EML4-ALK-positive lung adenocarcinoma has a tendency to express a characteristic morphological pattern. The combined use of morphological feature analysis and immunohistochemistry may be a useful and cost effective screening method for EML4-ALK lung adenocarcinoma.

Purpose: Our recent study revealed that CD55-high population in breast cancer cell line was resistant to apoptosis and formed colonies in vitro more efficiently than CD55-low population. The present study was conducted to examine whether CD55-high population in breast cancer cell line possesses higher tumorigenic potential in vivo and presence of CD55-high cells in breast cancer affects clinicopathologic behavior of patients. Experimental Design: CD55-high and CD55-low population was sorted from breast cancer cell line, injected into immunodeficient mice, and the resultant tumor volume was measured. CD55 expression was immunohistochemically examined in clinical samples from 74 cases with breast cancers, and cases with >1% of tumor cells showing high level of CD55 expression were categorized as CD55 high. Results: The xenotransplanted tumor volume derived from CD55-high population was significantly larger than that from CD55-low population. Fifty (67.6%) of 74 cases of breast cancer were CD55-high. A significant correlation was observed between CD55-high character and relapse rate (P < 0.001). Univariate analysis showed that tumor size (P = 0.005) and CD55 expression (P = 0.005) were unfavorable prognostic factors. Multivariate analysis revealed that the tumor size (P = 0.013) and CD55 expression (P = 0.011) were independent prognostic factors. Conclusions: CD55 play an important role in tumorigenesis of breast cancer, and presence of small population of cells with strong CD55 expression would be sufficient to predict poor prognosis of patients.

Recently, a surgically resected case of intraductal tubulopapillary neoplasm (ITPN) with stromal osseous and cartilaginous metaplasia was encountered. A CT scan showed calcification at the tail of the pancreas two years before the operation. In the resected specimen, macroscopically, the main pancreatic duct was dilated and filled with a whitish solid mass without mucinous material. The tumor showed mainly a solid and papillary growth pattern. The tumor cells had no evidence of acinar differentiation. The tumor cells, at the tail of the pancreas, invaded focally to surrounding pancreatic parenchyma with stromal desmoplastic and fibrosclerotic reaction and also formed nodular stromal osseous and cartilaginous metaplasia. The tumor did not invade extrapancreatic tissue and showed no lymph node metastasis. As there were no signs of chronic calcifying pancreatitis, it is hypothesized that the metaplastic stroma was formed by a stromal reaction due to the tumor growth. It is thought, therefore, that the intraducal component of the tumor had existed at least for two years. This case suggests that ITPN is a relatively indolent tumor with a better prognosis than that of other types of invasive ductal adenocarcinoma of the pancreas.

The patient in this report was a 57‐year‐old man with metastatic non‐small cell lung cancer (NSCLC). After no response to two lines of systemic chemotherapy, he was treated with nivolumab as third‐line therapy, which resulted in a partial response. After 17 months of nivolumab treatment, he developed bone metastasis in his left femur which was treated with radiation therapy. Nivolumab was restarted after radiation therapy. Four months after radiation therapy, he developed another metastatic lesion in the small intestine which was surgically resected. Because there were no recurrent NSCLC lesions after surgical resection, nivolumab was restarted again. At 18 months after surgery, there were no recurrent NSCLC lesions. Immunohistochemical analysis of peritumoral T lymphocytes showed higher expression of T cell immunoglobulin and mucin domain‐containing protein 3 (TIM‐3) and lymphocyte activation gene 3 (LAG‐3) in recurrent lesions of bone and small intestine than in primary lesions. Upregulation of TIM‐3 and LAG‐3 could be associated with mechanisms of adaptive resistance to nivolumab in this case. Here, we report a successful case of continued nivolumab therapy with remission after local treatments consisting of radiation therapy and surgical resection for oligometastases. Continuation of immune checkpoint inhibitor (ICI) treatment may be worth considering if oligometastases can be controlled. Key points Significant findings of the study We report a successful case of continued nivolumab treatment with remission after local treatment (radiation therapy and surgical resection) for oligometastases. What this study adds Upregulation of T cell immunoglobulin and mucin domain‐containing protein 3 and lymphocyte‐activation gene 3 could be associated with mechanisms of adaptive resistance to nivolumab.

Recently, we encountered a biopsy of epithelioid rabdomyosarcoma with lymph node metastasis. A computed tomography (CT) scan showed number of swollen lymph nodes in the left neck and a huge abdominal mass occupying the right kidney. In the lymph node biopsy, tumor cells showed diffuse sheet-like growth reminiscent of carcinoma and melanoma cells with extensive distribution of coagulation necrosis. Tumor cells had abundant amphophilic cytoplasm and clear large nuclei. Most tumor cells showed severe cytologic atypia manifested in prominent nucleoli and pleomorphic nuclei. Tumor cells were focally positive for desmin. Most tumor cells showed expressons for vimentin, BAF47 (INI-1), and myogenin. On reverse transcriptase polymerase chain reaction (RT-PCR) analysis, tumor cells lacked Myo D1 and PAX3/7-FKHR transcripts and showed myogenin transcripts. On cytogenetic (karyotypic) analysis, tumor cells showed highly complex karyotypes. The patient received various regimens of chemotherapy, but 6 months after the biopsy she died with progression of the tumor. Since consent was not obtained, an autopsy was not performed.Electronic supplementary materialThe online version of this article (doi:10.1186/s13000-015-0349-2) contains supplementary material, which is available to authorized users.