• ERUS
• SR
• lymph node metastasis
• rectal cancer

• Developing Countries
• Humans
• Lymph Nodes/diagnostic imaging
• Lymph Nodes/pathology
• Lymphatic Metastasis/pathology
• Neoplasm Staging
• Rectal Neoplasms/diagnostic imaging
• Rectal Neoplasms/pathology
• Rectal Neoplasms/surgery
• Retrospective Studies
• Ultrasonography

• local excision
• neoadjuvant therapy
• organ preservation
• radiation
• rectal cancer
• watch and wait

• Local excision
• Rectal cancer
• TAMIS
• TEM

AIM: To investigate the regulatory effect of Vδ1 T cells and the antitumor activity of Vδ2 T cells in rectal cancer.

METHODS: Peripheral blood, tumor tissues and para-carcinoma tissues from 20 rectal cancer patients were collected. Naïve CD4 T cells from the peripheral blood of rectal cancer patients were purified by negative selection using a Naive CD4⁺ T Cell Isolation Kit II (Miltenyi Biotec). Tumor tissues and para-carcinoma tissues were minced into small pieces and digested in a triple enzyme mixture containing collagenase type IV, hyaluronidase, and deoxyribonuclease for 2 h at room temperature. After digestion, the cells were washed twice in RPMI1640 and cultured in RPMI1640 containing 10% human serum supplemented with L-glutamine and 2-mercaptoethanol and 1000 U/mL of IL-2 for the generation of T cells. Vδ1 T cells and Vδ2 T cells from tumor tissues and para-carcinoma tissues were expanded by anti-TCR γδ antibodies. The inhibitory effects of Vδ1 T cells on naïve CD4 T cells were analyzed using the CFSE method. The cytotoxicity of Vδ2 T cells on rectal cancer lines was determined by the LDH method.

RESULTS: The percentage of Vδ1 T cells in rectal tumor tissues from rectal cancer patients was significantly increased, and positively correlated with the T stage. The percentage of Vδ2 T cells in rectal tumor tissues from rectal cancer patients was significantly decreased, and negatively correlated with the T stage. After culture for 14 d with 1 μg/mL anti-TCR γδ antibodies, the percentage of Vδ1 T cells from para-carcinoma tissues was 21.45% ± 4.64%, and the percentage of Vδ2 T cells was 38.64% ± 8.05%. After culture for 14 d, the percentage of Vδ1 T cells from rectal cancer tissues was 67.45% ± 11.75% and the percentage of Vδ2 T cells was 8.94% ± 2.85%. Tumor-infiltrating Vδ1 T cells had strong inhibitory effects, and tumor-infiltrating Vδ2 T cells showed strong cytolytic activity. The inhibitory effects of Vδ1 T cells from para-carcinoma tissues and from rectal cancer tissue were not significantly different. In addition, the cytolytic activities of Vδ2 T cells from para-carcinoma tissues and from rectal cancer tissues were not significantly different.

CONCLUSION: A percentage imbalance in Vδ1 and Vδ2 T cells in rectal cancer patients may contribute to the development of rectal cancer.

• Rectal cancer
• T cells
• Vδ1 T cells
• Vδ2 T cells
• Foxp3
• Cytotoxicity

• CD4-Positive T-Lymphocytes/immunology
• Cell Proliferation
• Cell Separation
• Cells, Cultured
• Coculture Techniques
• Cytotoxicity, Immunologic
• Humans
• Lymphocyte Activation
• Lymphocytes, Tumor-Infiltrating/immunology
• Lymphocytes, Tumor-Infiltrating/metabolism
• Neoplasm Staging
• Phenotype
• Receptors, Antigen, T-Cell, gamma-delta/immunology
• Receptors, Antigen, T-Cell, gamma-delta/metabolism
• Rectal Neoplasms/immunology
• Rectal Neoplasms/metabolism
• Rectal Neoplasms/pathology
• T-Lymphocytes/immunology
• T-Lymphocytes/metabolism
• Time Factors

AIM: To compare the overall survival after local excision or radical resection for early-stage colorectal cancer.

