Pembrolizumab response in stage IV luminal-type breast cancer with high microsatellite instability: a case report.

BACKGROUND: Pembrolizumab (PEM), an immune checkpoint inhibitor (ICI), is often used for triple-negative breast cancer, but can also be used to treat solid tumors that exhibit high microsatellite instability (MSI-High). However, patients with breast cancer rarely have MSI-High, the use of PEM in such cases in clinical practice is uncertain due to lack of sufficient supporting data. Here, we report the case of a premenopausal woman in who received PEM for MSI-High luminal-type breast cancer. CASE PRESENTATION: A 40-year-old premenopausal Asian woman was diagnosed with stage IIA (T2N0M0) breast cancer and had an Oncotype DX recurrence score of 38. After surgery, she received 4 courses of chemotherapy with docetaxel and cyclophosphamide. After 3 months of tamoxifen therapy, the patient complained of abdominal pain due to right iliac metastasis, and biopsy of the metastatic lesion showed of luminal type; she was sequentially treated with fulvestrant, a CDK4/6 inhibitor, and an anticancer drug (TS1), but over the next year, metastasis to the bone and para-aortic lymph nodes increased. Tumor was MSI-High; PEM was started, and after three courses, bone metastases were reduced, para-aortic lymph node metastases resolved, opioids were discontinued, and the patient returned to society; PEM was administered for 1 year with no worsening of bone metastases on imaging. Asymptomatic brain metastasis less than 1 cm was detected and gamma knife was performed. Six months after completion of PEM, the patient is working with no new lesions. CONCLUSION: We report a case of luminal-type breast cancer with bone metastases and MSI-High, which was treated with PEM and showed a rapid therapeutic response.

Response-Guided Omission of Anthracycline in Patients with HER2-Positive Early Breast Cancer Treated with Neoadjuvant Taxane and Trastuzumab: 5-Year Follow-Up of Prognostic Study Using Propensity Score Matching.

BACKGROUND: De-escalation therapy omitting anthracycline has been generally adopted for patients with human epidermal growth factor receptor 2 (HER2)-positive early breast cancer in the adjuvant setting, but not in the neoadjuvant chemotherapy (NAC) setting. We investigated whether anthracycline can be omitted in HER2-positive early breast cancer patients receiving neoadjuvant taxane plus trastuzumab with clinical response. METHODS: HER2-positive primary breast cancer patients treated using NAC containing trastuzumab were enrolled between September 2006 and July 2018 at Osaka Breast Clinic. The primary outcome was disease-free survival (DFS). The secondary outcome was overall survival (OS). We investigated survival with or without fluorouracil, epirubicin, and cyclophosphamide (FEC) using the log-rank test and propensity score matching (PSM). RESULTS: In total, 142 patients were retrospectively included and median follow-up was 61 months. There was no significant difference in DFS (p = 0.93) and OS (p = 0.46) between the FEC-omitted group and the FEC-added group. The 5-year DFS was 91% and 88% and OS was 100% and 100%, respectively. After PSM, the FEC-omitted group and the FEC-added group had no significant differences in DFS (p = 0.459) and there were no death events in either group. The 5-year DFS was 90% and 88% and OS was 100% and 100%, respectively. CONCLUSIONS: Using PSM, the 5-year DFS of HER2-positive early breast cancer was not different with or without anthracycline. Response-guided omission of anthracycline may be an option for HER2-positive early breast cancer patients receiving neoadjuvant taxane and trastuzumab with good response in order to avoid overtreatment.

Prognostic Factors in HER2-Positive Primary Breast Cancer Patients Treated Using Neoadjuvant Chemotherapy Plus Trastuzumab.

