The protocol and preliminary baseline survey results of the thyroid ultrasound examination in Fukushima [Rapid Communication].

UNLABELLED: After the Fukushima nuclear power plant accident on March 11, 2011, the public of Japan became particularly concerned about the possibility of an increased risk of childhood thyroid cancer, similar to what was observed after the Chernobyl's accident. Due to serious public health perception, there was an urgency to evaluate the baseline levels of childhood thyroid status in Fukushima prefecture. Therefore we have commenced a thyroid ultrasound examination (TUE) survey of the approximately 360,000 pediatric inhabitants (0 to 18 years of age) who lived in Fukushima at the time of the accident in October 2011. The subjects were divided into three categories according to the standardized diagnostic criteria of ultrasound findings. Category A contained the subjects whose TUE findings were intact or benign. Category B were recommended a confirmatory TUE. Category C was recommended an immediate confirmatory TUE. RESULTS: The survey of 40,302 subjects in the first year was completed in March, 2013. There were 40,097 (99.5%), 205 (0.50%) and 0 subjects in categories A, B and C, respectively. Of the 82 category B subjects who underwent fine needle aspiration cytology (FNAC), 12 were diagnosed with a malignant tumor or were suspected to have malignancy. The 12 subjects received thyroid surgery and 11 thyroid cancers and one benign nodule were confirmed histologically after surgery. This is the first large-scaled TUE survey to employ sophisticated ultrasound screening and aim to evaluate the baseline frequency of childhood thyroid nodules and cysts. The results will become the golden standard of future comparative TUE in Fukushima, Japan.

[Surgical Treatment of Thyroid Cancer].

The strategy for surgical treatment of thyroid cancer differs depending on the histopathological type. In papillary thyroid cancer, which accounts for most cases of thyroid cancer, total thyroidectomy is recommended in high-risk cases with tumors of more than 5 cm or with N1, EX2, or M1 tumors in Japan. On the other hand, ipsilateral lobectomy is performed for low-risk cases with T1N0M0. Our department has also added a treatment policy for the prognostic factor, age. Prophylactic lymph node dissection is performed in the central neck region but is not recommended in the lateral neck region. In follicular thyroid cancer, total thyroidectomy is recommended for widely invasive cancer, and hemithyroidectomy or ipsilateral lobectomy is performed for minimally invasive cancer. When widely invasive cancer is diagnosed after lobectomy, completion thyroidectomy is recommended. Whether minimally invasive follicular cancer with vascular invasion requires completion thyroidectomy is controversial. I also handle medullary thyroid cancer, poorly differentiated thyroid cancer, undifferentiated thyroid cancer, and thyroid malignant lymphoma with a different policy. It is important to balance a surgical treatment strategy with a molecular targeted therapy and radioactive iodine treatment.

[Two cases of rectal NET excised by laparoscopic surgery].

Even if grade 1 neuroendocrine tumors (NET) have low malignant potential, they may still be associated with lymph node metastasis. While the World Health Organization (WHO) classification requires determination of the grade of malignancy and presence of metastasis, it is also useful to evaluate tumor diameter, extent of invasion, and histological characteristics(cell variant, nuclear atypia, and ductal invasion). The authors present 2 cases of rectal NET excised by laparoscopic surgery. Considerations for surgical indications in rectal NET are made based on these case reports.

[Significance of preoperative radiotherapy and lateral lymph node dissection for locally advanced rectal cancer - a comparative study involving different hospitals].

The aim of this study was to compare the results between lateral lymph node dissection (LLND) alone, and preoperative radiotherapy (preRT) followed by LLND, for the treatment of locally advanced rectal cancer. This study assessed 44 consecutive patients with lower rectal cancer (clinical Stages II and III) without lateral lymph node metastasis by preoperative imaging at two hospitals. Twenty-five patients at one hospital received preoperative short-course radiation therapy (total 25 Gy) followed by a curative LLND operation (preRT group), and 19 patients at another hospital underwent a curative operation by LLND alone (non-preRT group). The 5-year locoregional relapse-free survival, disease-free survival, and overall survival rates were not different between the preRT and non-preRT groups. Although three patients in each group had lateral lymph node metastases, none developed pelvic sidewall recurrence. This study suggests that preRT followed by curative surgery with LLND for lower rectal cancers without lateral lymph node metastasis before surgery would not improve survival and local control rates.

