Mai Matsumura

Bio: Mai Matsumura is an academic researcher from Yokohama City University. The author has contributed to research in topics: Medicine & Adenocarcinoma. The author has an hindex of 5, co-authored 25 publications receiving 93 citations.

A molecular pathological study of four cases of ciliated muconodular papillary tumors of the lung.

Abstract: Ciliated muconodular papillary tumors (CMPTs) are a recently categorized benign or low-grade malignant neoplasm that develops in the peripheral lung. Only about 40 cases have been reported to date, and the clinicopathological characteristics have yet to be defined in detail. Here, we present four cases of CMPTs with a focus on their immunohistochemical profiles and driver gene mutations. These tumors were a papillary proliferation of a mixture of ciliated, mucous, and basal cells located in the peripheral lung. Ciliated, mucous and basal cells were positive for TTF-1 when using the clone SPT24, but negative for HNF-4α. Basal cells were positive for p40. Mucous cells in some tumors were positive for MUC5AC and MUC6. The Ki-67 index was less than 5%, and strong expression of p53 was not detected. Three of the four tumors had a BRAF (V600E) driver mutation, an EGFR (del E746-T751/S752V) driver mutation, or driver mutations in both EGFR (E709G) and KRAS (G12V). These mutation types are rare for any histological type of lung cancer. The present results confirmed that CMPT is a neoplasm with immunohistochemical features and driver gene mutations that are distinct from those of common lung tumors.

The pathological features of idiopathic interstitial pneumonia‐associated pulmonary adenocarcinomas

Abstract: Aims To investigate the pathological features of idiopathic interstitial pneumonia (IIP) - associated pulmonary adenocarcinoma. Methods Surgically resected adenocarcinomas associated with IIP (the IIP group) and adenocarcinomas without IIP (the non-IIP group) were subjected. We here further focused on adenocarcinomas that developed in the honeycomb lesions. Adenocarcinomas in the IIP group were subdivided into two groups, one group included tumors connected to bronchiolar metaplasia in honeycomb lesions (the H-IIP group) and the other included tumors unrelated to honeycomb lesions (the NH-IIP group). Histomorphological appearance, immunohistochemical expression were compared among the H-IIP group, the NH-IIP group, and the non-IIP group. Results Most of tumor cells in the H-IIP group showed tall columnar shape that displayed similar features to proximal bronchial epithelium, while tumors in the NH-IIP group and the non-IIP group showed club-like shape that displayed similar features to respiratory bronchiole /alveolar epithelium. The cell differentiation markers, thyroid transcription factor-1 (TTF-1) and Hepatocyte nuclear factor 4 alpha (HNF- 4α), tended to be negative for TTF-1 and positive for HNF- 4α in adenocarcinomas in the H-IIP group. The frequency of EGFR mutations was significantly lower in adenocarcinomas in the H-IIP group, although the frequency of KRAS and ALK mutations did not differ among the three groups. Conclusions The IIP-associated pulmonary adenocarcinomas, especially those arising from honeycomb lesions, have distinct pathological features. This article is protected by copyright. All rights reserved.

Intraosseous inflammatory myofibroblastic tumor of the mandible with a novel ATIC-ALK fusion mutation: a case report

Abstract: Inflammatory myofibroblastic tumor (IMT) is a rare low-grade malignant neoplasm with a predilection for children and young adults, and typically arises in the lung, abdominopelvic region, and retroperitoneum. IMTs in the maxillofacial region are extreme rare. Approximately 50% of IMT harbor rearrangements of the anaplastic lymphoma kinase (ALK) gene at 2p23 with various fusion partners. We herein report a case of intraosseous IMT of the mandible with a novel ATIC-ALK fusion. Tooth 43 did not erupt after the loss of tooth 83 in an 11-year-old girl with no previous history of trauma. Panoramic tomography showed a unilocular radiolucent lesion in the right anterior mandible resorbing the root of tooth 42 and the medial side of the root of tooth 44. Computed tomography revealed a well- circumscribed 3-cm osteolytic lesion of the right anterior mandible eroding the buccal cortical plate. The entire lesion was curetted out. A histopathological examination revealed the proliferation of plump spindle cells with a storiform architecture and lymphocytes scattered around spindle cells. The spindle cells showed diffuse cytoplasmic staining for ALK by immunohistochemistry. A fluorescence in situ hybridization analysis revealed the translocation of a part of the ALK gene locus at chromosome 2p23. A rapid amplification of cDNA ends analysis confirmed the rearrangement of ALK and identified ATIC as a partner of this ALK fusion mutant. To the best of our knowledge, this is the first case of intraosseous IMT of the mandible with a novel ATIC-ALK fusion. We also herein reviewed similar tumors reported in the literature.

