Katsuya Nakai

A case of fibromatosis of the breast.

A 36-year-old woman presented with a 10 mm diameter mass in the right breast. Since the mass persisted for 3 months after detection and mammary carcinoma was suspected based on ultrasonographic findings, the mass was resected. Histologically, the mass demonstrated proliferative margins and consisted of spindle cells with bland cytologic features and abundant collagen. Immunohistochemically, the spindle cells were positive for vimentin and smooth muscle actin, and were negative for cytokeratins and desmin. Furthermore, the cells showed MIB-1 immunoreactivity with a MIB-1 labeling index of 4.1. Based on these findings, was diagnosed fibromatosis. Breast fibromatosis is rare and is usually misdiagnosed as breast carcinoma preoperatively. To date, only 10 cases of breast fibromatosis have been reported in Japan. Among the reported cases in Japan, our patient presented with the smallest mass, and ultrasonographic findings in this case were the same as those of other cases. Our experience and a review of the literature indicated that differentiation of fibromatosis from carcinoma is very dificult by ultrasonographic examination. In our case, despite involvement of the surgical margins, there was no recurrence. This may be attributed to the small size of the mass and focal exposure.

Protein expression and methylation of DNA repair genes hMLH1, hMSH2, MGMT and BRCA1 and their correlation with clinicopathological parameters and prognosis in basal-like breast cancer.

Basal‐like breast cancer (BLBC) is characterized by aggressive behaviour; its genesis is the perturbation of DNA repair as a consequence of BRCA1 methylation or mutation. We comparatively evaluated alterations of DNA repair proteins and p53 between BLBC and non‐BLBC cases.

Differences in Ki67 expressions between pre- and post-neoadjuvant chemotherapy specimens might predict early recurrence of breast cancer

The prognosis of breast cancer patients not obtaining a pathological complete response (pCR) with neoadjuvant chemotherapy (NAC) is poorer than that of pCR patients. Identifying new prognostic factors for non-pCR patients is important because fractions of this population might benefit from novel adjuvant treatments currently under development. High Ki67 expression in remnant disease after NAC has been described as a poor prognostic factor. Studies have shown that a reduction in Ki67 expression is more often observed in good responders to chemotherapy. We hypothesized that the change in Ki67 expression might be useful for predicting patient outcomes and thus retrospectively examined pairs of biopsy and surgical specimens of breast tissue from individual patients. One hundred sixteen patients with remnant invasive disease in the breast, who received NAC and underwent surgery at our institution, were retrospectively examined. Differences in Ki67 expression between pre- and post-NAC specimens were analyzed in relation to patient outcomes. The mean Ki67 expression value after NAC was higher in patients who developed metastasis than in those without metastasis (P<.01). Tumors showing higher Ki67 expression in the surgical than in the biopsy specimen were more frequent in patients with metastasis (P<.01). This trend was more obvious in patients who developed metastasis within 1 year after surgery. Our results indicate that a difference in Ki67 expressions after versus before NAC might be an important predictor of early metastasis. Evaluating not only absolute Ki67 values, but also any changes in response to NAC, may improve the prediction of patient outcomes.

Application of a 70-Gene Expression Profile to Japanese Breast Cancer Patients.

Background: As data on using MammaPrint®, a 70-gene expression profile for molecular subtyping of breast cancer, are limited in Japanese patients, we aimed to determine the gene profiles of Japanese patients using MammaPrint and to investigate its possible clinical application for selecting adjuvant treatments. Patients and Methods: 50 women treated surgically at our institution were examined. The MammaPrint results were compared with the St Gallen 2007 and intrinsic subtype risk categorizations. Results: Of 38 cases judged to be at intermediate risk based on the St Gallen 2007 Consensus, 11 (29%) were in the high-risk group based on MammaPrint. 1 of the 30 luminal A-like tumors (3%) was judged as high risk based on MammaPrint results, whereas 7 of the 20 tumors (35%) categorized as luminal B-like or triple negative were in the low-risk group. There have been no recurrences to date in the MammaPrint group, and this is possibly attributable to most of the high-risk patients receiving chemotherapy that had been recommended on the basis of their MammaPrint results. Conclusions: Our results indicate that MammaPrint is applicable to Japanese patients and that it is of potential value in current clinical practice for devising individualized treatments.