The patient was a man in his 70s. He had undergone sigmoid colon resection and D3 dissection 10 years earlier for sigmoid colon cancer and liver metastases. The patient postoperatively received FOLFOX4+bevacizumab(BEV), followed by tegafur/uracil. Increased lymph node metastasis was observed 2 years prior, and treatment with tegafur/gimeracil/oteracil was initiated. However, the tumor continued to grow, and the treatment was switched to CAPOX+BEV. Urinary retention was noted after completing the first oxaliplatin(L-OHP)course. The speed of administration was halved, and a second dose was administered; however, urinary retention occurred again during L-OHP administration, which was therefore discontinued. The treatment was subsequently changed to CAPIRI+BEV, and the urinary retention symptoms resolved. The urinary retention was attributed to acute peripheral neuropathy caused by L-OHP. The absence of urinary retention during the postoperative administration of FOLFOX4+BEV and its onset during the current administration of CAPOX+BEV may have been due to benign prostatic hyperplasia, which developed 5 years prior. Benign prostatic hyperplasia may be a risk factor for urinary retention in patients with acute peripheral neuropathy caused by L-OHP.

A 54-year-old woman was diagnosed with breast cancer and underwent surgery. Postoperative histopathological examination revealed invasive ductal breast carcinoma, pT2pN0(sn)M0, Stage ⅡA, Luminal B, HER2 type. Although the patient underwent postoperative adjuvant therapy, the breast cancer relapsed 4 years post-surgery, and anti-HER2 therapy was initiated. The patient developed brain metastasis, and thus, stereotactic radiation was performed, and trastuzumab-deruxtecan was selected as the third-line treatment. However, on day 8 after the first administration of trastuzumab-deruxtecan, she was coughing and had dyspnea. The patient was diagnosed with trastuzumab-deruxtecan-induced interstitial lung disease. She required endotracheal intubation and steroid therapy during hospitalization, which led to improvement. Here, we describe a case study of complete clinical response to metastasis using post-discharge imaging studies. When administering trastuzumab-deruxtecan, consideration of the possibility of drug-induced lung injury is crucial early in the course of the treatment.

A 70-year-old woman was diagnosed with rectal cancer Ra, cT3N1bM0, cStage Ⅲa. The patient underwent laparoscopic colostomy. Panitumumab+FOLFOX therapy was initiated as preoperative chemotherapy. Four weeks after the administration of panitumumab, micro-ulcerations developed around the stoma, and panitumumab was withdrawn. Eight weeks after treatment, the patient reported redness, swelling, and pain around the stoma. An abscess was observed draining from the ulceration site, and a CT scan revealed extensive subcutaneous abscess formation around the stoma. Because the tumor had shrunk by 50%, chemotherapy was discontinued, and laparoscopic low anterior resection, colostomy closure, and debridement were performed. Postoperatively, the stoma wound was treated with local negative pressure closure. Regular outpatient visits should be encouraged when chemotherapy is administered to ostomates, particularly when anti-EGFR antibody drugs are administered. Because the area where the faceplate is applied can only be observed in detail during stoma care, it is important to identify skin lesions early. Additionally, it is important to collaborate closely with the WOCN, primary care physicians, and dermatologists.

Patients with Trousseau syndrome have been reported to have a poor prognosis when a malignant tumor is concurrently present. Moreover, biopsy can be difficult to perform due to hemorrhage during anticoagulant treatment. We present 2 cases of patients with Trousseau syndrome who were diagnosed with lung cancer using liquid biopsy and document their long-term survival following tyrosine kinase inhibitor treatment.

The patient was in her 50s, had received concurrent chemoradiotherapy for stage ⅢB cervical cancer approximately 19 years ago, and was in good health. She had an ileus 3 months earlier and underwent an experimental laparotomy 2 months before, which revealed cancerous peritonitis, as well as a biopsy of a tumor in the peritoneum. Histological examination revealed malignant peritoneal mesothelioma(MPM). The patient died 2 months postoperatively. Histological examination was the primary diagnostic method, supplemented by HE staining, immunostaining, and genetic testing, for establishing MPM diagnosis. MPM is an extremely rare secondary cancer following cervical cancer treatment.

