Incidence, modality and timing of staging
894/896 (99.8 %) of the patients received a routine staging for distant metastasis. In 618 (69 %) detailed information about the modality of staging was known: 340 Patients had the “classical approach” of a whole-body-scintigraphy, a chest-X-ray and a liver-ultrasound, but in 33 cases use of an additional modality like CT, PET-CT or MRI to exclude metastases was documented. On the other hand 278 cases got a non-conventional staging by CT scan as a substitute for X-ray or ultrasound, but still in 3 cases an additional CT, PET-CT or MRI was necessary to exclude metastases.
In 276 cases the staging result of bone, lung and liver is known—but no report was available to verify the staging modality used. In 2 patients only a staging was omitted, so they were assigned to MX-Status.
In 236 cases timing of staging with respect to the start of oncological treatment could be evaluated: 198 patients (84 %) had a complete staging preoperatively, n = 38 postoperatively (16 %).
Results of staging (M0, M1, MX)
In 6 of 894 patients with radiological staging metastatic spread to the skeletal system (and lung in one case) at point of primary breast cancer diagnosis has been suggested. In three of these evidence for metastasis in imaging was highly conclusive, so these patients were assigned to palliative treatment without histological confirmation. One of them, however, was diagnosed with a stage cT4-tumor, thus in fact she did not fulfill criteria for participation in German Mammography Screening, which aims at woman without clinical signs of breast cancer.
In a 4th case the patient reported a traumatic event in medical history as a differential diagnosis for bone metastasis. This patient was assigned to adjuvant treatment. Follow-ups did not confirm distant metastasis and this patient remained in adjuvant treatment concept.
A 5th patient had the initial staging suspicion of bone-metastasis but treatment choice remained adjuvant. Follow-ups by whole-body-scintigraphy and MR-scan finally excluded bone metastases.
In a 6th patient the suspicion of distant bone metastasis was excluded via biopsy. The histological result confirmed the patients hyperparathyreoidism as the cause for multiple osteolytic lesions in imaging. The patient was finally staged M0, treatment followed adjuvant criteria.
Implications for oncological treatment
The oncological concept has been modified in 3/894 patients due to the findings in staging for distant disease. Characteristics of the patients and treatment chosen are reported.
Patient 1
The 68 year old patient had bowel-cancer in medical history 30 years ago. She was first time participating in German Breast Cancer Screening Programme. She presented with a screening-detected hormone-receptor-positive ductal invasive breast cancer, G2, Ki67 = 20 %. Mastectomy was done at the patients request with sentinel-node axillary staging. The histological result was pT2 pN0 (sn-) L0 R0. The postoperative staging by whole-body-scintigraphy showed suspicion of bone metastasis, which was confirmed by MR- and CT-scan. Due to imaging—but without histological confirmation—the patient was assigned to palliative endocrine therapy and bone-modifying RANKL-antibody (Denosumab) and additional radiotherapy of pelvic bone metastasis.
Patient 2
In the 59 year old patient a hormone-receptor-positive ductal invasive breast cancer was diagnosed. Breast conserving therapy and axillary staging resulted in pT2 pN1a G3 ER90 % PR90 % Her2neg breast cancer. Timing of staging was not known but resulted in suspicion of bone metastasis to the lumbar spine and was confirmed by MR-scan. The patient has been treated deviating from guidelines by 4 cycles of epirubicin/cyclophosphamide chemotherapy followed by aromatase inhibitors. Bisphosphonates and local radiotherapy of the lumbar spine were added.
Patient 3
The 58 year old patient was first time participating in Screening, but presented with an inflammatory cT4 breast cancer and clinical signs of axillary lymph node metastasis. Histology confirmed a ductal invasive type of breast cancer, hormone-receptor-positive, Her2-negative, no Ki67-value was documented. Staging showed distant metastasis in bone and lung which lead to palliative chemotherapy with Paclitaxel and anti-VEGF-antibody Bevacizumab.
Patients 4–6, whose metastasis were not confirmed, were between 60 and 65 years old. All of them showed invasive ductal breast cancer, pT1c, pN0 (sn-), G2, R0. Metastasis could be precluded by follow up control in 2 patients, and by biopsy in 1 patient, which revealed a hyperparathyroidism. All were treated in the adjuvant protocol according to the current guidelines.