[Update and interpretation of 2021 National Comprehensive Cancer Network (NCCN) "Clinical Practice Guidelines for Bone Tumors"]

Chondrosarcoma of the Sternum: Surgical Challenges, Chest Wall Reconstruction, and Postoperative Management

Although rare, primary chondrosarcoma is the most frequent malignant tumor of the sternum. It commonly manifests as a painful, expanding mass arising from the costochondrosternal junction. Since it is resistant to radiotherapy and chemotherapy, surgical resection with reconstruction is the preferred treatment. A 50-year-old male presented with swelling over the left fourth sternocostal joint, gradually increasing in size. Imaging and clinical assessment suggested an infiltrative neoplasm, and surgical resection was indicated. The patient underwent a partial sternectomy, including a resection of the xiphoid process and costal cartilages two to seven and a partial resection of the manubrium. Postoperative pathohistological analysis specified the change as a low-grade chondrosarcoma in the pT1 stage. Chest wall reconstruction involved three pectus bars fixated around the ribs and the placement of a synthetic polypropylene mesh. The patient required postoperative rehospitalization due to partial skin layer wound dehiscence, serous drainage, and fever. Empirical antibiotic therapy was initiated, and the patient underwent a median superior laparotomy with partial omentoplasty of the sternal region, preserving the mesh and pectus bars. A culture analysis revealed methicillin-resistant Staphylococcus epidermidis, and postoperative antibiotic therapy was adapted to the antibiogram. Subsequently, all parameters of inflammation decreased, and wound healing followed. A one-year follow-up CT scan showed no disease recurrence. This case highlights the intricate surgical management that contributed to the successful treatment of sternal chondrosarcoma. Sternal wound infection, a severe postoperative complication with a high mortality rate, requires prompt identification, precise revision with culture-directed antibiotics, and effort to preserve the prosthetic material.

Case Report: Colon malignant tumor caused by retroperitoneal small round cell undifferentiated sarcoma

Small round cell undifferentiated sarcoma is a rare and highly invasive group of malignant bone and soft tissue tumors, often associated with a high misdiagnosis rate. The patient in this case was a 34-year-old male who presented with a two-month history of abdominal pain that worsened over the past two weeks. Elevated levels of tumor markers CA19-9 and CA72-4 were observed. Imaging revealed a substantial, well-vascularized mass in the lower left abdomen, located in the posterior abdominal cavity, invading the descending colon and the root of the small mesentery, and infiltrating the serous layer. The lesion was extensively resected without any postoperative complications. Microscopic examination indicated a combination of mucinous adenocarcinoma (approximately 30%) and small round cell undifferentiated sarcoma (approximately 70%). The patient was followed up for six months, and one month after surgery, a recurrence of the tumor was observed in the left paracolonic sulcus area, with metastases to the abdominal wall, peritoneum, and medial iliac muscles. Chemotherapy and targeted therapy were administered, and the patient currently survives with the presence of tumors. Small round cell undifferentiated sarcoma is an uncommon and highly invasive tumor, and clinical surgeons need to raise their awareness and realize to the maximum extent possible that this disease can be described through a multi-modal combination of immunohistochemistry and genetic test to improve diagnostic accuracy and reduce missed diagnoses. Further research in the field of biology is necessary to explore targeted drugs specifically suitable for this disease.

Bevacizumab increases the risk of anastomosis site leakage in metastatic colorectal cancer

Background

Bevacizumab is a humanized monoclonal antibody against vascular endothelial growth factor and is used in combination with first-line chemotherapy in the treatment of metastatic colorectal cancer. One of the side effects of bevacizumab is gastrointestinal perforation. This study was designed to identify the effect of bevacizumab in intestinal anastomosis site healing.

Methods

From January 2010 to December 2020, patients diagnosed with stage IV colorectal cancer treated with palliative chemotherapy or chemoradiotherapy followed by radical surgery were retrospectively reviewed. Clinical signs or symptoms and computed tomography were tools used for diagnosing anastomosis site leakage. The patients were divided into two groups, the bevacizumab group (n = 136) and the non-bevacizumab group (n = 124).

Results

Among the 260 patients 14 (5.4%) patients were diagnosed with anastomosis site leakage. In the bevacizumab group, 13 (9.6%) patients were diagnosed with anastomotic leakage. In the non-bevacizumab group, 1 (0.8%) patient was diagnosed with anastomotic leakage. Anastomosis site leakage was significantly higher in the bevacizumab treatment group (P < 0.001). In the bevacizumab group, period of drug discontinuation before surgery was factor associated with anastomosis site leakage in multivariable analysis (P = 0.031).

Conclusion

Stage IV colorectal patients treated with bevacizumab before radical surgery for primary cancer should be carefully observed of anastomosis site leakage after surgery, and the period of drug discontinuation before surgery should be longer than 5 weeks to avoid anastomosis site leakage.

Albumin-Bound Paclitaxel: Worthy of Further Study in Sarcomas

Taxanes (paclitaxel and docetaxel) play an important role in the treatment of advanced sarcomas. Albumin-bound paclitaxel (nab-paclitaxel) is a new kind of taxane and has many advantages compared with paclitaxel and docetaxel. Nab-paclitaxel is currently approved for the treatment of advanced breast, non-small cell lung, and pancreatic cancers. However, the efficacy of nab-paclitaxel in sarcomas has not been reviewed. In this review, we first compare the similarities and differences among nab-paclitaxel, paclitaxel, and docetaxel and then summarize the efficacy of nab-paclitaxel against various non-sarcoma malignancies based on clinical trials with reported results. The efficacy and clinical research progress on nab-paclitaxel in sarcomas are also summarized. This review will serve as a good reference for the application of nab-paclitaxel in clinical sarcoma treatment studies and the design of clinical trials.