[A case of a giant rectal gastrointestinal stromal tumor radically resectable after treatment with neoadjuvant imatinib mesylate].

A 64-year-old male patient was diagnosed with rectal gastrointestinal stromal tumor(GIST)by prostate biopsy, because of high PSA. We considered that a radical operation was impossible because the tumor occupied the pelvis, and we suspected prostate invasion. After neoadjuvant chemotherapy(imatinib mesylate 400 mg/day), the tumor size was reduced(90×85 mm→60×50mm), and we could thus perform radical resection. The patient is currently receiving adjuvant chemotherapy (imatinib mesylate 400 mg/day), without recurrence.

Analysis of Expression of Programmed Cell Death Ligand 1 (PD-L1) and BRAFV600E Mutation in Thyroid Cancer.

In thyroid cancer, it has been suggested that PD-L1 overexpression is associated with some clinicopathological factors and prognosis. The aim of this study is to characterize the expression of PD-L1, the presence of the BRAFV600E mutation, as well as cellular and humoral immunity in thyroid cancer, and to investigate the factors that predict the effectiveness of anti-PD-L1 antibody therapy. Blood samples were collected from 33 patients who were newly diagnosed with thyroid cancer after surgery or biopsy. PD-L1 expression, BRAFV600E mutation, and CD8+ expression were examined by immunohistological staining using clinical thyroid cancer specimens. With a PD-L1 staining cut-off value of 1%, 13 (39.4%) patients were classified as PD-L1 positive. Stimulation Index (SI) is an indicator of T cell activation. PD-L1 expression was significantly correlated with low SI level (p = 0.046). Moreover, BRAFV600E mutation was detected in 24 of the 33 (72.7%) patients, and was significantly associated with PD-L1 expression (p = 0.047). In addition, enhanced CD8+ expression was significantly associated with PD-L1 expression (p = 0.003). Multivariate analyses confirmed that high CRP levels (p = 0.039) were independently and significantly associated with poor progression-free survival. These findings suggest that elevated PD-L1 status can be a prognostic indicator for survival in patients with thyroid cancer when comprehensively assessed using the expression of CD8+, the presence of BRAFV600E mutation and the patient's immune status.

[A case of carcinoma associated with anal fistula in which reconstruction using a gracilis musculocutaneous flap was performed after preoperative chemoradiotherapy].

The patient was a 47-year-old man with a 24-year history of anal fistula. A carcinoma associated with anal fistula was diagnosed after a biopsy was performed because the anal fistula was not improving. Computed tomography and magnetic resonance imaging showed that the tumor had invaded the spongy urethra. Therefore, preoperative chemotherapy(S-1 plus radiation at a dose of 60 Gy/body) was performed. Because the size of tumor decreased, we performed abdominoperineal resection with reconstruction using a gracilis musculocutaneous flap, which enabled the spongy urethra to be fully preserved. Histopathologically, no cancer cells were found to exist on the surgical margin. This case suggested that surgical treatment combined with preoperative chemoradiotherapy may be effective for locally advanced carcinoma associated with anal fistula. Furthermore, improvement of the reconstruction technique for both pelvic and perianal skin defects due to extended resection is an important element of curative surgery.

[A case of metastatic liver carcinoma treated with radiofrequency ablation and hepatectomy].

We report a case of metastatic liver carcinoma treated by radiofrequency ablation (RFA) and hepatectomy. A 53-year-old man suffering from sigmoid colon carcinoma and unresectable multiple liver metastases was treated with capecitabine and oxaliplatin and bevacizumab. After the seventh course, tumor reduction was confirmed but liver dysfunction meant that it was difficult to continue the same regimen. Because preoperative evaluation of liver function showed a high risk of postoperative liver failure, a combination of partial hepatectomy and RFA was planned in order to reduce the amount of liver resection. High anterior resection, partial hepatectomy and RFA were performed as planned. He underwent S-1 therapy following 7 courses of irinotecan, S-1, and bevacizumab therapy. To date, no recurrence has been observed 18 months after the operation. A combination of hepatectomy and RFA is expected to be an effective local treatment for multiple liver metastases of colorectal cancer, although the evidence is currently insufficient.