BACKGROUND: It is unclear for whom new anti-human epidermal growth factor receptor 2 (anti-HER2) agents, such as pertuzumab and T-DM1, should be considered. We investigated prognostic factors before neoadjuvant chemotherapy (NAC) among HER2-positive invasive breast cancer patients and those after NAC among patients who did not achieve pathological complete response (pCR) using conventional adjuvant trastuzumab. METHODS: HER2-positive primary breast cancer patients treated using NAC containing trastuzumab were enrolled between September 2006 and June 2017 at the Osaka Breast Clinic. Patients with distant metastasis or using NAC containing pertuzumab were excluded. The main outcome was disease-free survival (DFS). We investigated pre- and post-NAC prognostic factors using the log-rank test and Cox proportional hazards model. RESULTS: In total, 157 patients were included. Among the pre-NAC prognostic factors, younger age (under 40 years old) and positive clinical nodal status were significantly poorer prognostic factors (hazard ratio [HR] 3.47, 95% CI 1.06-10.12, p = 0.041 and HR 3.32, 95% CI 1.03-14.78, p = 0.045) by multivariate analysis. Among the post-NAC prognostic factors, patients with non-pCR (3-year DFS; 85 vs. 96%, p = 0.022) had a poorer DFS than patients with pCR. DFS was assessed for non-pCR patients (n = 64). High post-NAC Ki-67 status (≥20%; HR 6.73, 95% CI 1.82-31.93, p = 0.004) was a significant and large post-NAC tumor size (≥2 cm; HR 3.65, 95% CI 0.97-14.71, p = 0.056) was a marginally significant prognostic factor by multivariate analysis. After having combined them, high post-NAC Ki-67 status or large post-NAC tumor size was also a significant prognostic factor (HR 5.75, 95% CI 1.32-16.12, p = 0.017). CONCLUSIONS: Positive clinical nodal status and young age were found to be prognostic factors before NAC in HER2-postive invasive breast cancer patients. A high post-NAC Ki-67 status and large post-NAC tumor size were significant and marginally significant prognostic factors, respectively, after NAC in patients who did not achieve pCR. New anti-HER2 agents, such as pertuzumab and T-DM1, should be considered for the patients with those prognostic factors.

[A Case of Advanced Gastric Cancer with Synchronous Liver Metastases Responding to Preoperative Combination Chemotherapy with S-1 plus Oxaliplatin(SOX)].

A 67-year-old man was admitted to our hospital because of anemia and weight loss, and diagnosed with a type 3 tumor in the upper gastric body. Pathological examination suggested moderately differentiated adenocarcinoma with immunohistochemically negative staining for HER2. Abdominal CT revealed thickening of the gastric wall and multiple liver metastases. The clinical findings suggested Stage IV disease(T4aN0M1). Chemotherapy was administered with a combination of S-1 plus CDDP(SP). However, the level of CEA(ng/mL)increased from 49.2 to 634.6, and the treatment schedule was changed to a combination of S-1 plus oxaliplatin(SOX). After 3 courses of the SOX regimen, abdominal CT showed a reduction of liver metastases and the level of CEA decreased to 8.4 ng/mL. We performed total gastrectomy with D1 lymph node dissection in September 2016. Post-operative pathological findings were ypStage IV (T3N0M1)and chemotherapeutic effect was grade 2. CT scan revealed regrowth of the tumor in S2 3 months after the operation. The patient underwent transcatheter arterial chemoembolization(TACE)followed by a regimen of paclitaxel plus ramucirumab(PTX/RAM). At present, he is being treated with the PTX/RAM regimen in the outpatient department with no signs of tumor growth. Although the prognosis of gastric cancer with synchronous liver metastases is very poor, it is possible for survival to be prolonged with multimodality therapy.

[A Case of Successful Repeated Metastectomy for Peritoneal Recurrence of over 90 Years Old Colon Cancer Patient].

Treatment for cancer recurrence in elderly people over 90 years old is usually less advantageous in chemotherapy, and surgical resection is considered rather invasive if cure can be expected. We experienced a case of colon cancer in which recurrence of peritoneal dissemination was discovered and resected at the age of 90 years and at 92 years twice. Laparoscopic surgery for colon cancer at the age of 89 years was performed. At 13 months after primary surgery, CT revealed a nodule of 10mm in diameter in the abdominal cavity, and it was also positive in PET-CT. Because there was no other recurrent foci, radical resection was performed. After 14 months(2 years and 4 months after primary surgery), a 17mm large nodule was pointed out and radical resection was done again. Three years later(5 years and 6 months from primary surgery)have passed, she survives without recurrence at 95-years-old and 4 months without any decline in QOL. When recurrence of peritoneal dissemination can obtain radicality in resection, even for elderly persons, surgery should be considered if invasion is minor.