Trastuzumab deruxtecan(T-DXd)is approved as a second-line treatment for HER2-positive advanced or recurrent breast cancer. Recently, its indication has been expanded to include advanced or recurrent breast cancer exhibiting low HER2 expression and a history of prior chemotherapy. Approximately 45-55% of all breast cancers fall into the HER2-low category, highlighting T-DXd as a promising therapeutic option in the subset. The DESTINY-Breast04 trial demonstrated the efficacy of T-DXd in patients with HER2-low metastatic breast cancer patients who had received one or two prior lines of chemotherapy for advanced or recurrent disease. Here, we present a case of recurrent breast cancer with low HER2 expression in which T-DXd was effective as a ninth-line treatment.

The patient is a 67-year-old female who visited a local clinic with a primary complaint of redness and swelling at the umbilicus. The patient was scheduled for surgical excision because of a suspected umbilical abscess caused by a remnant urachus. During this period, weight loss and elevated tumor marker levels were noted, and further investigation led to the diagnosis of pancreatic body and tail cancer with a Sister Mary Joseph's nodule. Systemic chemotherapy was administered, and initially, both the tumor size and tumor marker levels decreased. However, the tumor subsequently increased in size, and the patient died 7 months after treatment. When an umbilical mass is noted, the possibility of umbilical metastasis from visceral malignancies should be considered.

The aim of this study was to evaluate the outcome and efficacy of hepatic arterial infusion chemotherapy for liver metastasis. Nineteen patients with liver metastasis after esophagectomy for esophageal squamous cell carcinoma underwent hepatic arterial infusion chemotherapy. Six patients(32%)received hepatic arterial infusion chemotherapy as the initial treatment, and the remaining 13 patients(68%)received hepatic arterial infusion chemotherapy after systemic chemotherapy. Of the 13 patients, 3 responders to the first systemic chemotherapy received as maintenance therapy, and 10 non-responders to the first systemic chemotherapy received as a second-line therapy. Response ratio was 37%, and 6 patients(32%)had a toxicity of Grade 3 or more. The median overall survival after liver metastasis was 10.8 months, and the 1-year overall survival rate was 42%. No patient survived more than 3 years after liver metastasis. The 1-year overall survival rate in patients received as the initial and maintenance therapy was 67%, while that in patients received as a second-line therapy was 20%(p=0.0291). Our findings suggested that hepatic arterial infusion chemotherapy for liver metastasis may be effective treatment as the initial therapy or the maintenance therapy for responders to the first systemic chemotherapy.

A 63-year-old female patient was emergently admitted to our hospital with complaints of dyspnea and leg edema. She had a history of abdominal total hysterectomy and bilateral salpingo-oophorectomy for uterine leiomyoma 11 years ago. Computed tomography (CT) and echocardiography revealed a local recurrent tumor on the right side of the inferior vena cava in the retroperitoneal cavity, which extended to the right ovarian vein, inferior vena cava, and right atrium/ventricle. The patient suffered shock due to the tumor lodging in the tricuspid valve, so we performed an emergency intracardiac tumor resection under cardiopulmonary bypass, and two months later, we removed the locally recurrent tumor and the intravascular tumor below the diaphragm. The tumor in the inferior vena cava was removed entirely under hypothermic circulatory arrest. In cases such as this one, which is associated with hemodynamic instability before surgery, it is desirable to aim for a complete resection with a two-stage surgery.

Mediastinal teratomas are germ cell tumors that account for 15% of all adult anterior mediastinal tumors. Giant anterior mediastinal tumors sometimes require a median sternotomy and an additional approach or a clamshell approach. We present a case of a large mature teratoma occupying the left thoracic cavity that was treated by a thoracoscopic surgery with a lateral mini-thoracotomy. Preoperatively, we marked the lateral thoracic area near the largest cyst. In the right lateral recumbent position, a 4-cm incision was made in the left 6th intercostal space. Several large cysts were drained as much as possible. In the supine position, three 5-mm ports were placed in the 2nd, 5th, and 6th intercostal spaces. The left lobe of the thymus and the tumor were resected en block. Pathologically, the tumor was a mature teratoma. The patient had a good postoperative course and was discharged on the 8th postoperative day.