[Changes in myeloid-derived suppressor cells in malignant effusions of cancer patients following cancer chemotherapy].

Myeloid-derived suppressor cells(MDSCs) have been reported to be induced by inflammation, to suppress immune function, and promote tumor progression, and to be found in circulating blood, tumor tissue, and lymph nodes. MDSCs were found in pleural effusions and ascites of patients with malignant diseases and these results are described in this report. Changes in the levels of MDSCs during clinical responses to cancer chemotherapy are also reported. MDSC levels in malignant effusions have also been shown to change with the levels of MDSCs in peripheral blood and with clinical responses. MDSCs seem to play an important role in inflammation that is strongly related to advancing malignant diseases. The results also suggested that MDSCs may be reduced after effective chemotherapy, which may be effective as an adjuvant treatment with cancer immunotherapy.

[Myeloid-derived suppressor cells in cancer patients].

Myeloid-derived suppressor cells (MDSCs) are one of the major cell populations responsible for regulating immune responses. MDSCs have been reported to accumulate in the blood, lymph nodes, and at tumor sites in most patients during tumor progression and chronic infection, where they potentially suppress T cell functions. We analyzed MDSCs (CD11b+ CD14- CD33+) in peripheral blood mononuclear cells by flow cytometry in 222 patients with esophageal, gastric, colorectal, hepatocellular, cholangiocellular, pancreatic, breast, ovarian, thyroid, and lung cancer, and 18 healthy volunteers. MDSCs were significantly higher in patients with esophageal, gastric, colorectal, hepatocellular, pancreatic, and breast cancer than in healthy volunteers, and the differences were not significant in patients with cholangiocellular, ovarian, thyroid, and lung cancer. Production of the cytokines IFN-γ and IL-6 in response to phytohemagglutinin was assayed using enzyme-linked immunosorbent assay (ELISA) test kits. Serum concentrations of sIL-2R were measured by ELISA. The percentages of MDSCs in patients with colorectal cancer positively correlated with neutrophil counts and the concentration of sIL-2R(both p<0.05), and inversely correlated with the production of IFN-γ( p<0.0001), serum albumin concentration(p<0.005), and lymphocyte counts (p<0.05). These data suggested that MDSCs are strongly related to chronic inflammation and nutritional impairment.

U-to-C RNA editing by synthetic PPR-DYW proteins in bacteria and human culture cells.

Programmable RNA editing offers significant therapeutic potential for a wide range of genetic diseases. Currently, several deaminase enzymes, including ADAR and APOBEC, can perform programmable adenosine-to-inosine or cytidine-to-uridine RNA correction. However, enzymes to perform guanosine-to-adenosine and uridine-to-cytidine (U-to-C) editing are still lacking to complete the set of transition reactions. It is believed that the DYW:KP proteins, specific to seedless plants, catalyze the U-to-C reactions in mitochondria and chloroplasts. In this study, we designed seven DYW:KP domains based on consensus sequences and fused them to a designer RNA-binding pentatricopeptide repeat (PPR) domain. We show that three of these PPR-DYW:KP proteins edit targeted uridine to cytidine in bacteria and human cells. In addition, we show that these proteins have a 5' but not apparent 3' preference for neighboring nucleotides. Our results establish the DYW:KP aminase domain as a potential candidate for the development of a U-to-C editing tool in human cells.

Ectopic expression of MECA-79 as a novel prognostic indicator in gastric cancer.

