Kaori Shigemitsu

Structural requirement of leucine for activation of p70 S6 kinase

The addition of leucine induced activation of p70S6k in amino acid‐depleted H4IIE cells. Whereas the activation of p70S6k by leucine was transient, the complete amino acid stimulated p70S6k more persistently. The effect of leucine on p70S6k was sensitive to rapamycin, but less sensitive to wortmannin. Using various amino acids and derivatives of leucine, we found that the chirality, the structure of the four branched hydrocarbons, and the primary amine are required for the ability of leucine to stimulate p70S6k, indicating that the structural requirement of leucine to induce p70S6k activation is very strict and precise. In addition, some leucine derivatives exhibited the ability to stimulate p70S6k and the other derivatives acted as inhibitors against the leucine‐induced activation of p70S6k.

Evaluation of endoscopic mucosal resection for superficial esophageal carcinoma.

Esophageal superficial carcinoma safely can be resected surgically or endoscopically. We evaluated indications for endoscopic mucosal resection (EMR) and optimal treatment modality for superficial carcinoma of the esophagus based on clinical and pathologic analyses. Between January 1, 1984, and September 30, 1999, 113 patients with superficial cancer of the esophagus underwent surgical or endoscopic resection (n = 33 patients, 36 lesions). The two-channel method, esophageal EMR-tube method or EMR cap-fitted panendoscope was used. Mucosal and submucosal cancers were classified to be epithelial layer (m1), proper mucosal layer (m2), muscularis mucosae (m3), upper third of the submucosal level (sm1), middle third of the submucosal layer (sm2), or the lower third of the submucosal level (sm3) cancers, according to criteria of the Japanese Society for Esophageal Disease. Absolute indication for EMR was restricted to m1 or m2 cancers, and relative indications for EMR included m3 or sml lesions. In our department, indications for EMR were not related to size or circumference of lesions. Lymph vessel invasion and lymph node metastasis markedly increased in lesions that infiltrated the lamina muscularis mucosa (m3). All lesions resected with use of EMR were 0-II (flat), and the depth of invasion in 10 0-IIa or 0-IIb lesions was m1 or m2. Twenty-one 0-IIc lesions were distributed widely from m1 to sm1. All 0-IIa+IIc lesions were m3 or sm1. Preoperative diagnosis accurately was established preoperatively in 61% of patients. Complications related to EMR were detected in 21% of patients and included perforation, stenosis, and hemorrhage. Ten patients also received radiotherapy, chemotherapy, or esophagectomy with lymph node dissection after use of EMR. No such combination therapy was administered in six patients with m3 lesions, but without lymph vessel invasion. All patients treated with use of EMR, including patients with m3 cancer who did not receive additional treatment, are living without recurrence. Local resection with use of EMR could be regarded to be the preferred treatment of superficial esophageal cancers limited to the lamina propria mucosae. Endoscopic mucosal resection also could be regarded to be the preferred treatment of m3 cancer without lymph vessel invasion. Use of additional therapy, such as radiotherapy, allows the use of EMR for m3 cancer with lymph vessel invasion or sm1 cancers.

False-Positive Cases of Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomographic Scans in Metastasis of Esophageal Cancer

Of 129 esophagectomies at our institute from June 2010 to March 2015, we experienced three preoperative positron emission tomography-computed tomographic (PET/CT) false positives. Bone metastasis was originally suspected in 2 cases, but they were later found to be bone metastasis negative after a preoperative bone biopsy and clinical course observation. The other cases suspected of mediastinal lymph node metastasis were diagnosed as inflammatory lymphadenopathy by a pathological examination of the removed lymph nodes. Conducting a PET/CT is useful when diagnosing esophageal cancer metastasis, but we need to be aware of the possibility of false positives. Therapeutic decisions should be made based on appropriate and accurate diagnoses, with pathological diagnosis actively introduced if necessary.

Report of Three Resected Cases of Adenosquamous Carcinoma of the Liver.

肝原発腺表皮癌はまれな疾患であり, 切除例の報告は少ない.今回, 私達は切除しえた肝原発腺表皮癌の3例を経験し, 本疾患の臨床病理学的特徴を検討したので報告する.症例1は57歳の女性で, 左葉切除を行った.腫瘍径は15×13.5×9cmで, 4か月後に残肝再発にて死亡した.症例2は74歳の女性で, 左葉・尾状葉切除を行い, 腫瘍径は7×7×5cmであった.術後11週目に再発死亡した.症例3は68歳の男性.拡大右葉・尾状葉切除, 門脈合併切除を行った.腫瘍径は4×3cmで術後3か月めに骨転移にて死亡した.肝原発腺表皮癌は, 急速に増大する性質を有しており, リンパ節転移をきたしやすく, 予後はきわめて不良で, 治療に難渋することが多い.治療成績の改善に対しては, 今後症例を重ねて検討すべき問題であろう.