According to the guidelines for thymic tumors, surgical resection is recommended for clinical stage Ⅳ thymic epithelial tumors if completely resectable. A 38-year-old woman presented with fever, chest pain, and back pain. Computed tomography (CT) revealed a mediastinal tumor, which was diagnosed as thymoma type B3 through CT-guided biopsy. Intraoperatively, using 4K three-dimensional (3D) endoscopy, tumor invasion into the left upper lobe and pleural dissemination on the parietal pleura and diaphragm were observed. To preserve the possibility of future re-resection, operation was thoracoscopically performed and the tumor was removed, including partial resection of the left upper lobe. All visible pleural dissemination lesions were also resected, including part of the left diaphragm. The diaphragmatic defect was reconstructed using a Gore-Tex Patch. There is no established treatment strategy for thymoma with incidental pleural dissemination, and the 4K 3D endoscopy may contribute to the successful completion of such a complex operation.

A 67-year-old man was performed total thyroidectomy for stage ⅣC papillary thyroid carcinoma with multiple lymph node and lung metastases. Five years and two months later, treatment with lenvatinib was started. Chest computed tomography (CT) six years and four months after the start of treatment revealed left pleural effusion. A pleural biopsy was performed under thoracoscopy. Histopathological findings showed papillary thyroid carcinoma, and the patient was diagnosed with pleural dissemination of thyroid cancer. Genetic test showed a positive BRAF V600E gene mutation. Treatment with dabrafenib and trametinib was initiated nine days after lenvatinib was discontinued.

Cardiac hemangioma is a rare benign tumor, and the cavernous type accounts for 50~60% of all cardiac hemangiomas. Although most cases are asymptomatic, the risk of serious complications, such as embolism, arrhythmia, tumor rupture, coronary artery obstruction, or sudden death, is high, and surgical resection should be considered. In a 60-year-old woman, follow-up imaging studies after a left breast cancer operation incidentally revealed a cardiac tumor in the right atrium. Transthoracic echocardiography showed a poorly mobile, highly echogenic 12×16 mm mass with clear margins, and contrast-enhanced computed tomography (CT) showed a round tumor with no obvious enhancement. The tumor was resected with an atrial wall and diagnosed as a cavernous hemangioma on histopathological examination. Cardiac hemangiomas are enhanced using contrast medium; however, some cases have no contrast enhancement. Histopathological examination confirmed this diagnosis. The patient was discharged on postoperative day 11 in a good condition.

A 74-year-old male was admitted with acute cholecystitis, during which computed tomography( CT) revealed a 20 cm anterior mediastinal tumor. He developed septic shock requiring tracheostomy and mechanical ventilation, and was referred to our institution. Biopsy under local anesthesia excluded malignant lymphoma and germ cell tumor, leading to planned surgical resection. Due to the tumor's extensive bilateral spread and proximity to the tracheostomy site, clamshell thoracotomy with lower partial sternotomy was performed instead of median full sternotomy. The final diagnosis was well-differentiated liposarcoma. The sternum was closed with wires and plates, and prophylactic negative pressure wound therapy was applied. Postoperatively, there were no sternal complications. Laparoscopic cholecystectomy was later performed, and the tracheostomy cannula was removed successfully. In surgical resection of giant mediastinal tumors, the approach should be selected based on the tumor's location and its extent of invasion into surrounding tissues.

A 42-year-old woman was admitted to our hospital with nodular legions in the bilateral lung. Bilateral lung wedge resection was performed via subxiphoid uniportal approach, and the pathological diagnosis was uterine leiomyoma pulmonary metastasis. At six months after operation, no recurrence was observed.

