Detection of isolated ipsilateral regional lymph node recurrences by F18-fluorodeoxyglucose positron emission tomography-CT in follow-up of postoperative breast cancer patients

Internal mammary lymph node metastasis in breast cancer patients based on anatomical imaging and functional imaging

Internal mammary lymph node (IMLN) metastasis forms part of the clinical node classification for primary breast cancer, which influences the treatment strategy. However, because of the IMLNs' complicated anatomical structures and relationships with adjacent structures, IMLN biopsy or resection is associated with a limited improvement in prognosis and a high complication rate. The positivity rate also varies broadly according to imaging modality, and there is a low rate of agreement between the imaging and pathological diagnoses, which creates imprecision in the preoperative staging. The IMLN positivity rate also varies remarkably, and there are no clear, accurate, and non-invasive modalities for diagnosing the pre-mastectomy IMLN status. Nevertheless, medical imaging modalities continue to evolve, with functional imaging and image-guided thoracoscopic biopsy of sentinel IMLNs being well established. Thus, personalized decision-making and treatment selection should be based on the modality-specific differences in the diagnosis of IMLN metastasis/recurrence and the patient's specific risk factors.

Internal mammary lymph node metastases in breast cancer: what should radiologists know?

The internal mammary lymph node (IMLN) chain is a pathway through which breast lymphatic drainage flows. The internal mammary lymphatic vessel runs around the internal mammary artery and veins with IMLN in the parasternal intercostal spaces. IMLN metastasis, which forms a part of clinical TNM staging, may negatively affect the prognosis of primary breast cancer patients. IMLN metastasis is clinically detected using ultrasound, computed tomography, magnetic resonance imaging, and ¹⁸F-deoxyglucose positron emission tomography computed tomography. The uptake of radioactive tracers in IMLN with clinically negative axillary lymph nodes is often identified using sentinel lymph node mapping (SLNM) in primary breast cancer patients. The indication for IMLN biopsy or resection that is clinically detected or visualized using SLNM is controversial. The clinically suspicious IMLN may be considered for ultrasound-guided fine-needle aspiration. First IMLN recurrence needs to be biopsied. Irradiation of the breast, chest wall, and/or regional nodal irradiation, including IMLN, following lumpectomy or postmastectomy is recommended. Although radiation therapy for IMLN recurrence may improve clinical outcomes, it is also associated with pulmonary and cardiac toxicities. This review covers the local anatomy of IMLN, lymph drainage and image findings of IMLN with a discussion.

Implementation of a Systematic Literature Search Strategy in a National Breast Cancer Guideline: The Relevance of Systemic Therapy in Lymph Node Recurrent Disease

PURPOSE

Our aim was to implement a structured literature search using PICO (patient/intervention/comparison/outcome) questions and a standardized consensus method for the German Guideline 'Detection, diagnostics, therapy and follow-up of Breast Cancer' using, as an example, the significance of systemic therapy in lymph node recurrent disease (LNRD).

METHODS

We defined specified PICO questions according to the clinical significance of a recommendation for systemic therapies in locoregional LNRD. A methodologist performed a systematic literature search including randomized controlled trials, systematic reviews and observational studies (2007-2016). In a consensus conference, the level of evidence and consensus was determined and the clinical recommendation was adopted.

RESULTS

In total 143 publications were identified according to the search strategy including 14 duplicates, which were excluded. 4 publications were included based on experts' choice. The team excluded 119 publications, leaving 14 that were then screened by a full text search. Finally, 1 publication was found to be of methodologically and clinically reliable content. The conclusion of this publication in favor of systemic therapy for LNRD received strong consent from the consensus conference.

CONCLUSIONS

The literature search strategy using PICO questions helped to achieve a fast and standardized selection of publications. The recommendation concerning systemic treatment of LNRD was first implemented in the update of the German Breast Cancer guideline.

