[A Case of Advanced Gastric Cancer Treated with Conversion Surgery followed by Nivolumab Combination Chemotherapy].

The use of nivolumab as first-line therapy for unresectable advanced gastric cancer has now become a standard practice, and its efficacy has been established. This is the first report of a patient with advanced gastric cancer who underwent conversion surgery after first-line nivolumab combination chemotherapy. The patient was a 58-year-old woman. Her medical history included hypertension and dyslipidemia. She had advanced gastric cancer with extensive lymph node metastasis in the left supraclavicular fossa and around the abdominal aorta. After confirming the HER2-negative status and the PD-L1 CPS score to be ≥5, nivolumab was administered in combination with chemotherapy. After the treatment, she underwent a total gastrectomy with D2 dissection, combined splenectomy and pancreatic tail resection for adhesions, and para-aortic lymph node sampling as a conversion surgery. There was no obvious cancerous remnant in the resected specimen, and the pathological response was Grade 3. The patient was alive and recurrence-free at 4 months postoperatively.

[Recurrence-Free Survival after Repeated Resections for Metastatic Inguinal Tumor in Colorectal Mucinous Adenocarcinoma-A Case Report].

A 79-year-old male presented with right inguinal mass and right leg pain. Laparoscopic right hemicolectomy was performed for transverse colon cancer(type 1, muc, pSS, pN1a, pStage Ⅲa)3 years and 6 months ago. We resected the mass located in the spermatic cord and reconstructed it using the Direct Kugel Patch. Histopathological examination revealed mucinous carcinoma and was diagnosed as a metastatic lesion. Local recurrence was detected in the spermatic cord 1 year after resection, and radical inguinal orchiectomy was performed. Six months after the surgery performed for local recurrence, repeated recurrence was detected in the mesh used for reconstruction. Because this recurrence time was short, the patient opted for chemotherapy; however, this resulted in tumor growth, and surgery had to be scheduled. We performed extended resection of the abdominal wall and reconstruction using the fascia lata tensor muscle flap. Although intestinal obstruction, aspiration pneumonia, and skin flap necrosis were observed, the patient was discharged on the 85th postoperative day and remained alive without recurrence for 17 months. Mucinous carcinoma tends to cause local recurrence and requires adequate surgical margin resection. Extended excision should be considered in such cases of repeated local recurrence without distant metastases.

[A Case of Boderline Resectable Pancreatic Cancer Curatively Resected after Chemotherapy with Gemcitabine and Nab-Paclitaxel].

Combination therapy containingnab -paclitaxel(nab-PTX)and gemcitabine(GEM)is widely administered for metastatic pancreatic cancer. Recently, this regimen is likely to be applied for treatment in patients with locally advanced disease or for neoadjuvant chemotherapy(NAC)in patients with borderline resectable(BR)pancreatic cancer. We report a case of BR pancreatic cancer in a patient who was eligible for comparison of the imaging findings with the microscopic findings of the resected specimen. A 72-year-old woman was admitted to our hospital with a complaint of jaundice. Enhanced CT showed a 35mm tumor at the head of the pancreas involvingthe portal vein and in contact with the superior mesenteric artery(SMA). After 4 courses of chemotherapy containinga combination of nab-PTX and GEM, the tumor reduced in size, but was still in contact with the portal vein and SMA on imaging. The level of tumor marker CA19-9 was remarkably reduced. Subtotal stomach-preservingpancreaticoduodenectomy with portal vein reconstruction was performed. Macroscopic findings of the cut surface of the resected specimen showed that a white nodule at the pancreas head involved the portal vein and was in contact with the close-cut margin from the SMA; however, microscopic findings revealed that tumor cells had disappeared in the plexus around the SMA. R0 resection was achieved. The histological treatment effect based on Evans' classification and TNM classification were GradeⅡ and pT3N1aM0(pStage ⅡB), respectively. There has been no recurrence 15 months after the surgery. Based on the abovementioned findings, chemotherapy containing a combination of nab-PTX and GEM can be an effective option of NAC for BR-A pancreatic cancer. Even if the tumor is in contact with the SMA on imaging, when the CA19- 9 level is markedly reduced, there is a possibility of achievingR0 surgery.

[A Case of Pathologically Complete Response of a Rectal Cancer after Preoperative Treatment with mFOLFOX6 and Radiation Therapy].

A 60-year-old man who had bloody stools after sigmoid colonoscopy was admitted to our hospital. A digital examination and sigmoid colonoscopy showed a type 2 circular tumor at location Rb with incomplete mobility and tumor hemorrhage, and the result of a biopsy was moderately differentiated adenocarcinoma (tub2). Computed tomography and magnetic resonance imaging suggested a possibility of invasion of the primary rectal tumor to the sacrum. The clinical stage was cT4bN0M0H0P0, cStage Ⅱ, which is generally not treatable by surgery. Sigmoid colostomy was performed, and a central venous port was implanted. After a preoperative treatment consisting of 3 courses of mFOLFOX6 and radiation therapy, the clinical stage changed to ycT2N0M0H0P0, ycStageⅠ. Super-low anterior resection and covering ileostomy were performed 46 days after the preoperative treatment. A pathological examination revealed no residual cancer cells in the primary lesion and lymph node (Grade 3, pCR). The patient has been disease-free for 4 years and 9 months after the operation.

[A Case of Locally-Advanced Breast Cancer with Liver Metastasis, Treated with Mastectomy of the Primary Tumor after Chemotherapy].

The patient was a 39-year-old woman who was referred to our hospital with suspicion of locally-advanced breast cancer. After several tests, she received a diagnosis of cT4bN1M1 (liver), Stage Ⅳbreast cancer. The liver metastasis was located in S4, and was 1 cm in size. Core needle biopsy was performed on the breast tumor; the pathological diagnosis was invasive ductal carcinoma (scirrhous carcinoma), nuclear Grade (NG) 3, and HER2-positive. She received epirubicin plus cyclophosphamide (EC) followed by docetaxel (DOC) plus pertuzumab (PER) plus trastuzumab (HER). After chemotherapy, the liver metastasis and axillary lymph node metastases had disappeared on imaging findings, showing a complete response (CR), but the primary breast tumor remained, showing a partial response (PR). She underwent mastectomy and axillary lymph node dissection for local control. After surgery, no metastases including liver metastases were seen on CT. The patient is currently receiving tamoxifen and anti-HER2 therapy.