Postmastectomy radiation therapy for inflammatory breast cancer: is more better?

Radiation for inflammatory breast cancer: Updates

Inflammatory breast cancer (IBC) is a diagnosis based on a constellation of clinical features of edema (peau d'orange) of a third or more of the skin of the breast with a palpable border and a rapid onset of breast erythema. Incidence of IBC has increased over time, although it still makes up only 1-4% of all breast cancer diagnoses. Despite recent encouraging data on clinical outcomes, the published local-regional control rates remain consistently lower than the rates for non-IBC. In this review, we focus on radiotherapy, provide a framework for multi-disciplinary care for IBC, describe local-regional treatment techniques for IBC; highlight new directions in the management of patients with metastatic IBC and offer an introduction to future directions regarding the optimal treatment and management of IBC.

Imaging for Radiation Planning in Breast Cancer

Radiation therapy is an integral component of the treatment of breast cancer. The indications and type of radiation therapy vary depending on disease invasiveness and stage. Imaging is the cornerstone for radiation therapy planning. While conventional imaging with CT remains the primary modality for radiation treatment planning locally in the breast, molecular imaging with [¹⁸F]FDG-PET/CT identifies additional occult disease that may help alter the local radiation therapy plan or treat oligometastatic disease. The ultimate effects on long-term outcomes remain to be determined. This article reviews the role of imaging in radiation planning for breast cancer.

Discrepancy between FDG-PET/CT and contrast-enhanced CT in the staging of patients with inflammatory breast cancer: implications for treatment planning

PURPOSE

Optimizing treatment strategies for patients with inflammatory breast cancer (IBC) relies on accurate initial staging. This study compared contrast-enhanced computed tomography (ce-CT) and FDG-PET/CT for initial staging of IBC to determine the frequency of discordance between the two imaging modalities and potential impact on management.

METHODS

81 patients with IBC underwent FDG-PET/CT and ce-CT prior to starting treatment. FDG-PET/CT and ce-CT scans were independently reviewed for locoregional and distant metastases and findings recorded by anatomic site as negative, equivocal, or positive for breast cancer involvement. Each paired ce-CT and FDG-PET/CT case was classified as concordant or discordant for findings. Discordant findings were subclassified as (a) related to the presence or absence of distant metastases; (b) affecting the locoregional radiation therapy plan; or (c) due to incidental findings not related to IBC.

RESULTS

There were 47 discordant findings between ce-CT and FDG-PET/CT in 41 of 81 patients (50.6%). Thirty (63.8%) were related to the presence or absence of distant metastases; most commonly disease detection on FDG-PET/CT but not ce-CT (n = 12). FDG-PET/CT suggested alterations of the locoregional radiation therapy plan designed by CT alone in 15 patients. FDG-PET/CT correctly characterized 5 of 7 findings equivocal for metastatic IBC on ce-CT.

CONCLUSIONS

This study demonstrates differences between ce-CT and FDG-PET/CT for initial staging of IBC and how these differences potentially affect patient management. Preliminary data suggest that FDG-PET/CT may be the imaging modality of choice for initial staging of IBC. Prospective trials testing initial staging with FDG-PET/CT versus important clinical end-points in IBC are warranted.

Inflammatory Breast Cancer in Pregnancy and Lactation

Inflammatory breast cancer (IBC) represents only 1% to 5% of all breast malignancies and is an extremely aggressive subtype. At time of diagnosis, up to 85% of patients will present with regional nodal metastases and up to 30 % will have metastasis to distant organs. There is limited medical literature describing treatment guidelines for IBC during gestation. The best diagnostic tools are core needle and full-thickness skin punch biopsies to assess presence of dermal lymphatic invasion. Breast Ultrasound is preferred to mammogram, but mammography could still be done with proper fetal shielding. Ultrasound and Magnetic resonance imaging are used for staging. Pregnant patients should be managed with special attention to the health of the fetus by a multidisciplinary team. Treatment based on current guidelines consist of a sequence of systemic chemotherapy followed by mastectomy with axillary dissection (modified radical mastectomy), and even if good clinical nodal response to neoadjuvant therapy is obtained, sentinel node biopsy is not recommended. Radiation therapy is to be given once the baby has been delivered. Chemotherapy is not recommended in the first trimester, and anti-estrogen hormonal therapy, as well as targeted Her2-neu therapies are contraindicated during the length of the pregnancy. There is no evidence that early termination improves the outcome. However, given the poor prognosis of IBC, patients should be fully counseled on the risks and benefits of continuing or terminating an early pregnancy.

Inflammatory Breast Cancer: a Separate Entity

PURPOSE OF REVIEW

Inflammatory breast cancer (IBC) is an uncommon but highly aggressive subtype of breast cancer that contributes significantly to breast cancer-related mortality. In this review, we provide an overview of the clinical and molecular characteristics of IBC, and highlight some areas of need for ongoing research.

