderate complete membrane staining observed in more than 10% of tumor cells.

2) If the initial HER2 test result in a core needle biopsy specimen of a primary breast cancer is negative, a new HER2 test may (not “must”) be ordered on the excision specimen based on some criteria (such as tumor grade 3).

3)The HER2 testing algorithm now includes more rigorous interpretation criteria of the less common patterns that can be seen in about 5% of all cases when HER2 status in breast cancer is evaluated using a dual-probe ISH assay. These scenarios are described as ISH group 2 (HER2/Chromosome Enumeration Probe 17 [CEP17] ratio of 2.0 or more; average HER2 copy number less than 4.0 signals per cell), ISH group 3 (HER2/CEP17 ratio less than 2.0; average HER2 copy number 6.0 or more signals per cell), and ISH group 4 (HER2/CEP17 ratio less than 2.0; average HER2 copy number 4.0 or more and less than 6.0 signals per cell). These cases, described as ISH groups 2-4, should now be assessed using a diagnostic approach that includes a concomitant review of the IHC (ImmunoHistoChemistry) test, which will help the pathologist make a final determination of the tumor specimen as HER2 positive or negative.

4)The Expert Panel also preferentially recommends the use of dual-probe instead of single-probe ISH assays, but it recognizes that several single-probe ISH assays have regulatory approval in many parts of the world. 

Human Epidermal Growth Factor Receptor 2 Testing in Breast Cancer: American Society of Clinical Oncology/College of American Pathologists Clinical Practice Guideline Focused Update. Wolff AC, Hammond EH, Allison KH, et al. J Clin Oncol 2018; 36:2105-2122.

SUMMARY: Breast implants are among the most commonly used medical devices and the number of women with breast implants diagnosed with Anaplastic Large Cell Lymphoma in the breast (breast-ALCL) have increased over the past 10 years. The FDA in 2011, identified a possible association between breast implants and the development of Anaplastic Large Cell Lymphoma (ALCL), and there has been growing body of medical literature describing the natural history and long term outcomes of the disease. In 2016, the World Health Organization designated Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) as a T-Cell Lymphoma that can develop following breast implants.

The incidence of ALCL is higher with macrotextured implants than smooth implants. It has been postulated that textured implants have an increased surface area and a local inflammatory response, elicited by silicone-derived products or specific bacterial species adherent to the prosthesis surface (Biofilm) may play a role, potentiating capsular contracture and increasing T-cell response and possible conversion to BIA-ALCL. It remains unclear however, whether certain women including those with proven BRCA mutations have a genetically determined increased risk to develop lymphoma when exposed to breast implants via a genetically determined altered or exaggerated local immunological response. There are presently no evidence-based guidelines on how this condition should be detected, treated or followed up. It is however, suggested that any seroma more than 6-12 months after breast implantation, in the absence of infection, should be evaluated with ultrasonography and mammography, to identify a mass or lymph nodes that are suspicious for lymphoma. The seroma should be aspirated and the fluid analyzed for cytology, cultures, flow cytometry and cell block. If cytology is negative, patients should be closely monitored for recurrence of seroma. Biopsy should be performed if a mass is present, and if ALCL is confirmed, patients will respond to capsulectomy and removal of the implant, as ALCL confined within the capsule often have an indolent course and good prognosis. In contrast, patients who present with a distinct mass may have a more aggressive disease course and poor prognosis, and require chemotherapy and/or radiation therapy. Postoperatively evaluation if BIA-ALCL is confirmed, should include a PET-CT scan and bone marrow biopsy to rule out systemic disease. It is recommended that patients receive clinical follow up at least every 6 months for 5 years along with breast ultrasonography for 2 years, and those who undergo reinsertion of the implant should be followed up beyond 5 years.

In this publication, a case-control study was conducted, comparing the prevalence of breast implants between women with primary breast-ALCL and women with primary breast lymphomas other than ALCL, using a comprehensive Dutch pathology database. The purpose of this study was to determine the relative and absolute risks of breast ALCL in women with breast implants. The authors identified all patients diagnosed with primary Non Hodgkin Lymphoma in the breast between 1990 and 2016 and retrieved clinical data, including breast implant status, from the treating physicians, through the population-based nationwide Dutch pathology registry. They then calculated the risk of breast-ALCL in women both with and without breast implants.

