Ileocecal CD5-Positive Diffuse Large B-Cell Lymphoma Presenting with Acute Obstructive Symptoms: A Case Report

Jumpei Kashiwagi, et al.

INTRODUCTION: Primary gastrointestinal lymphoma is a rare form of extranodal non-Hodgkin lymphoma, accounting for approximately 1%–4% of all gastrointestinal malignancies. Among primary gastrointestinal lymphomas, involvement of the small intestine accounts for approximately 20%–30% of cases. CD5-positive diffuse large B-cell lymphoma (DLBCL) is a rare variant, representing approximately 5%–10% of all DLBCL cases and is associated with advanced age, extranodal involvement, and poorer prognosis. We report a rare case of ileocecal CD5-positive DLBCL presenting with acute obstructive symptoms.

Mixed Neuroendocrine–Non-Neuroendocrine Neoplasm of the Esophagogastric Junction with Enteroblastic Differentiation and Morphologic–Immunophenotypic Discordance: A Case Report with Five-Year Disease-Free Survival

Junichi Yoshizawa, et al.

INTRODUCTION: Mixed neuroendocrine–non-neuroendocrine neoplasms (MiNENs) of the esophagogastric junction (EGJ) are extremely rare and are generally associated with aggressive clinical behavior. Enteroblastic (fetal gut-like) differentiation at this anatomical site is uncommon and is regarded as a poor prognostic feature. In addition, discordance between tumor morphology and immunophenotype in such mixed tumors has rarely been documented, and its clinical significance remains unclear. We report an exceptionally rare case of an EGJ MiNEN with enteroblastic differentiation and morphologic–immunophenotypic discordance that achieved long-term disease-free survival after surgery alone.

Spontaneous Jejunal Perforation Caused by Cholesterol Crystal Embolization in a Patient with a Shaggy Aorta: A Case Report

Hiromichi Tanaka, et al.

INTRODUCTION: Cholesterol crystal embolization (CCE) is a systemic disease that is caused by cholesterol crystals and plaque debris that break away from atherosclerotic plaques and most commonly affects the kidneys and skin. Gastrointestinal involvement is uncommon, and perforation of the small intestine is an exceptionally rare and life-threatening complication. The preoperative diagnosis of gastrointestinal involvement is often challenging because symptoms and imaging findings are frequently nonspecific, particularly when contrast-enhanced imaging is contraindicated.

Appendiceal Dieulafoy’s Lesion: A Rare Cause of Lower Gastrointestinal Bleeding

Natsuki Hoshino, et al.

INTRODUCTION: Acute lower gastrointestinal bleeding is common in clinical practice. However, it is rarely caused by the appendix, and cases caused by a Dieulafoy’s lesion are even more uncommon.

Surgical Repair of Posterobasal Ventricular Septal Rupture Complicated by Severe Tricuspid Regurgitation: A Case Report

Masaru Yoshikai, et al.

INTRODUCTION: Posterobasal ventricular septal rupture (P-VSR) developed after acute myocardial infarction (AMI) is often associated with right ventricular infarction and carries a high surgical mortality. The coexistence of tricuspid regurgitation (TR) further aggravates right ventricular dysfunction and right heart failure. Therefore, surgical repair of P-VSR complicated by right ventricular infarction and severe TR is particularly challenging.

Management of Severe Respiratory Failure after Acute Empyema Surgery in a Patient with Down Syndrome: A Case Report

Chisaki Ichinohe, et al.

INTRODUCTION: Empyema associated with parapneumonic pleural effusion can cause respiratory failure requiring surgical intervention. However, some cases remain difficult to manage even after surgery. Patients with Down syndrome are particularly susceptible to respiratory infections and tend to develop more severe symptoms. Few studies have addressed the management of postoperative respiratory failure in acute empyema.

Thoracoscopic Resection of a Bronchial Artery Aneurysm Mimicking Mediastinal Lymph Node Metastasis after Surgery for Papillary Thyroid Cancer: A Case Report

Yoshihiro Shimomura, et al.

INTRODUCTION: Mediastinal lymph node recurrence is frequently encountered during the follow-up after surgery for thyroid cancer. We report a rare case of a bronchial artery aneurysm (BAA) that was preoperatively suspected to be a mediastinal lymph node metastasis based on imaging findings and subsequently treated with thoracoscopic resection.

Full-Thickness Skin Transplantation Combined with Negative-Pressure Wound Therapy for a Refractory Peristomal Large Skin Ulcer Caused by Mucocutaneous Separation: A Case Report

Atsushi Okita, et al.

INTRODUCTION: Stomal mucocutaneous separation is a frequent complication of colostomy, which may complicate wound care due to contamination from fecal leakage, resulting in delayed wound healing. In addition, systemic factors may further influence postoperative wound healing. We report successful combination treatment, involving full-thickness skin graft transplantation and negative-pressure wound therapy (NPWT) in a patient with a large peristomal ulcer that developed progressively in the postoperative course following complete circumferential mucocutaneous separation and infection, which occurred after neoadjuvant chemotherapy followed by laparoscopic abdominoperineal resection.

Axillary Accessory Breast Cancer Performed Reconstruction Using a Local Flap: A Case Report

Sawaka Yukishige, et al.

INTRODUCTION: Accessory breast cancer is rare, with approximately two-thirds of cases arising in the axillary region. Wide local excision is commonly performed; however, large axillary defects can lead to postoperative scar contractures and limited range of motion in the ipsilateral upper limb.

Chest Wall Reconstruction and Chemotherapy for Infectious Costochondritis Associated with Recurrent Breast Cancer

Yuki Katayama, et al.

INTRODUCTION: Management of chest wall recurrence after mastectomy remains debated. While surgery is invasive, both Japanese and international guidelines allow resection in selected patients and complete excision can provide durable control. With advances in systemic therapy, the value of aggressive local treatment for isolated recurrence requires reevaluation. Tumor biology and changes in receptor status after prior therapy also affect prognosis. However, infectious ribs or cartilage ulcers following chemotherapy and chest wall reconstruction are rarely reported. We describe a case of chest wall recurrence treated with multimodal therapy, including resection and reconstruction, complicated by infectious costochondritis.

Fatal Postoperative Interstitial Lung Disease after Neoadjuvant Nivolumab and Complete Resection for Non-Small Cell Lung Cancer: A Case Report

Takatoshi Osako, et al.

INTRODUCTION: Neoadjuvant immunotherapy with nivolumab combined with chemotherapy has become a standard treatment for resectable non-small cell lung cancer (NSCLC), demonstrating improved survival outcomes. However, immune checkpoint inhibitors (ICIs) such as nivolumab are associated with immune-related adverse events, including interstitial lung disease (ILD). While ILD is a recognized complication in advanced NSCLC, its occurrence following neoadjuvant ICI therapy and subsequent surgical resection is rarely reported.

A Case of Mediastinitis Due to Fulminant Group A Streptococcal Infection

Yuta Abe, et al.

INTRODUCTION: Mediastinitis caused by group A Streptococcus (GAS) is extremely rare and often progresses rapidly, with high mortality.