Breast Cancer (Mammary Carcinoma): Test and Diagnosis

For clarification of a suspicious palpatory finding, priority is given to methods of medical device diagnostics, mammography (X-ray examination of the breast), sonography (ultrasound), magnetic resonance imaging (MRI) if necessary, and for histological (fine tissue) clarification, punch biopsy (tissue sample). Note: Every palpatory and/or sonographic suspicious finding must be clarified by histological examination (punch biopsy). 1st order laboratory parameters – obligatory laboratory tests (primarily for diagnosis and treatment planning).

• Blood/serum:
  • Inflammatory laboratory: CRP (C-reactive protein), leukocytes, ESR (erythrocyte sedimentation rate) in case of redness, swelling, pressured dolence.
• Tissue (in the context of diagnostics by punch or less frequently vacuum biopsy, in individual cases, for example, axillary lymph node puncture by fine needle aspiration, or on the surgical specimen and in the context of sentinel node biopsy):
  • Histology: tumor type, size, marginal situation (removed in healthy tissue?, safety distance to healthy tissue, vascular invasion?).
  • Lymph node status
  • Grading (assessment of the degree of differentiation of tumor tissue).
  • Hormone receptors:
    • Estrogen Receptor (ER)
    • Progesterone receptor (PgR)
  • HER2 status (synonyms: Her2 protein; cerbB 2, Her 2/neu; HER-2; human epidermal growth factor receptor; human epidermal growth factor receptor-2/neuroblastoma). In about 20% of all invasive breast carcinomas, the receptor is highly overexpressed. Thus, its effect is multiplied, which translates into a poor survival prognosis, or a comparatively worse disease course.
  • KI-67 (KI67; synonym: MIB1, proliferation marker for objectification and validation of grading, allows conclusions about growth behavior) Indication: in women with ER-/PR-positive and HER2-negative invasive breast carcinoma [Ki-67 positivity ≥ 25% → increased risk]Note: In women with invasive HER2-negative breast carcinoma and histologically confirmed positive estrogen receptor (ER)/progesterone receptor (PR), the addition of Ki 67 to conventional prognostic factors improves prognostic assessment for deciding whether adjuvant chemotherapy is indicated.
  • Tumor-infiltrating lymphocytes (TIL) in the stroma: Determination of the amount of TIL in the stroma (sTIL) at the time of diagnosis – to predict the odds of (disease-free) survival in women with triple-negative breast carcinoma (tumor type lacking both estrogen and progesterone and HER2/neu receptors) at an early stage [sTIL correlated directly with age and inversely with tumor burden; however, higher sTIL levels are also associated with higher grading; each 10% increase in stil fraction reduced the risk of
    • Invasive disease or death by 14%.
    • For distant metastases or death by 17%.
    • Risk of death by 17%]
  • UPA/PAI-1 test (urokinase-type plasminogen activator) to assess prognosis in node-negative breast carcinoma. The test provides information about recurrence risk (risk of tumor recurrence) and helps assess the benefit of chemotherapy after surgery. A high concentration is associated with a poor prognosis. Notice: Current guidelines state that the uPA/PAI-1 invasion factors should no longer be used to decide for or against adjuvant therapy in estrogen receptor (ER)-/progesterone receptor (PR)-positive and HER2-negative, node-negative breast carcinoma.
  • (Multiple testing methods (genomic testing methods, gene expression testing, gene expression profile testing, gene signature testing). They are currently still 2nd order laboratory parameters see there).

Laboratory parameters 1st order – obligatory laboratory tests (if genetic burden is suspected).

• BRCA gene status (BRCA1, BRCA2, BRCA3/RAD51C gene):
  • Blood test: DNA from peripheral lymphocytes (if genetic burden is suspected. Performed in special centers as part of genetic counseling).
    • In women with a BRCA mutation, the risk – in the course of life – of developing breast cancer is circa 60 to 80 percent, and in about 60% of cases the contralateral (“on the opposite side”) mamma is also affected.
    • The risk of developing ovarian cancer (ovarian cancer) is circa 40 to 60 percent for BRCA1 mutation carriers and circa 10 to 30 percent for BRCA2 mutation carriers.Carriers of the BRCA3 mutation (RAD51C and RAD51D) also have a high risk of approximately 20 to 40 percent for breast cancer. The risk of ovarian cancer could possibly even be higher than the risk of developing breast cancer.

Criteria for further genetic testing

2nd order laboratory parameters (for diagnosis, treatment planning, follow-up/therapy monitoring).

