Colorectal cancer (CRC) is one of the most common malignant tumors in China, ranking second in morbidity and fourth in mortality. Metastasis and recurrence are the leading causes of patient death, and the peritoneum is a frequent site of metastasis in CRC, second only to liver and lung metastases. However, the prognosis of peritoneal metastasis is much worse than hepatic and pulmonary metastasis. CRC peritoneal metastasis is challenging early diagnosis, presents with severe symptoms, and has a poor prognosis. It is crucial to emphasize standardized diagnosis and treatment for CRC peritoneal metastasis to improve patients' outcome and enhance their quality of life. This consensus, based on evidence-based medical evidence, revised the "Chinese Expert Consensus on the Diagnosis and Treatment of Colorectal Cancer Peritoneal Metastasis (2022 edition)" and reached a preliminary consensus on the definition, diagnosis, treatment, and prevention of CRC peritoneal metastasis, with the aim of guiding and standardizing the diagnosis and treatment of CRC peritoneal metastasis, developing reasonable and effective comprehensive treatment plans, prolonging survival time and improving quality of life for CRC peritoneal metastasis patients, thereby raising the overall level of diagnosis and treatment for CRC in China.
Humans ; Peritoneal Neoplasms/therapy* ; Colorectal Neoplasms/diagnosis* ; Consensus ; Quality of Life ; Prognosis ; China

Epithelial tumors of the appendix refer to neoplastic lesions originating from the epithelial tissue of the appendix mucosa. These neoplasms exhibit highly heterogeneous pathological features and biological behavior, which contribute to their strong propensity for peritoneal metastasis. Currently, evidence-based medicine regarding appendiceal epithelial neoplasms and the management of their peritoneal metastasis is limited, leading to a lack of standardized clinical practices. To address this, the Professional Committee of Integrated Rehabilitation for Peritoneal Tumors of the Chinese Anti-Cancer Association has organized multidisciplinary experts to focus on key aspects such as the pathological classification of epithelial tumors of the appendix, clinical staging of tumors,the indications for extended resection after local resection, the surgical treatment strategies for concurrent peritoneal metastasis, perioperative rehabilitation, and individualized treatment, while integrating the technical capabilities of relevant specialties. At the same time, it has standardized the perioperative management of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), as well as the clinical application of the pre-rehabilitation system, to enhance the practical operability. Ultimately, the Expert Consensus on the Comprehensive Management of Peritoneal Metastasis from Appendiceal Epithelial Neoplasms (2025 Edition) was developed. This consensus is aimed at further standardizing the systematic diagnosis and treatment process of epithelial tumors of the appendix, thereby reducing the risk of recurrence, improving patient prognosis, and promoting the standardization and homogenization of the diagnosis and treatment of peritoneal metastasis from such tumors.
Humans ; Appendiceal Neoplasms/therapy* ; Peritoneal Neoplasms/therapy* ; Cytoreduction Surgical Procedures ; Consensus ; Hyperthermic Intraperitoneal Chemotherapy

Background: Follicular dendritic cell sarcoma (FDCS) accounts for about 0.4% of soft tissue sarcomas. Approximately onethird of cases occur in extranodal sites and about 28% of extranodal FDCS may metastasize. Intra-abdominal occurrence is rare and there is limited published data to guide oncologists on how to best treat this malignancy. Case Presentation: This is a case of a 33-year-old female who came in due to incidental finding of a left supraclavicular mass with 2-year history of early satiety. Neck node biopsy revealed a poorly differentiated malignant tumor with positive staining for CD21, CD23, vimentin and S100 consistent with FDCS. PET-CT revealed an intensely FDG-avid large mass in the left upper abdomen with signs of necrosis and mass effect. The patient was given three different chemotherapy regimens that included (1) gemcitabine/docetaxel, (2) single agent doxorubicin and (3) ifosfamide/etoposide, but she progressed on all these. Off-label use of bendamustine was then offered and after just the first cycle, the patient reportedly regained strength and was able to get up from wheelchair with noted interval decrease in size of the cervical mass. Unfortunately, the patient deteriorated and succumbed to infection and multiple pulmonary embolisms. Conclusion Intra-abdominal FDCS is a rare malignancy with heterogenous outcomes with no uniform treatment strategy at present. Molecular tumor board discussion and multi-disciplinary approach in extranodal FDCS is important in the diagnosis and management. Patients with multiple poor prognostic factors are at risk for tumor recurrence, metastasis, and death.
Dendritic Cell Sarcoma, Follicular ; Abdominal Neoplasms ; Drug Therapy ; Bendamustine Hydrochloride ; Prognosis

Humans ; Liposarcoma/surgery* ; Retroperitoneal Neoplasms/surgery* ; Neoplasm Recurrence, Local/surgery*

Peritoneal tumours have a large population and a poor prognosis with limited therapeutic options available, and are common originated from gastric, colorectal, appendix and other cancers. Traditionally, peritoneal tumours have long been considered to be a terminal condition with a median survival of 3-6 months, and the palliative symptomatic treatment is recommended. Recently, the multimodal therapeutic strategy of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) has resulted in more effective on the prevention and treatment of peritoneal metastasis, which can significantly improve the survival and quality of life. Under the guidance of the China Anti-Cancer Association (CACA), the "CACA Guidelines for Holistic Integrative Management of Cancer-Peritoneal Tumours" was jointly completed by experts in related fields organized by the Chinese Society of Peritoneal Oncology. This guideline is guided by the concept of integrative medicine and focuses on the domestic epidemiology, genetic background and original studies. It emphasizes the multidisciplinary team to holistic integrative medicine (MDT to HIM), and pays attention to the whole-course management of "prevention, screening, diagnosis, treatment, and rehabilitation". This guideline mainly focuses on peritoneal metastasis from gastrointestinal tumours, aiming to standardize the clinical diagnosis and treatment process, and jointly promote the management of peritoneal metastasis in China.
Humans ; Peritoneal Neoplasms/secondary* ; Combined Modality Therapy ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Quality of Life ; Prognosis ; Hyperthermia, Induced/methods* ; Gastrointestinal Tract ; Colorectal Neoplasms/pathology* ; Cytoreduction Surgical Procedures/methods* ; Survival Rate