A male patient in his 70s was admitted with bloody stool. Upper gastrointestinal endoscopy revealed active bleeding from a submucosal lesion located opposite the duodenal papilla. Hemostasis was difficult to achieve, and histopathological analysis of the biopsy specimen revealed only necrotic tissue and inflammatory changes. Endoscopic ultrasonography (EUS) revealed a 35-mm hypoechoic lesion within the submucosal layer. EUS-guided tissue acquisition suggested a poorly differentiated or undifferentiated tumor. Given these findings, the patient underwent pancreaticoduodenectomy. The final diagnosis was primary duodenal epithelioid angiosarcoma.

Small cell carcinoma (SCC) of the prostate has a poor prognosis. We present three cases of primary SCC of the prostate treated with amrubicin as second- or third-line chemotherapy. Case 1 : A 54-year-old male received cisplatin and irinotecan but showed metastatic progression. Amrubicin was initiated as second-line therapy, leading to tumor shrinkage. However, disease progression (PD) occurred in the ninth month, and he passed away 16 months after treatment initiation. Case 2 : An 82-year-old male treated with combined androgen blockade (CAB) later developed pelvic lymph node enlargement, and SCC was diagnosed. He received carboplatin-etoposide and then carboplatin-irinotecan. Amrubicin was given as third-line therapy but showed no significant response. He passed away 24 months after treatment initiation. Case 3 : A 68-year-old male treated with CAB developed M0CRPC and later distant lymph node metastases, confirmed as SCC. He received cisplatin-etoposide and then amrubicin as second-line therapy, achieving a partial response initially but experiencing PD in the fifth month. He passed away 36 months after starting treatment. Amrubicin may be a therapeutic option for primary SCC of the prostate, but achieving prolonged survival remains difficult.

Immune checkpoint inhibitors (ICIs) have shown remarkable efficacy in various malignancies, but their effectiveness in colorectal cancer is generally limited to MSI‒high tumors. We report a case of complete response in an MSI‒stable rectal cancer patient with para‒aortic lymph node metastasis treated with a sequential strategy involving targeted therapy and ICI. A 52‒year‒old woman underwent laparoscopic intersphincteric resection with bilateral lateral lymph node dissection for advanced lower rectal cancer, followed by adjuvant CAPOX. Two years postoperatively, para‒aortic lymph node metastasis was confirmed histologically. FOLFIRI plus cetuximab was initiated, resulting in marked regression of the nodes but without CEA normalization. Switching to FOLFIRI plus bevacizumab led to further CEA reduction. After 2 courses, nivolumab was added and CEA normalized. CEA levels rose again after completion of ICI, but continued FOLFIRI plus bevacizumab led to re‒normalization without radiologic progression. This case suggests that sequential treatment using cetuximab and bevacizumab may modulate the tumor microenvironment and enhance ICI response even in MSI‒stable colorectal cancer. Strategic immunomodulation could provide a promising option for ICI‒resistant tumors.

We report a case of a 51‒year‒old man who presented with right lower abdominal pain. On physical examination, a palpable, tender mass was detected in the right lower abdomen. Contrast‒enhanced computed tomography (CT) revealed a 15‒cm mass in the right lower abdominal wall, supplied by the right inferior epigastric artery, with internal hemorrhage and necrotic areas. Radiological findings were inconclusive for malignancy. As there was no evidence of distant metastasis or invasion into adjacent organs, the tumor was considered resectable, and surgical resection was performed. Histopathological examination confirmed the diagnosis of synovial sarcoma. Given the high risk of recurrence and metastasis associated with synovial sarcoma, adjuvant chemotherapy was administered postoperatively. The patient remains alive without recurrence 1 year after surgery.

We report a case of conversion surgery after nivolumab treatment and chemotherapy for metastatic gastric cancer. A 75‒year‒old man was diagnosed as advanced gastric cancer with peritoneal dissemination. The patient was judged as unresectable gastric cancer and received SOX+nivolumab treatment. After 8 courses of chemotherapy, the primary lesion and enlarged lymph nodes were reduced and abdominal small nodules were disappeared. Consequently, we performed staging laparoscopy followed by laparoscopic distal gastrectomy with D2 lymph node dissection as a conversion surgery. Histopathological diagnosis was ypT2N0M0CY0, and ypStage ⅠB. The patient has been recurrence‒free for 6 months.