[Curative Resection for Metastatic Lower Rectal Tumor from Ovarian Cancer - Report of a Case].

We here report the case of a 56-year-old female patient who underwent curative resection for right ovarian cancer with intraperitoneal dissemination and liver metastases. She received following adjuvant chemotherapy, and had been visited hospital for regular follow-up since then. One and half a year after surgery, blood examination showed increasing value of CA125. Contrast-enhanced CT scan revealed a tumor whose long diameter was 5 cm at front side of lower rectum. Following MRI and PET-CT examinations indicated the pelvic tumor as recurrence of ovarian cancer, so that laparotomy was carried out. As the tumor was palped through Douglas cavum, we performed low-anterior rectal resection for en bloc tumor extirpation. Tumor cells mainly developed at peri-rectal wall and proper muscle by HE staining of pathological findings, and ER(positive), vimentin(positive), CD56(positive), synaptophysin(negative)and chromogranin A(negative)by immunostaining indicated the tumor as metastasis of ovarian cancer. Though rectal metastasis from ovarian cancer is basically rare, it might be necessary to rule out possibility of metastatic colon tumor from ovarian cancer when treating patient with rectal tumor who had underwent surgery for ovarian cancer before.

[An 85-Year-Old Man with Lymph Node Metastasis of Recurrent Rectal Cancer Treated UsingProton Beam Therapy].

There are few reports that describe the efficacy of proton beam therapy for lymph node metastasis of recurrent rectal cancer, and carbon ion radiotherapy yields higher local tumor control rates. Proton beam therapy needs a longer treatment period but is less toxic to adjacent healthy organs compared to carbon ion radiotherapy. Here we report an 85-year-old man who underwent curative surgery for rectal and sigmoid cancer at the age of 76 years. After 4 years and 2 months, he had liver metastases at S3 and S8, both of which were resected. Eight years and 6 months after primary resection, CT imaging revealed a solitary lymph node metastasis of 28mm in the minor axis, adjacent to the portal vein and IVC. Because of the location and patient's age, proton beam therapy was selected as the treatment strategy, rather than surgery or chemotherapy. A total of 67.5 GyE/25 fx proton beam therapy was applied. CT imaging 4months after irradiation revealed a partial response(PR)and the tumor had shrunk to 8mm. PR continued for 2 years and 1 month. Although the tumor relapsed after 3 years of irradiation and had grown to 16 mm, the patient had no adverse events or symptoms throughout this period. Proton beam therapy may be one of the options for tumors at difficult locations in fragile patients because of its reduced toxicity.

[A Case of Advanced Rectal Cancer Resulting in a Pathologically Complete Response after Neoadjuvant Chemotherapy].

A 61-years-old man was admitted to our hospital because of abdominal pain. Colonoscopy revealed a type 2 tumor in the rectum, which was diagnosed as low differentiated adenocarcinoma. At least 8 abdominal lymph adenopathies were enhanced on contrast-enhanced CT. We diagnosed stage cT3N2H0M0P0, cStage III b. Because of the risk of a poor prognosis, we tried neoadjuvant chemotherapy for the purpose of down staging. A CRT was prevented by Clostridium difficile enteritis, but we completed 80% of the regimen. Laparoscopic abdominoperineal resection was performed after 4 months of chemotherapy. The specimen contained no tumor lesion, and the pathology results were no residue of adenocarcinoma, status postchemoradiation therapy, Grade 3.

[A Case of T1a Early Gastric Cancer That Metastasized to the Right Femoral Muscles Six Years and Seven Months after Radical Surgery].