A Histopathological Feature of EGFR-Mutated Lung Adenocarcinomas with Highly Malignant Potential - An Implication of Micropapillary Element.

Abstract: The purpose of this study was to define histological features determining the malignant potential of EGFR-mutated lung adenocarcinoma (LADC). Surgically resected tumors (EGFR-mutated LADCs with (21) and without (79) lymph node metastasis and EGFR wild-type LADCs with (26) and without (108) lymph node metastasis) and biopsy samples from inoperably advanced tumors (EGFR-mutated LADCs (78) and EGFR wild-type LADCs (99)) were examined. In surgically resected tumors, the EGFR-mutated LADCs with lymph node metastasis had the micropapillary element in a significantly greater proportion than others (Mann-Whitney tests P ≤0.026). The proportion of micropapillary element was higher in the EGFR-mutated LADC at the advanced stage (stage II, III, or IV) than in the tumor at the early stage (stage I) (Mann-Whitney test, P<0.0001). In the biopsy samples from inoperably advanced LADCs (177), EGFR-mutated tumors also had micropapillary element at a higher frequency than EGFR-wild type tumors (53/78 (68%), versus 30/99 (30%), Pearson x2 test, P<0.0001). In stage I EGFR-mutated LADCs (84), the tumors with the micropapillary element (34) exhibited a significantly higher recurrence rate than tumors without micropapillary element (50) (5-year Recurrence-free survival 64.4% versus 93.3%, log-rank test P = 0.028). The micropapillary element may be an exclusive determinant of malignant potential in EGFR-mutated LADC. It is suggested that EGFR-mutated LADC may develop through a distinct histogenesis, in which the micropapillary element is important for promoting progression.

Succinate dehydrogenase B-deficient renal cell carcinoma: A case report with novel germline mutation.

Abstract: Succinate dehydrogenase-deficient renal cell carcinoma (SDH-deficient RCC) is a newly introduced histological type of RCC, which is caused by loss of subunit genes of SDH. It is known to frequently demonstrate familial occurrence and be frequently associated with gastrointestinal stromal tumors and paraganglioma. To date, only 53 cases have been reported. Here, we present an additional case of SDH-deficient RCC occurring in a 40-year-old female. The tumor was histologically biphasic, consisting of tubular and solid architectures. The tumor cells possessed oval nuclei with small nucleoli, and an eosinophilic granular cytoplasm with occasional vacuoles. These cells completely lost the immunohistochemical expression of B subunit of SDH (SDHB). Consequently, the tumor was diagnosed as SDHB-deficient RCC. We identified a novel germ line mutation of the SDHB gene, and also confirmed a hemizygous deletion of the wild-type allele in the tumor cells. To define the pathological characteristics of SDH-deficient RCC, precise diagnosis and accumulation of more cases are required.

Tumors of the Skin

Abstract: Skin tumor is the most intriguing topic for the clinicians. This chapter covers a wide range of issues and provides with informative clues and tips associated with clinical features and pathological presentations and keeps pace with the latest development in molecular biology and immunohistochemistry to assist the readers in the establishment of accurate diagnosis. These following disorders are elaborately selected and arranged from a histopathological perspective.

Energy Metabolism in Cancer: The Roles of STAT3 and STAT5 in the Regulation of Metabolism-Related Genes.

Abstract: A central characteristic of many types of cancer is altered energy metabolism processes such as enhanced glucose uptake and glycolysis and decreased oxidative metabolism. The regulation of energy metabolism is an elaborate process involving regulatory proteins such as HIF (pro-metastatic protein), which reduces oxidative metabolism, and some other proteins such as tumour suppressors that promote oxidative phosphorylation. In recent years, it has been demonstrated that signal transducer and activator of transcription (STAT) proteins play a pivotal role in metabolism regulation. STAT3 and STAT5 are essential regulators of cytokine- or growth factor-induced cell survival and proliferation, as well as the crosstalk between STAT signalling and oxidative metabolism. Several reports suggest that the constitutive activation of STAT proteins promotes glycolysis through the transcriptional activation of hypoxia-inducible factors and therefore, the alteration of mitochondrial activity. It seems that STAT proteins function as an integrative centre for different growth and survival signals for energy and respiratory metabolism. This review summarises the functions of STAT3 and STAT5 in the regulation of some metabolism-related genes and the importance of oxygen in the tumour microenvironment to regulate cell metabolism, particularly in the metabolic pathways that are involved in energy production in cancer cells.