Rectal cancer is the most common tumor of digestive tract. For female patients, ovarian metastasis ranks the second place in intraperitoneal organ metastasis. Its symptoms are occult, easily missed and insensitive to systemic treatment, so the prognosis is poor. Surgery is the treatment of choice for patients with rectal ovarian metastases, whether R0 resection is possible or not, and reducing tumor load is associated with better prognosis. With the continuous development of hyperthermic intraperitoneal chemotherapy (HIPEC), tumor reduction can reach the cellular level, which can significantly improve survival. Prophylactic ovariectomy remains a controversial issue in patients at high risk of ovarian metastasis. In this review, we summarize the diagnosis, treatment and prevention strategies of rectal cancer ovarian metastases, hoping to provide some reference for clinical practice.
Humans ; Female ; Colorectal Neoplasms/pathology* ; Hyperthermia, Induced ; Peritoneal Neoplasms/secondary* ; Rectal Neoplasms/therapy* ; Ovarian Neoplasms/therapy* ; Combined Modality Therapy ; Cytoreduction Surgical Procedures

China is a country with a high incidence of gastric cancer, and the majority of patients are in the advanced stage. The peritoneum is the most common site of metastasis and recurrence in advanced gastric cancer. Attention to the standardized diagnosis and treatment of peritoneal metastases of gastric cancer is expected to significantly improve the prognosis and quality of life of some patients. Based on evidence-based medicine and the internationally accepted Delphi method, this consensus revises the Chinese expert consensus on the prevention and treatment of peritoneal metastasis of gastric cancer (2017 edition), reaches a preliminary consensus on the definition, classification, risk factors, diagnosis and prediction, grade assessment, prevention, treatment and management of complications of peritoneal metastasis of gastric cancer, and provides guidance for clinical work.
Humans ; Peritoneum/pathology* ; Peritoneal Neoplasms/therapy* ; Stomach Neoplasms/pathology* ; Consensus ; East Asian People ; Quality of Life ; China

Modern clinical oncology has made great achievements over the last century. However, peritoneal metastasis from gastrointestinal cancer, as one of three most common metastasis modalities, was not re-recognized until the end of the last century, and a normative diagnosis and treatment system has been gradually beginning to be formed until today. This comment is to review the development history, reflect on the lessons and experiences in clinical practice, analyze the difficulties on redefinition, deep understanding and clinical management, and pain points on theory construction, technique practice and discipline construction, in the field of gastrointestinal cancer peritoneal metastasis. We suggested a solution to the difficulties and pain points by realizing the fact of burden of peritoneal metastasis, reinforcing technical training, and promoting collaborative researches, aiming to provide reference for the steady development of peritoneal surface oncology.
Humans ; Peritoneal Neoplasms/secondary* ; Gastrointestinal Neoplasms ; China ; Pain

Peritoneal metastasis is one of the most frequent patterns of metastasis in gastric cancer, and remains a major unmet clinical problem. Thus, systemic chemotherapy remains the mainstay of treatment for gastric cancer with peritoneal metastasis. In well-selected patients, the reasonable combination of cytoreductive surgery, hyperthermic intraperitoneal chemotherapy (HIPEC), and neoadjuvant intraperitoneal chemotherapy with systemic chemotherapy will bring significant survival benefits to patients with gastric cancer peritoneal metastasis. In patients with high-risk factors, prophylactic therapy may reduce the risk of peritoneal recurrence, and improves survival after radical gastrectomy. However, high-quality randomized controlled trials will be needed to determine which modality is better. The safety and efficacy of intraoperative extensive intraperitoneal lavage as a preventive measure has not been proven. The safety of HIPEC also requires further evaluation. HIPEC and neoadjuvant intraperitoneal and systemic chemotherapy have achieved good results in conversion therapy, and it is necessary to find more efficient and low-toxicity therapeutic modalities and screen out the potential benefit population. The efficacy of CRS combined with HIPEC on peritoneal metastasis in gastric cancer has been preliminarily validated, and with the completion of clinical studies such as PERISCOPE II, more evidence will be available.
Humans ; Stomach Neoplasms/pathology* ; Peritoneal Neoplasms/secondary* ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Hyperthermia, Induced/methods* ; Peritoneum/pathology* ; Combined Modality Therapy ; Cytoreduction Surgical Procedures/methods* ; Survival Rate

Peritoneal metastasis of gastric cancer serving as the most frequent form of metastasis, is one of the leading causes of death. A portion of surgically treated patients often suffer from small peritoneal residual metastasis, which will lead to recurrence and metastasis of gastric cancer patients after surgery. Given these, the prevention and treatment of peritoneal metastasis of gastric cancer deserves more attention. Molecular residual disease (MRD) refers to the molecular abnormalities of tumor origin that cannot be found by traditional imaging or other laboratory methods after treatment, but can be found by liquid biopsy, representing the possibility of tumor persistence or clinical progress. In recent years, the detection of MRD based on ctDNA has gradually become a research hotspot in the prevention and treatment of peritoneal metastasis. Our team established a new method for MRD molecular diagnosis of gastric cancer, and reviewed the research achievements in this field.
Humans ; Stomach Neoplasms/pathology* ; Peritoneal Neoplasms/secondary* ; Liquid Biopsy ; Neoplasm, Residual/genetics*