A 49-year-old woman presented to our hospital complaining of abdominal distension and right thigh edema 6 years and 7 months after undergoing total gastrectomy for early gastric cancer in December 2008. The histopathological type of the tumor was poorly differentiated adenocarcinoma. The pathological findings led to a diagnosis of T1aN2M0, Stage II A disease. In August 2015, abdominal CT and MRI revealed para-aortic lymph node swelling, ascites, and a tumor on the right femoral muscles. We performed a needle biopsy of the femoral muscle, and the final diagnosis was intramuscular metastasis from the primary gastric cancer. We initiated chemotherapy using TS-1 plus docetaxel. TS-1(80mg/m2/day)was orally administered for 2 weeks followed by a 1-week drug-free period, and 1 course of docetaxel(40mg/m2)was administered intravenously on day 1. After 2 courses of this regimen, the tumor on the right femoral muscles was reduced in size. However, diarrhea and leukopenia were observed, and the treatment schedule was changed to several other chemotherapy regimens. The patient died of progressive disease 6 months after the diagnosis of muscle metastasis. We report a rare case of late recurrence after curative resection in a patient treated for T1a early gastric cancer.

[Right Hemi-Colectomy for a Metastatic Transverse Colon Tumor from Breast Cancer Following Bilateral Breast Cancer Resection - A Case Report].

We herein report the case of a 75-year-old female patient who underwent 4 surgeries for bilateral breast cancer and its recurrence. When she presented at a clinic with an irritable colon, a fist-sized tumor was palpated in the right upper abdomen at her first medical examination. Abdominal CT scan at the clinic revealed a tumor with a maximum diameter of 10 cm on the right side of the transverse colon and multiple swollen mesenteric lymph nodes. Therefore, the patient was referred to our hospital for surgery. Colonoscopy revealed stenosis of the same lesion with an edematous mucosa and sclerosis. Using immunohistochemistry, a biopsy specimen from the lesion tested positive for CK AE1+AE3, and negative for CD20(-)and CD3 (-). As a result, the tumor was diagnosed as a poorly differentiated adenocarcinoma. We performed right hemicolectomy to avoid her intestinal obstruction. Tumor cells were mainly present at the subserosa, according to HEstaining. Using immunostaining, the cells were tested for the following markers: CDX2(-), GCDFP15(weakly positive), CK7(strongly positive), CD20(partially positive), E R(+), PgR(-), and HER2(1+), characterizing the tumor as metastasis of breast cancer. Although gastro-intestinal metastasis from breast cancer is rare, and colon metastasis is even rarer, it might be necessary to rule out the possibility of a metastatic colon tumor from breast cancer when treating patients with a colon tumor who have undergone surgery for breast cancer.

[Long-Term Multidisciplinary Therapy for Multiple Liver Metastases from Colorectal Cancer with Biliary Drainage for Occlusive Jaundice--A Case Report].

Here, we report the case of a 43-year-old man who was diagnosed with sigmoid colon cancer with synchronous multiple liver metastases following resection of a primary lesion. Subsequent mFOLFOX+BV therapy elicited a marked response in the liver metastases, which led to the patient undergoing hepatic (S7) radiofrequency ablation (RFA), hepatic resection (lateral segmentectomy and partial [S5] resection), and cholecystectomy. Six months later, transluminal RFA was repeated because liver (S7) metastasis recurred, and 8 courses of XELOX plus BV therapy were administered. As obstructive jaundice due to recurrence of the liver metastases developed after a 6 months hiatus in chemotherapy, we endoscopically inserted a biliary stent. Despite reducing IRIS plus BV therapy, obstructive jaundice developed again, and 3 intrahepatic biliary stents were inserted with percutaneous transhepatic biliary drainage. To date, the patient has been alive for 4 years since the initial resection of the primary lesion after undergoing consecutive systemic chemotherapy with different regimens. Some studies have shown that in cases of obstructive jaundice caused by advanced gastrointestinal cancer, longer survival could be expected by reducing the severity of jaundice, suggesting that resuming chemotherapy as well as improving the severity of jaundice could contribute to better outcomes. The patient in the present case was successfully treated twice with biliary drainage for occlusive jaundice and chemotherapy, suggesting that a combination of multidisciplinary therapy and adequate local therapy such as biliary drainage could be important for the treatment of metastatic liver cancer.

