In this study, we introduced a special male breast cancer case with ureteral metastasis. His immunohistochemical character was rather different from the gene test. Although we adjusted his treatment regiment, this patient still had a poor result.
MBC is rather rare and the risk factors for MBC include demographic factors (black ethnicity, family history of breast cancer), genetic factors (germline genetic mutation, eg, BRCA1, BRCA2, CHEK2, PALB2), environmental factors and diseases associated with hyperestrogenism. However, there was no family history of breast cancer in this case and the genetic test of BRCA mutation was negative. At the same time, no radiation exposure or other diseases reported as risk factors such as liver disease or testicular abnormalities or obesity in this patient. As a result, the exact cause of breast cancer in this patient was unclear and risk factors of MBC should be further studied in the future.
Research data shows that MBC risk has remained at a constant level over the past 40 years. Compared with female patients, male patients have later onset and more advanced disease because of lacking of awareness of early signs of breast cancer and early detection by mammography screening. Although overall survival of MBC is usually worse, male patients actually have a survival benefit after adjustment of life expectancy, age, time of diagnosis, stage and treatment[3, 9]. In our study, the patient was at advanced stage when diagnosed, which leaded to his poor prognosis. In a word, much improvement in outcome of MBC can be achieved by improving earlier detection such as awareness and promotion of breast self-examination and development of therapy guidelines.
Breast cancer commonly metastasis to lymph nodes, lung, liver, bone or brain, and only few cases were reported metastasis to other sites such as intestine or ureter, which may be easily misdiagnosed. In this case, the patient developed a symptom of hematuresis, which was considered urinary tract infection or primary tumors at first. After pathological examination and considering his past history of breast cancer, he was diagnosed with ureteral metastasis and received anti-tumor therapy again. This case reminds us that any patients with urinary symptoms as well as a history of breast cancer should not be easily ruled out of cancer metastasis. Further examinations or even pathologic biopsy is necessary for these patients.
Because there is still no certain evidence such as randomized clinical trials focusing on male breast cancer patients, treatment approaches are extrapolated from studies of treatment for women breast cancer patients. Adjuvant chemotherapy and HER-2 targeted therapy is suggested for MBC patients who are at substantial risk for recurrence and death since observational cohort studies have suggested improved survival among them[11, 12]. Although no randomized trials have evaluated the role of radiotherapy in men, observational studies have suggested a benefit in men with positive nodes after mastectomy[13, 14]. Endocrine therapy is an important part of male breast cancer management since more than 90% breast cancers in men are hormone-receptor-positive. However, in our case, the patient was a triple negative case with ER (estrogen receptor) negative, PR (progestogen receptor) negative and HER-2 (human epidermal-growth-factor receptor 2) negative, which means that he could only benefit from chemotherapy and radiotherapy.
Genomic tests, such as Oncotype DX, or MammaPrint are increasing used to evaluate the recurrence risk and prognosis for women with breast cancer and the likelihood that chemotherapy benefits. Although these genomic tests are usually recommended for early stage patients to calculate a recurrence score and guide the choice of treatment, we still advised this patient to take a Precitype gene test (immune index and PAM50). This is a next generation RNA-Seq genomic test of 55 genes associating with ER related genes, HER-2 related genes, proliferation related genes and Basal related genes and 17 genes associated with immune genes. Genomic test indicated that this was a Luminal A case and the RNA expression of HER-2 was positive. Since his condition was bad and could not tolerate chemotherapy, we adjusted his therapy schedule with aromatase inhibitors plus gonadotropin-releasing hormone (GnRH) analogue and trastuzumab[17, 18]. However, it seemed that it did not work and his condition was getting poorer. Previous research had demonstrated that those patients would have worse prognosis if their PAM50 molecular subtyping is distinct with immunohistochemical subtyping, which may explain this patient’s poor outcome to some extent. Genomic test such as Oncotype DX is increasingly being used in the management of MBC in clinical practice. However, we need more long-term outcomes data to fully understand the implications of this practice.
We still know very little about MBC at present because of its rather low morbidity rate. More studies about the clinicopathological and immunohistochemical features of MBC should be conducted to build an evidence base that supports future treatment recommendations for this rare disease.