The aim of this study was to clarify the clinical implications of a unique carbohydrate determinant, MECA-79, in gastric cancer specimens and cells. Immunohistochemical analysis showed that 62 of 225 (27.6%) cases were defined as positive for MECA-79. MECA-79 expression was correlated with depth of invasion, venous invasion, TNM stage, and distant metastasis. In survival analyses, patients with MECA-79 expression had worse prognosis by the log-rank test. Multivariate analysis of the Cox proportional hazard model showed that MECA-79 expression was an independent factor of a worse cancer-specific survival. Among 11 gastric cancer cells, MECA-79 was observed in only MKN7 cells, which also expressed GlcNAc6ST-2 transcript. A knockdown of GlcNAc6ST-2 in MKN7 cells showed a markedly reduced expression of MECA-79, suggesting that GlcNAc-sulfation of MECA-79 is mainly synthesized by GlcNAc6ST-2. Furthermore, real-time RT-PCR analysis revealed that GlcNAc6ST-2 was significantly increased in cancer tissues compared with paired normal mucosa. In conclusion, the expression of MECA-79 could be a useful marker for the prognosis of gastric cancer. Our results might also provide novel perspectives on the biology of MECA-79 and GlcNAc6ST-2 in cancer progression and metastasis.

[PSK decreased FOLFOX4-induced peripheral neuropathy and bone marrow suppression in patients with metastatic colorectal cancer].

FOLFOX4 has been proven to be effective for metastatic colorectal cancer and is now used as a postoperative adjuvant therapy. However, adverse effects such as cold-sensitive paresthesia and bone marrow suppression are common, and this may necessitate a change of chemotherapy regimen even though FOLFOX is effective. PSK, a polysaccharide derived from mushrooms, has been developed in Japan as an immune-enhancing agent, and is widely used in patients with gastric, colorectal and pulmonary cancer. PSK has also been reported to decrease some adverse effects of chemotherapy. FOLFOX4 combined with PSK was administered to patients with metastatic colorectal cancer and the results were evaluated. Eight cycles of FOLFOX4 and PSK (3.0 g/day, po) were given to 25 patients with metastatic (19 hepatic, 3 pulmonary and 3 peritoneal) colorectal cancer. There was no CR (0%), while PR, SD and PD were 48, 36 and 16%, respectively. The response rate was 48%, and the disease control rate was 84%. There were significantly lower frequencies of adverse effects in comparison with published data. Grades 1 and 3 neutropenia occurred in 48 and 24%, respectively, of the patients; grades 1 and 3 nausea in 48 and 4%; and grades 1, 2 and 3 sensory neurotoxicity in 52, 4 and 0%. No patient dropped out due to adverse effect in this study. PSK plus FOLFOX4 seemed to be as effective as FOLFOX4 monotherapy as has been published, and significantly less toxic. These results suggest that this combination therapy may be more effective than FOLFOX4 monotherapy when given over a longer period, with a lower incidence of adverse effects.

[A case of carcinoma associated with anal fistula resected after preoperative chemoradiotherapy].

A 66-year-old man with a 39-year history of anal fistula was admitted to our hospital for anal pain and bleeding. Fistulectomy was carried out for anal fistula. Histological examination of the specimen revealed carcinoma associated with anal fistula. A computed tomography showed that the tumor had invaded the prostate. Therefore, preoperative chemoradiotherapy(S-1 plus radiation 40 Gy/body)for locally advanced cancer was performed. Magnetic resonance imaging showed that the boundary between the tumor and the prostate was unclear, but we performed an abdominoperineal resection and the prostate was fully preserved. Histopathologically, no cancer cell existed on the surgical margin. The histological effect of chemoradiotherapy was judged as grade 2. This case suggested that surgical treatment combined with preoperative chemoradiotherapy may be effective for locally advanced carcinoma associated with anal fistula, in which preservation of adjacent organs is considered to be difficult.

Prospective study on clinical characteristics of Japanese diabetic patients with chronic limb-threatening ischemia presenting Fontaine stage IV.

