アクセイ フクマク チュウヒシュ ニ タイスル cytoreductive surgery

海外では悪性腹膜中皮腫に対してcytoreductive surgery (CRS)と腹腔内温熱化学療法を含めた周術期化学療法が普及しているものの、本邦では悪性腹膜中皮腫に対する外科的治療の報告は乏しい。今回我々は当院でのCRSと周術期化学療法による悪性腹膜中皮腫に対する治療成績を報告する。2013年2月から2022年4月までの期間において、15例の悪性腹膜中皮腫に対してCRSを施行した。患者年齢の中央値は58歳(42-67)で、男性5例と女性10例であった。CRSは病変の存在する壁側腹膜と臓器切除を組み合わせて施行した。10例に対して術前化学療法を施行し、12例に対して術後化学療法を施行した。腹腔内温熱化学療法を8例に対して施行した。全生存期間の中央値は41か月であった。3年生存率57.7%で、5年生存率は34.6%であった。上皮型でperitoneal cancer index≦22であった6例については全例生存中であり、今後の長期生存が期待される結果であった。2.5cmより大きな腫瘍が遺残した場合でも術後化学療法の奏功により3年以上の生存が得られる症例も存在していた。単変量解析をおこなうも、生存に関する統計学的に有意な因子は認めなかった。手術合併症（Clavien-Dindo分類3以上）はGrade 3aが2例、Grade 3bが1例、Grade 4aが2例であった。悪性腹膜中皮腫に対して、これまで日本で施行されてきた化学療法単独療法では予後不良であることが知られている。一方、今回の我々が施行したCRSと周術期化学療法の治療成績は比較的予後良好であり、合併症も許容範囲内であると考えられた。悪性腹膜中皮腫に対する海外におけるCRSと化学療法による良好な治療成績の報告があることからも、本邦でのCRSと周術期化学療法の継続と症例の集積により、体系的な治療法確立と治療成績向上が期待できるであろう。Cytoreductive surgery and perioperative chemotherapy, including hyperthermic intraperitoneal chemotherapy, the standard treatments for malignant peritoneal mesothelioma worldwide are not yet widespread in Japan. We report the surgical outcomes of cytoreductive surgery with perioperative chemotherapy for patients with malignant peritoneal mesothelioma at our institution. We encountered 15 patients who required cytoreductive surgery from February 2013 to April 2022. Their median age was 58 (range 42–67) years, and there were 5 men and 10 women. Cytoreductive surgery was performed by combining extensive peritoneal resection and the resection of various organs. Ten patients underwent neoadjuvant chemotherapy. Hyperthermic intraperitoneal chemotherapy was performed in 8 patients, and 12 patients received postoperative systemic chemotherapy. The median overall survival period was 41 months for all patients. After the cytoreductive surgery, the 3- and 5-year survival rates were 57.7% and 34.6%, respectively. All six patients with epithelial-type peritoneal mesothelioma with a peritoneal cancer index of ≤22 are alive, with expected long-term survival. Furthermore, among patients with a cytoreduction completeness of 3, which indicates residual tumors of >2.5 cm in diameter, long-term survival was achieved in those who responded to chemotherapy. In the univariate analysis, no significant factor was identified for overall survival. For malignant peritoneal mesothelioma, the treatment outcome of chemotherapy alone, which is the standard treatment in Japan, is known to be poor. This study demonstrated that cytoreductive surgery with chemotherapy achieved better outcomes than known reports in Japan. The results of cytoreductive surgery with chemotherapy from across the world may improve treatment outcomes in Japan

Effects of Fiber Diameter and Spacing Size of an Artificial Scaffold on the In Vivo Cellular Response and Tissue Remodeling.

By mimicking the extracellular matrix, nonwoven fabrics can function as scaffolds for tissue engineering application ideally, and they have been characterized regarding their fiber diameter and fiber spacing (spacing size) in vitro. We chronologically examined the in vivo effects of these fabrics on the cellular response and tissue remodeling. Four types of nonwoven polyglycolic acid fabrics (Fabric-0.7, Fabric-0.9, Fabric-3, and Fabric-16 with fiber diameters of 0.7, 0.9, 3.0, and 16.2 μm and spacing sizes of 2.0, 19.3, 19.0, and 825.4 μm, respectively) were implanted into the rat dorsum and subjected to histologic and immunohistochemical analyses from day 3 to 70. With Fabric-0.7, inflammatory cells (mainly M1 macrophages) and myofibroblasts with collagen type III accumulated mainly on the surface of the fabric and did not infiltrate inside the fabric initially, likely due to the narrow fiber space. Massive formation of collagen type I then appeared with the degradation of the fabrics, and finally, the remodeled tissue turned into a dense scar. With Fabric-0.9 and Fabric-3, inflammatory cells (predominantly M2 macrophages) were seen in all layers of the fabric initially. A mild increase in collagen type I was then seen, with few myofibroblasts, and the remodeled tissue ultimately showed a relatively little scar with an adequate thickness of the tissue induced by the fabrics. With Fabric-16, inflammatory cells (predominantly M1 macrophages) infiltrated into all layers of the fabric initially along with many myofibroblasts, especially in the hole. Lately, massive formation of collagen type I was noted due to the slow degradation of the fabric, with the shrinking of the fabric substantially, and the remodeled tissue finally turned to a dense scar. These findings suggest that optimizing the spacing size as well as the fiber diameter of artificial scaffolds may control the cellular response and tissue remodeling and facilitate favorable tissue regeneration without scar formation

Cytoreductive surgery for synchronous and metachronous colorectal peritoneal dissemination: Japanese P classification and peritoneal cancer index

Abstract Aim The outcomes of cytoreductive surgery (CRS) for synchronous and metachronous colorectal peritoneal dissemination were investigated using the Japanese P classification and peritoneal cancer index (PCI). Methods CRS was performed in 111 cases of synchronous peritoneal dissemination and 115 cases of metachronous peritoneal dissemination. The P classification and PCI were determined at the time of laparotomy. Results In the synchronous dissemination group, the 5‐year overall survival rates after CRS in P1/P2 and P3 cases were 51% and 13%, respectively. Even for P3, 51% of the patients achieved macroscopic cytoreductive complete resection (CC‐0), with a 5‐year survival rate of 40%. When P3 cases were classified into PCI 0–9, 10–19, 20–29, and 30–39, CC‐0 was achieved in 93%, 70%, 6%, and 0% of the cases, respectively, and the 5‐year survival rate of PCI 0–9 was 41%. In the metachronous dissemination group, the 5‐year survival rates were 62% for PCI 0–9 and 22% for PCI 10–19; 5‐year survival was not observed in patients with a PCI ≥ 20. CC‐0 was significantly associated with the postoperative prognosis in both synchronous and metachronous peritoneal dissemination. Conclusion In cases of synchronous dissemination, CRS must be performed for P1 and P2 cases or those with a PCI < 10, while detailed examination using PCI is required for P3 cases. In cases of metachronous dissemination, CRS should be considered when the PCI score is <20