The estimated prevalence of breast implants in women aged 20-70 years was 3.3%. It was noted that among 43 patients with breast-ALCL (median age 59 years), 32 had ipsilateral breast implants, compared with 1 among 146 women with other primary breast lymphomas. The median time to development of Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) was 13 years after an implant was placed. Most cases of BIA-ALCL (75%) in this Dutch study were associated with macrotextured implants and the Complete Remission rate was 90% after treatment and only 6% of the 32 affected women died of disseminated disease. In this study, the number of women with implants needed to cause 1 breast-ALCL case before age 75 years was 6920. Affected patients had implants for cosmetic reasons alone, for reconstruction in transgender surgery, after breast cancer surgery, and after prophylactic mastectomy for high breast cancer risk.

It was concluded that breast implants are associated with increased risk of breast-ALCL, but the absolute risk remains small. With an increasing number of breast implant insertions, the need for increased awareness among the public, medical professionals, and regulatory bodies is imperative and it is essential to promote alternative cosmetic procedures, and recognize this rare clinical entity. Breast Implants and the Risk of Anaplastic Large-Cell Lymphoma in the Breast. de Boer M, van Leeuwen FE, Hauptmann M, et al. JAMA Oncol. 2018;4:335-341.

SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. Approximately 266,120 new cases of invasive breast cancer will be diagnosed in 2018 and about 40,920 women will die of the disease. The HER or erbB family of receptors consist of HER1 (EGFR), HER2, HER3 and HER4. Approximately 15-20% of invasive breast cancers overexpress HER2/neu oncogene, which is a negative predictor of outcomes without systemic therapy. Approximately 50% of HER2-positive breast cancers are Hormone Receptor positive.

Patients with HER2-positive metastatic breast cancer are often treated with anti-HER2 targeted therapy along with chemotherapy, irrespective of hormone receptor status, and this has resulted in significantly improved treatment outcomes. HER2-targeted therapies include HERCEPTIN® (Trastuzumab), TYKERB® (Lapatinib), PERJETA® (Pertuzumab) and KADCYLA® (ado-Trastuzumab emtansine).

Dual HER2 blockade with HERCEPTIN® and PERJETA®, given along with chemotherapy (with or without endocrine therapy), as first line treatment, in HER2 positive metastatic breast cancer patients, was shown to significantly improve Progression Free Survival (PFS) as well as Overall Survival. The superior benefit with dual HER2 blockade has been attributed to differing mechanisms of action and synergistic interaction between HER2 targeted therapies. Not all HER2-positive, Hormone Receptor positive metastatic breast cancer patients, are candidates for chemotherapy. These patients however may benefit from anti-HER2 targeted therapy given along with endocrine therapy.

Preclinical evidence suggested that endocrine resistance may be related to cross talk between HER2- and Hormone Receptor-signaling pathways. HER2 inhibition may in turn enable the Estrogen Receptor (ER) to become the primary driver of cell proliferation, resulting in relative resistance to anti-HER2 therapy. Therefore, targeting both HER2 and ER simultaneously may be essential to derive optimal benefit among patients with HER2-positive Hormone Receptor positive metastatic breast cancer. Previously published studies demonstrated improved median PFS when single HER2 blockade combined with endocrine therapy was compared with endocrine therapy alone, among treatment naïve patients with HER2-positive and Hormone Receptor positive metastatic breast cancer.

Based on the improved outcomes with dual anti-HER2 blockade compared with single HER2 blockade in both neoadjuvant as well as metastatic settings, this present study was designed to evaluate the superiority of dual HER2 blockade with TYKERB® and HERCEPTIN® given along with an Aromatase Inhibitor (AI), over single HER2 blockade with HERCEPTIN® given along with an AI, in patients with HER2-positive, Hormone Receptor positive metastatic breast cancer, who experienced disease progression after prior neo(adjuvant)/first-line HERCEPTIN® based chemotherapy. This study also included a third treatment arm of TYKERB® plus an AI, which was compared with the other two treatment groups.