• Blood/serum:
  • Tumor markers: CA 15-3 (therapeutic and follow-up control of metastatic breast carcinoma; often indicates recurrence before it becomes clinically apparent), CEA.
  • Circulating metastatic stem cells: They are responsible for the development of metastases and thus the survival of the patient and differ in gene expression profile from the primary tumor (resistance to therapy)(future options).
  • Genomic testing (genetic testing) – to detect mutations in the estrogen receptor that cause resistance to hormone therapy; thus a test before starting therapy!Note: These mutations are detectable in the blood (= “liquid” biopsy), because when tumor cells die, their DNA enters the blood. In a study it could be shown that the results of the blood examination agreed in 97 % with the results of the histological examination of the biopsies. Furthermore, it was shown that a positive test result was associated with a threefold increased risk of tumor progression.
  • Tumor infiltrating lymphocytes (TIL): factor that has high prognostic value in some aggressive forms of breast cancer to predict the chances of cure and the benefit of chemotherapy [TIL ↑ = chemotherapy particularly effective].
• Tissue:
  • Multigene test methods (genomic test methods, gene expression tests, gene expression profile tests, gene signature test; genotyping; English multigene assays) They are currently still 2nd order laboratory parameters, but are increasingly used in routine for small breast carcinomas and intermediate risk (< 1 cm, N 0-3, HR receptor pos, HER-2 neg.) to differentiate which patients can forgo chemotherapy.The Gynecologic Oncology Study Group (AGO) recommends these procedures when a decision regarding chemotherapy cannot be made based on clinicopathologic factors.Data from the planB trial confirm that patients with HER2-negative early breast cancer can safely forgo chemotherapy when a gene expression test indicates low tumor aggressiveness:
    • EndoPredict test-8-gene signature (material: biopsy; one section (tumor proportion 30%) of a tissue block):
      • EP score: explanation and weighting of the eight disease-relevant genes.
      • EPclin Score: calculation of EPclin score by adding tumor size and nodal status; statement about risk of relapse in the next ten years; assignment of high- or low-risk group (chemotherapy/no chemotherapy).
      • Chemobenefit: calculation of “chemobenefit” according to EBCTCG (Lancet 2012): chemotherapy can reduce the risk of metastasis by about one-third.
    • MammaPrint test – 70-gene signature (material: biopsy/fresh or formalin-fixed tumor tissue).
      • Result: low risk of metastasis (good prognosis) or high risk of metastasis (poor prognosis).
      • Indications (ASCO lessons from MINDACT):
        • Patients with hormone receptor-positive, HER2-negative, and lymph node-negative breast cancer who are at high clinical risk. Here, the test can identify patients with good prognosis who potentially have limited benefit from chemotherapy.
        • Patients with hormone receptor-positive, HER2-negative breast cancer and one to three positive lymph nodes who are at high clinical risk. Here, the test can identify patients with a good prognosis who potentially have limited benefit from chemotherapy. However, women must be clearly told that benefit from systemic therapy cannot be ruled out, especially if more than one lymph node is affected.
      • Contraindications:
        • Patients with hormone receptor-positive, HER2-negative, and lymph node-negative breast cancer who are at low clinical risk. Since their prognosis is good anyway and is not improved by chemotherapy, even if there is a high genetic risk.
        • Patients with hormone receptor-positive, HER2-negative breast cancer and one to three positive lymph nodes who are at low clinical risk (no evidence of benefit to date based on data).
        • Patients with HER2-positive breast cancer (further studies are awaited).
        • Patients with triple-negative breast cancer to decide adjuvant chemotherapy.
    • Oncotype DX test – 21-gene recurrence score (material: biopsy/tumor block (or tissue sections generated from it)). [Statutory health insurance benefit]
      • Recurrence Score (patient’s 10-year risk of recurrence) and potential individual benefit of chemotherapy as a percentage; score is reported with range 0 to 100. This range is divided into three risk categories: low (<18), intermediate (18-30), and high risk
      • TAILORx study: one of the outcomes investigated was whether women with intermediate Oncotype risk scores (11 to 25) were significantly more likely to have recurrences without additional chemotherapy than with chemotherapy. Results showed that adjuvant hormonal therapy was effective, as were hormonal therapy and chemotherapy together. After 9 years of follow-up, the rates of invasive disease-free survival were 83.3% for hormone therapy alone and 84.3% for hormone therapy and chemotherapy, and for overall survival, the rates were 93.9% and 93.8%. CONCLUSION: Adjuvant endocrine therapy and chemoendocrine therapy had similar efficacy in women with hormone receptor-positive, HER2-negative, axillary node-negative breast carcinoma who had a 21-gene recurrence score in the intermediate range, although some women aged 50 years or younger were found to benefit from chemotherapy.
    • Prosigna – PAM-50 gene signature (group of 50 genes); indication: newly diagnosed patients with node-negative or node-positive, hormone receptor-positive (HR+), and HER2-negative (HER2-) early breast cancer; results:
      • Determination of risk of recurrence (ROR).
      • Information about the biological subtype of the tumor.
    • Two other tests for additional information about the breast tumor:
      • TargetPrint – quantitative determination of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor (HER2) expression, using DNA microarray technology.
      • BluePrint – 80-gene profile; classifies breast cancer into basal type, luminal type, or ErbB2 (HER2) type. This so-called molecular subtyping of tumors is done to determine which therapy the tumor is likely to respond to.
  • Histological control examination, for example, after neoadjuvant chemotherapy or metastases (daughter tumors), because the biology of the tumor can change significantly over time, or resistance to therapeutic agents arise (examination methods see laboratory parameters 1st order).

Predictive biomarker

• Proneurotensin 1-117 (pro-NT): predictive biomarker that provides information about the change in risk of developing breast cancer with statistically significant results.With the Malmö Diet And Cancer study (MDC) in 2012, the relationship between pro-NT concentration in the blood and breast cancer risk was demonstrated. This showed that increased pro-NT concentrations are associated with an approximately 3-fold increased risk of developing breast cancer over the following 5-15 years.
• Carboanhydrase IX (a soluble zinc metal enzyme) [low enzyme level = combination of neoadjuvant chemotherapy with bevacizumab is associated with better pathological complete response than high levels].