The aim of this prospective cross-sectional study was to reveal clinical characteristics of Japanese diabetic patients with chronic limb-threatening ischemia (CLTI) presenting ischemic unhealed ulcer/gangrene (Fontaine stage IV) in the real-world settings. The present study included 132 Japanese diabetic patients who underwent endovascular therapy for CLTI presenting Fontaine stage IV. The prevalence of diabetes-related complications, as well as prior history of ankle-brachial index (ABI) measurement before CLTI onset, was evaluated adopting multiple imputation (50 times). Duration of diabetes was referred to as time from diagnosis. The patients were aged 70 ± 10 years, with duration of diabetes 23 ± 12 years. The diabetes-related complications were so common that only 17% (95% confidence interval: 11-24%) and 25% (17-33%) of the population were free from advanced micro- and macroangiopathies, respectively. The clustering of advanced macroangiopathies was not significantly associated with duration of diabetes (P = 0.62). On the other hand, that of advanced microangiopathies was significantly positively associated with duration of diabetes (P = 0.004). However, even in patients with duration of diabetes < 10 years, as many as 63% (38-87%) of patients had at least one advanced microangiopathy. Only 31% (22-39%) of the patients had prior history of ABI measurement before CLTI onset. The history was inversely associated with age (P = 0.005). In conclusion, the advanced diabetes-related complications were highly prevalent, even in those whose diabetes was diagnosed less than a decade before. In addition, only a few patients had ever undergone ABI measurement before CLTI onset.

Rapid repair of human disease-specific single-nucleotide variants by One-SHOT genome editing.

Many human diseases ranging from cancer to hereditary disorders are caused by single-nucleotide mutations in critical genes. Repairing these mutations would significantly improve the quality of life for patients with hereditary diseases. However, current procedures for repairing deleterious single-nucleotide mutations are not straightforward, requiring multiple steps and taking several months to complete. In the current study, we aimed to repair pathogenic allele-specific single-nucleotide mutations using a single round of genome editing. Using high-fidelity, site-specific nuclease AsCas12a/Cpf1, we attempted to repair pathogenic single-nucleotide variants (SNVs) in disease-specific induced pluripotent stem cells. As a result, we achieved repair of the Met918Thr SNV in human oncogene RET with the inclusion of a single-nucleotide marker, followed by absolute markerless, scarless repair of the RET SNV with no detected off-target effects. The markerless method was then confirmed in human type VII collagen-encoding gene COL7A1. Thus, using this One-SHOT method, we successfully reduced the number of genetic manipulations required for genome repair from two consecutive events to one, resulting in allele-specific repair that can be completed within 3 weeks, with or without a single-nucleotide marker. Our findings suggest that One-SHOT can be used to repair other types of mutations, with potential beyond human medicine.

The Clinicopathological Results of Thyroid Cancer With BRAFV600E Mutation in the Young Population of Fukushima.

BACKGROUND: Thyroid ultrasound screening for children aged 0 to 18 years was performed in Fukushima following the accident at the Fukushima Daiichi Nuclear Power Plant. As a result, many thyroid cancer cases were detected. To explore the carcinogenic mechanisms of these cancers, we analyzed their clinicopathological and genetic features. METHODS: We analyzed 138 cases (52 males and 86 females) who had undergone surgery between 2013 and 2016 at Fukushima Medical University Hospital. Postoperative pathological diagnosis revealed 136 (98.6%) cases of papillary thyroid cancer (PTC). RESULTS: The BRAFV600E mutation was detected using direct DNA sequencing in 96 (69.6%) of the thyroid cancer cases. In addition, oncogenic rearrangements were detected in 23 cases (16.7%). Regarding chromosomal rearrangements, 8 (5.8%) RET/PTC1, 6 (4.3%) ETV6(ex4)/NTRK3, 2 (1.4%) STRN/ALK, and 1 each of RET/PTC3, AFAP1L2/RET, PPFIBP/RET, KIAA1217/RET, ΔRFP/RET, SQSTM1/NTRK3 and TPR/NTRK1 were detected. Tumor size was smaller in the BRAFV600E mutation cases (12.8 ±â€…6.8 mm) than in wild-type BRAF cases (20.9 ±â€…10.5 mm). In the BRAFV600E mutation cases, 83 (86.5%) showed lymph node metastasis, whereas 26 (61.9%) of the wild-type BRAF cases showed lymph node metastasis. CONCLUSIONS: The BRAFV600E mutation was mainly detected in residents of Fukushima, which was different from post-Chernobyl PTC cases with RET/PTC3 rearrangement. PTC with the BRAFV600E mutation was smaller but was shown in the high rate of central cervical lymph node metastasis than the wild-type BRAF PTC in the young population of Fukushima.

CD44v6, MMP-7 and nuclear Cdx2 are significant biomarkers for prediction of lymph node metastasis in primary gastric cancer.