The ALTERNATIVE study is an open-label, phase III trial, in which 355 patients were randomly assigned in a 1:1:1 ratio to receive either TYKERB® along with HERCEPTIN® plus an AI (N=120), HERCEPTIN® plus an AI (N=117) or TYKERB® plus an AI. TYKERB® was administered at 1000 mg orally daily in the dual HER2 blockade group and at 1500 mg orally daily in the TYKERB® plus AI group. Patients receiving TYKERB® were urged to initiate treatment with Loperamide at the onset of diarrhea. HERCEPTIN® was administered IV at a loading dose of 8 mg/kg, followed by the maintenance dose of 6 mg/kg IV every 3 weeks. Physician’s choice of AIs included either Letrozole 2.5 mg, Anastrozole 1 mg or Exemestane 25 mg, orally daily. Enrolled patients were postmenopausal women, with histologically or cytologically confirmed ER-positive and/or Progesterone Receptor-positive, HER2-positive metastatic breast Cancer, as determined in a local laboratory. Prior treatment with endocrine therapy and disease progression during or after a prior HERCEPTIN® based chemotherapy regimen in the neo(adjuvant) setting and/or in the first-line metastatic setting, was a requirement for enrollment in this study. Only one prior regimen in the metastatic setting was allowed. Patients for whom chemotherapy was felt appropriate per treating physician’s judgement, were excluded from the study. Two thirds of the patients had received HERCEPTIN® based regimens in adjuvant setting and approximately one third in metastatic setting. The Primary end point was Progression Free Survival (PFS) with dual HER2 blockade plus AI compared with HERCEPTIN® plus AI. Secondary end points included PFS comparison of other treatment groups, Overall Survival, Overall Response Rate (ORR), Clinical Benefit Rate and Safety.

The study met its Primary end point and the median PFS utilizing dual HER2 blockade with a combination of TYKERB® along with HERCEPTIN® plus an AI was 11 months, compared with 5.7 months for HERCEPTIN® plus an AI (HR=0.62, P=0.0064). This represented a 38% reduction in the risk of disease progression. The PFS benefit was consistently observed in various predefined subgroups of patients. Further, the ORR and Clinical Benefit Rate were superior in the TYKERB® along with HERCEPTIN® plus AI group compared to HERCEPTIN® plus AI group ((31.7% versus 13.7% and 41% versus 31%, respectively). Although survival data were immature, there was also a trend favoring treatment with dual HER2 (median 46 months versus 40 months). When other treatment groups were compared, the median PFS with TYKERB® plus an AI was 8.3 months compared to 5.7 months with HERCEPTIN® plus an AI (HR=0.71, P=0.036), suggesting that among HER2-positive, Hormone Receptor positive metastatic breast cancer patients, who had progressed after prior treatment with HERCEPTIN®, anti-HER2 treatment with TYKERB® along with an AI may be a reasonable alternative, although this hypothesis will need to be confirmed. Common adverse events included higher incidence of diarrhea and rash in the groups treated with TYKERB® and serious adverse events were similar across the three treatment groups. Treatment discontinuation due to adverse events was lower in the dual HER2 blockade group.

The authors concluded that dual HER2 blockade with a combination of TYKERB®, HERCEPTIN® and an Aromatase Inhibitor (AI) resulted in improved PFS compared with HERCEPTIN® plus an AI, among HER2-positive and Hormone Receptor positive metastatic breast cancer patients, who had prior HERCEPTIN® based chemotherapy and endocrine therapy in the neo(adjuvant) and/or first line metastatic setting. This dual HER2 blockade combination offers an effective and safe chemotherapy-sparing alternative treatment regimen for this patient population. Phase III, Randomized Study of Dual Human Epidermal Growth Factor Receptor 2 (HER2) Blockade With Lapatinib Plus Trastuzumab in Combination With an Aromatase Inhibitor in Postmenopausal Women With HER2-Positive, Hormone Receptor–Positive Metastatic Breast Cancer: ALTERNATIVE. Johnston SR, Hegg R, Im S, et al. J Clin Oncol 2017;36:741-748

SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. Approximately 266,120 new cases of invasive breast cancer will be diagnosed in 2018 and about 40,920 women will die of the disease. When it comes to adjuvant radiation therapy in breast cancer, the standard of care has been Whole Breast Irradiation (WBI), administered in Conventional Fractions (CF-WBI) of 180 to 200 cGy daily, to approximately 4500 to 5000 cGy, with or without a tumor bed boost. More recently, with clinical trials supporting the safety and effectiveness of HypoFractionated Whole Breast Irradiation (HF-WBI), the American Society for Radiation Oncology (ASTRO) task force, has issued a new clinical guideline for the use of whole-breast radiation therapy for breast cancer, which replaces the existing ASTRO Whole Breast Irradiation guideline published in 2011. With HypoFractionated Whole Breast Irradiation, patients receive larger doses of radiation over a shorter period of time, typically completing treatment in 3-4 weeks, compared with 5-7 weeks for CF-WBI.

The guideline recommendations were based on a systematic literature review, between January 2009 and May 2016, and created using ASTRO-approved tools, for grading evidence quality and recommendation strength. The ASTRO convened a task force to address 5 key questions focused on dose-fractionation for WBI, indications and dose fractionation for tumor bed boost, and treatment planning techniques for WBI and tumor bed boost. The recommendations are summarized below.

Whole-Breast Irradiation (without irradiation of regional lymph nodes) – Delivery and Dosing

1) Treatment decisions, including radiation techniques (Hypofractionated versus Conventional Fractions) should be a shared decision between patient and physician and should be individualized to each patient.

2) For women with invasive breast cancer receiving WBI with or without inclusion of the low axilla, the preferred dose-fractionation scheme is HF-WBI to a dose of 4000 cGy in 15 fractions or 4250 cGy in 16 fractions.

3) The decision to offer HF-WBI should be independent of age, tumor grade, hormone receptor status, HER2 receptor status, surgical margin status, breast size, breast cancer laterality, chemotherapy received prior to radiation and trastuzumab or endocrine therapy received prior to or during radiation.

4) HF-WBI may be used as an alternative to CF-WBI in patients with DCIS.

5) CF-WBI may be preferred over HFWBI when treating primary breast cancers with rare histologies that are most commonly treated with CF when arising in other parts of the body.

6) In patients with breast augmentation, either HF-WBI or CF-WBI may be used.

Tumor Bed Boost

1) A tumor bed boost is recommended for patients with invasive breast cancer 50 years or younger with any grade tumor, age 51-70 years with high grade tumor, or a positive margin. Omitting a tumor bed boost is suggested in patients with invasive breast cancer who are older than 70 years with hormone receptor-positive tumors of low or intermediate grade, resected with widely negative (2 or more mm) margins.

2) A tumor bed boost may be used for patients with DCIS, 50 years and younger, high grade tumors, or close (less than 2 mm) or positive margins following resection. A tumor bed boost may be omitted for patients with DCIS who are older than 50 years, screen detected tumor, total size 2.5 cm or less, low to intermediate nuclear grade, and have widely negative surgical margins (3 mm or more).

3) The decision to use a tumor bed boost should be based on the clinical indications for a boost and should be independent of whether the patient received Conventional or Hypofractionated WBI.

Preferred Techniques for WBI Treatment Planning

1) Three-dimensional conformal radiotherapy planning with a field-in-field technique is recommended to achieve radiation dose homogeneity and full coverage of the tumor bed.

2) Techniques that incorporate deep inspiration breath hold, prone positioning, and/or heart blocks are recommended to minimize heart dose. Treatment techniques should also minimize dose to the contralateral breast, lung, and other normal tissues.

3) Treatment plans should be individualized after consideration of many factors, including tumor characteristics, patient anatomy and comorbidities.

Radiation therapy for the whole breast: Executive summary of an American Society for Radiation Oncology (ASTRO) evidence-based guideline. Smith BD, Bellon JR, Blitzblau R, et al. DOI: https://doi.org/10.1016/j.prro.2018.01.012