METHODS: Patients who met the criteria were screened from the SEER database between 1998 and 2008, and they were divided into a local excision group and a radical resection group according to the mode of surgery. Each group was further divided into colon or rectal cancer subgroup according to the location of tumor. Kaplan-Meier analysis was performed to determine the overall survival between the two groups and independent prognostic factors.

RESULTS: A total of 13975 cases were included in the study. Of 13647 cases receiving radical resection, 10389 had colon cancer and 3258 had rectal cancer. Of 148 cases receiving local excision, 62 had colon cancer and 86 had rectal cancer. Tumors at T1 stage tended to receive local excision, while tumors at T2 stage were more inclined to accept radical resection (P < 0.001). Univariate survival analysis showed that there were statistical differences between the two groups in 5-year and 10-year survival rates of patients with stage T1 colon cancer, althougn no significant differences were noted in patients with stage T2 colon cancer and those with both stages T1 and T2 rectal cancer. Multivariate survival factor analysis showed that gender, age, race, tumor size, tumor differentiation and mode of surgery were independent prognostic factors, but both colon cancer and rectal cancer had their own characteristics.

CONCLUSION: Local excision can obtain the same survival rate as radical surgery in patients with stages T1 and T2 rectal cancer. Compared to local excision, radical resection can offer better overall survival in patients with stage T1 colon cancer, while more cases are needed to analyze the difference in patients with stage T2 colon cancer.

• Early-stage colorectal cancer
• Local excision
• Radical resection
• Survival study

• Rectal cancer
• lateral spread
• neoadjuvant
• radiotherapy
• restaging
• tumour scatter

Local excision is increasingly performed for “early stage” rectal cancer in the US; however, local recurrence after local excision has become a controversial issue in Western countries. Local recurrence is considered to originate based on the type of tumor and procedure performed, and in surgical margin-positive cases. This review focuses on the inclusion criteria of “early” rectal cancers for local excision from the Western and Japanese points of view. “Early” rectal cancer is defined as T1 cancer in the rectum. Only the tumor grade and depth of invasion are the “high risk” factors which can be evaluated before treatment. T1 cancers with sm1 or submucosal invasion <1,000 μm are considered to be “low risk” tumors with less than 3.2 % nodal involvement, and are considered to be candidates for local excision as the sole curative surgery. Tumors with a poor tumor grade should be excluded from local excision. Digital examination, endoscopy or proctoscopy with biopsy, a barium enema study and endorectal ultrasonography are useful for identifying “low risk” or excluding “high risk” factors preoperatively for a comprehensive diagnosis. The selection of an initial local treatment modality is also considered to be important according to the analysis of the nodal involvement rate after initial local treatment and after radical surgery.

• Rectal cancer
• local excision
• neoadjuvant therapy
• radiotherapy
• transanal excision

Rectal cancer is a distinct subset of colorectal cancer where specialized disease-specific management of the primary tumor is required. There have been significant developments in rectal cancer surgery at all stages of disease in particular the introduction of local excision strategies for preinvasive and early cancers, standardized total mesorectal excision for resectable cancers incorporating preoperative short- or long-course chemoradiation to the multimodality sequencing of treatment. Laparoscopic surgery is also increasingly being adopted as the standard rectal cancer surgery approach following expertise of colorectal surgeons in minimally invasive surgery gained from laparoscopic colon resections. In locally advanced and metastatic disease, combining chemoradiation with radical surgery may achieve total eradication of disease and disease control in the pelvis. Evidence for resection of metastases to the liver and lung have been extensively reported in the literature. The role of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal metastases is showing promise in achieving locoregional control of peritoneal dissemination. This paper summarizes the recent developments in approaches to rectal cancer surgery at all these time points of the disease natural history.