RECENT FINDINGS

The disease is characterized by florid tumor emboli that obstruct dermal lymphatics, leading to swelling and inflammation of the affected breast. Recent studies have focused on tumor cell intrinsic features, such as signaling through pathways involved in growth and stem-like behavior, as well as extrinsic features, such as the immune system, that can be leveraged to develop new potential therapies. Key efforts have led to an increase in awareness of the disease as well as new insights into IBC pathogenesis. However, there is a strong need for new therapies designed specifically for IBC, and many unanswered questions remain.

Excellent Locoregional Control in Inflammatory Breast Cancer With a Personalized Radiation Therapy Approach

PURPOSE

Inflammatory breast cancer (IBC) has been characterized by high locoregional recurrence (LRR) rates even after trimodality therapy. We recently reported excellent locoregional control among patients treated since formal dedication of an IBC-specific clinic and research program in 2006. Institutionally, a standard twice-daily (BID) dose escalation regimen for all patients with IBC was de-escalated in select cases in 2006 after review demonstrated that young age, incomplete response to neoadjuvant therapy, and positive margins identified subsets with maximal benefit from dose escalation. We report local control and toxicity rates specific to BID versus once-daily (QD) radiation therapy approaches.

METHODS AND MATERIALS

From a prospectively collected database, we identified 103 patients with nonmetastatic IBC who received trimodality therapy at our institution from 2007 to 2015. Descriptive statistics were used to describe the study cohort and compare retrospectively extracted rates of radiation therapy-associated toxicity. The actuarial rate of LRR-free survival was analyzed using the Kaplan-Meier method.

RESULTS

The median follow-up is 3.6 years. Thirty-nine patients (37.9%) received postmastectomy radiation therapy (PMRT) to the chest wall and undissected regional lymphatics in QD fractions (median dose, 50.0 Gy in 25 fractions [fx]; median boost dose, 10.0 Gy in 5 fx) and 64 patients (62.1%) received BID PMRT (median dose, 51.0 Gy in 34 fx; median boost dose, 15.0 Gy in 10 fx). Crude rates of toxicity were not different between patients treated with QD or BID PMRT. Two BID patients (3.1%) and no QD patients (0.0%) experienced LRR (P = .53). The 3- and 5-year LRR-free survival were 95.1% and 100.0% for BID and QD patients, respectively (P = .25).

CONCLUSIONS

Tailoring radiation therapy to clinical risk factors was associated with excellent locoregional control. De-escalation of PMRT from BID to QD was not clearly associated with reduced toxicity compared with BID, although retrospective data collection may limit this comparison.

Inflammatory Breast Cancer: What to Know About This Unique, Aggressive Breast Cancer

Inflammatory breast cancer (IBC) is a rare form of breast cancer that accounts for only 2% to 4% of all breast cancer cases. Despite its low incidence, IBC contributes to 7% to 10% of breast cancer caused mortality. Despite ongoing international efforts to formulate better diagnosis, treatment, and research, the survival of patients with IBC has not been significantly improved, and there are no therapeutic agents that specifically target IBC to date. The authors present a comprehensive overview that aims to assess the present and new management strategies of IBC.

International Consensus on the Clinical Management of Inflammatory Breast Cancer from the Morgan Welch Inflammatory Breast Cancer Research Program 10th Anniversary Conference

National and international experts in inflammatory breast cancer (IBC) from high-volume centers treating IBC recently convened at the 10th Anniversary Conference of the Morgan Welch Inflammatory Breast Cancer Research Program at The University of Texas MD Anderson Cancer Center in Houston Texas. A consensus on the clinical management of patients with IBC was discussed, summarized, and subsequently reviewed. All participants at the conference (patients, advocates, researchers, trainees, and clinicians) were queried using the MDRing electronic survey on key management issues. A summary of the expert consensus and participant voting is presented. Bilateral breast and nodal evaluation, breast magnetic resonance imaging, positron emission tomography/computed tomography, and medical photographs were endorsed as optimal. Neoadjuvant systemic therapy, modified radical mastectomy and level I and II ipsilateral axillary node dissection, post-mastectomy radiotherapy, adjuvant targeted therapy and hormonal therapy as indicated, and delayed reconstruction were agreed-upon fundamental premises of standard non-protocol-based treatment for IBC. Consideration for local-regional therapy in de novo stage IV IBC was endorsed to provide local control whenever feasible. Variation across centers and special circumstances were discussed.

Inflammatory breast cancer: unique biological and therapeutic considerations

Through the concerted efforts of many patients, health-care providers, legislators, and other supporters, the past decade has seen the development of the first clinics dedicated to the care of patients with inflammatory breast cancer in the USA and other countries. Together with social networking, advocacy, and education, a few specialised centres have had substantial increases in patient numbers (in some cases ten times higher), which has further expanded the community of science and advocacy and increased the understanding of the disease process. Although inflammatory breast cancer is considered rare, constituting only 2-4% of breast cancer cases, poor prognosis means that patients with the disease account for roughly 10% of breast cancer mortality annually in the USA. I propose that the unique presentation of inflammatory breast cancer might require specific, identifiable changes in the breast parenchyma that occur before the tumour-initiating event. This would make the breast tissue itself a tumour-promoting medium that should be treated as a component of the pathology in multidisciplinary treatment and should be further studied for complementary targets to inhibit the pathobiology that is specific to inflammatory breast cancer.