Significance of primary lesion resection in Stage IV breast cancer

Systemic treatment with drugs is administered to prolong survival and palliate symptoms in Stage IV breast cancer patients who have distant metastases at diagnosis. Surgical procedures for the primary tumor are not actively recommended in guidelines due to lack of evidence indicating prognostic benefit. Recently, several retrospective studies have shown primary tumor resection to prolong overall survival in patients with Stage IV breast cancer. Prospective randomized trials began enrolling patients to examine this possibility and two have already reported results. However, the results of these two trials were discordant. The first trial, conducted in India, reported negative effects of primary tumor resection after primary systemic therapy. A Turkish trial then obtained a positive effect of surgery as primary treatment. Several questions regarding the effects, timing, methods and eligibility for primary surgery have yet to be answered. Robust evidence, which is anticipated from other ongoing trials examining surgery for metastatic breast cancer, is eagerly awaited.

Resection of the primary tumor in stage IV breast cancer

Stage IV breast cancer refers to breast cancer that has already metastasized to distant regions when initially diagnosed. Treatment for stage IV is intended to “prolong survival and palliate symptoms”. Resection of a primary tumor is considered to be “effective only at alleviating chest symptoms and providing local control” in spite of the advances of imaging examination and medication for breast cancer. Molecular target and endocrine drugs are very effective and useful to tailor-make a treatment strategy according to breast cancer subtypes. Positron emission tomography-computed tomography can detect and diagnose the very small metastases and recurrences which can potentially be cured even if they are distant metastases. Recently, many retrospective studies have reported the survival benefit of surgery for breast cancer patients with metastases and some clinical trials which confirm the surgical prognostic benefit for them have started to enrol patients. The goal of treatment has to be clearly identified: increase the patient’s survival time, provide local control or perform histology to determine the cancer’s properties. The best evidence is absolutely essential to treat patients who need surgery at the right time. We need to evaluate the treatment strategy, including primary resection for stage IV breast cancer particularly, and find new evidence by prospective analysis.

Role of maximum standardized uptake value in fluorodeoxyglucose positron emission tomography/computed tomography predicts malignancy grade and prognosis of operable breast cancer: a multi-institute study

The malignant biological behavior of breast cancer remains obscure on diagnostic images, although understanding the grade of such malignancy is important for selecting appropriate treatment. Therefore, malignancy grades in operable breast cancer were evaluated using positron emission tomography/computed tomography (PET/CT) in a multicenter setting. We prospectively examined the features and prognosis of 344 patients (mean age ± SD: 58.0 ± 12.5 years) with clinical stages I–III breast cancer, who underwent surgical intervention without induction therapy between January 2006 and December 2011. Maximum standardized uptake values (maxSUV) obtained from whole-body fluorodeoxyglucose-PET/CT immediately before surgery were assessed to predict the malignant aggressiveness of tumors including the recurrence-free survival of the patients. Variations in maxSUV among institutions, which are limitations of PET assessments in multicenter studies, were adjusted using a phantom study. The median follow up period was 52 months. The patients were divided into groups according to cut-off maxSUV (≤3.0 vs. >3.0) values established from receiver operating characteristic analysis of recurrence (area under the curve = 0.713). A higher maxSUV was significantly associated with a higher T-factor (p < 0.0001), N-factor (p = 0.0049), nuclear grade (p < 0.0001), negative for estrogen (p = 0.0309), and progesterone receptors (p = 0.0063), positive for human epidermal growth factor receptor 2 (p = 0.0012), lymph node metastasis (p = 0.0128), and vascular invasion (p = 0.0110). Multivariate analysis using Cox proportional hazard regression model revealed high maxSUV and negative estrogen receptor status as significantly prognostic factors (p = 0.033 and p = 0.004, respectively). This study demonstrated that maxSUV on PET/CT as well as estrogen receptor status is useful to predict malignancy grades and the prognosis of patients with breast cancer.