The aim of this study was to examine the expression of CD44v6, CD54, Cdx2, CXCL5, Cyclin B1, MMP-7, nm23, RCAS1 and Survivin in primary gastric cancer and to investigate whether these molecules were useful in predicting the lymph node status. They were selected as candidates for indicators of lymph node metastasis from various kinds of cancer-associated genes reported previously. In 135 cases of radically resected primary gastric adenocarcinoma, we investigated the association between the expression of these molecules and clinocopathologic factors by immunohistochemistry. The results revealed that the expression of CD44v6 and MMP-7 were significantly associated with lymph node status. By contrast, nuclear Cdx2 expression was found to be inversely correlated with lymph node metastasis. Moreover, multivariate analysis demonstrated that CD44v6, MMP-7 and nuclear Cdx2 were independent predictors for lymph node status. In conclusion, our results suggest that positive expression of both CD44v6 and MMP-7, and negative expression of nuclear Cdx2 may serve as powerful predictors of lymph node metastasis in gastric cancer. Combined evaluation of these markers could be further useful to predict lymph node status clinically.

Improvement in diagnostic performance of breast cancer: comparison between conventional digital mammography alone and conventional mammography plus digital breast tomosynthesis.

BACKGROUND: The aim of this study was to determine if the diagnostic performance of breast lesion examinations could be improved using both digital breast tomosynthesis (DBT) and conventional digital mammography (CDM). METHODS: Our institutional review board approved the protocol, and patients were provided the opportunity to opt out of the study. A total of 628 patients aged 22-91 years with abnormal screening results or clinical symptoms were consecutively enrolled between June 2015 and March 2016. All patients underwent DBT and CDM, and 1164 breasts were retrospectively analyzed by three radiologists who interpreted the results based on the Breast Imaging Reporting and Data System. Categories 4 and 5 were considered positive, and pathological results were the gold standard. The diagnostic performance of CDM and CDM plus DBT was compared using the mean areas under the receiver operating characteristic (ROC) curves. RESULTS: A total of 100 breast cancer cases were identified. The areas under the ROC curves were 0.9160 (95% confidence interval 0.8779-0.9541) for CDM alone and 0.9376 (95% confidence interval 0.9019-0.9733) for CDM plus DBT. The cut-off values for both CDM alone and CDM plus DBT measurements were 4, with sensitivities of 61.0% (61/100) and 83.0% (83/100), respectively, and specificities of 99.1% (1054/1064) and 98.9% (1052/1064), respectively. CDM yielded 39 false-negative diagnoses, while CDM plus DBT identified breast cancer in 22 of those cases (56.4%). CONCLUSION: The combination of DBT and CDM for the diagnosis of breast cancer in women with abnormal examination findings or clinical symptoms proved effective and should be used to improve the diagnostic performance of breast cancer examinations.

A Case of Squamous Cell Carcinoma of Unknown Primary that Responded to the Multi-Tyrosine Kinase Inhibitor Lenvatinib.

Lenvatinib is an oral tyrosine kinase inhibitor of vascular endothelial growth factor receptors 1, 2, and 3, fibroblast growth factor receptors 1 through 4, as well as platelet-derived growth factor receptor α, RET, and KIT. At present, lenvatinib is used in the treatment of thyroid cancer and renal cell carcinoma. We herein report a case of a 67-year-old patient with squamous cell carcinoma of unknown primary who was effectively treated with lenvatinib. The patient was initially diagnosed as having undifferentiated thyroid cancer, and after total thyroidectomy and bilateral lymph node dissection, lenvatinib was administered for the treatment of residual lymph node metastasis. A computed tomography scan after 1 month of lenvatinib administration showed marked regression of the lymph nodes, but interstitial pneumonia was also detected. Because the drug lymphocyte stimulation test for lenvatinib was strongly positive, we concluded that the interstitial pneumonia was induced by lenvatinib. The interstitial pneumonia only improved by the withdrawal of lenvatinib. Finally, his thyroid tumor was diagnosed as a metastasis of squamous cell carcinoma; however, we were unable to identify the primary lesion. This is the first reported case of interstitial pneumonia induced by lenvatinib.