[A Case of Lymph Node Metastases from Esophageal Cancer Successfully Treated with Weekly Paclitaxel Chemotherapy].

A 61-year-old man underwent a curative operation for advanced esophageal cancer (CT-pT3N2M0, pStage Ⅲ), which had been downstaged with docetaxel, CDDP, 5-FU (DCF) neoadjuvant chemotherapy. Five months after the operation, we diagnosed the patient with recurrence of esophageal cancer with para-aortic lymph node (PALN) metastasis. Systemic chemotherapy was initiated using a regimen of weekly paclitaxel (PTX) administration. After 2 courses, abdominal computed tomography examination indicated regression of the PALN swelling. Eighteen months have passed since the curative operation, and the patient has been doing well with no signs of recurrence. In summary, we successfully treated a case of lymph node metastases from esophageal cancer with weekly PTX chemotherapy.

[A Case of Advanced Gastric Cancer with Synchronous Liver Metastases Treated with Combination Therapy].

A 66-year-old woman was admitted to our hospital because of epigastralgia, and she was diagnosed with a type 2 tumor at the antrum of the stomach. Pathological examination suggested a moderately differentiated adenocarcinoma with negative staining for HER2 on immunohistochemistry. Abdominal CT showed gastric wall thickening and enlarged lymph nodes. Although the clinical finding was Stage ⅢB(T4aN2M0), a liver metastasis (S2) was found during the operation. We performed distal gastrectomy with D2 lymph node dissection and partial hepatic resection in December 2010. A post-operative pathological diagnosis of gastric cancer, pT4aN2M1, pStage Ⅳ, was made. Although adjuvant chemotherapy of S-1 was administered, CT revealed a liver metastasis in S3 5 months after the operation, and the patient underwent transcatheter arterial chemoembolization (TACE) followed by a regimen of S-1 plus CPT-11. After 3 courses of this regimen, grade 2 anorexia was observed, and the treatment schedule was changed to a regimen of capecitabine plus cisplatin (XP). After 7 courses of this regimen, CT revealed multiple liver metastases in S2, S3, and S8, and the treatment schedule was changed to several other chemotherapy regimens. However, liver metastases continued to grow, and the patient died 51 months after surgery. Although the prognosis of gastric cancer with synchronous liver metastases is very poor, it is possible to prolong survival with multimodal therapy.

[A Case of RFA for Liver Metastasis after Resection for Rectal Cancer in a 102-Year-Old Man].

A 100-year-old man was admitted to our hospital because of bloody stool. Colonoscopy revealed a type-2 tumor in the rectum, which was diagnosed as moderately differentiated adenocarcinoma. There was no distant metastasis on CT. After meticulous preoperative evaluation of surgical risks considering his age, laparoscopic high anterior resection was performed. During surgery, the edge of the descending colon showed ischemia; therefore, we performed conversion to open surgery and transverse colon resection. However, the edge of the transverse colon showed ischemia; therefore, ascending colon resection and ascending colon-rectum anastomosis were performed. On day 5 after surgery, the patient developed aspiration pneumonia, for which respirator management was conducted. As his condition improved, he was discharged on postoperative day 32. The pathology results were tub2, pT3, ly0, v2, PM0, DM0, RM0, pN1, Stage Ⅲa. One year 6 months after the surgery, when the patient was 102 years old, CT revealed liver metastasis. RFA was performed for the liver lesion. In people aged 100 years or older, few reports are available on colectomy, and there is no report of treatment for metastasis.

[A case of advanced gastric cancer with portal vein thrombus leading to liver metastases].

A 68-year-old man presenting with anorexia was admitted to our hospital; he was diagnosed with pyloric stenosis arising from a type 3 tumor in the antrum of the stomach. Pathological examination revealed a poorly differentiated adenocarcinoma; immunohistochemical staining tested positive for alpha fetoprotein(AFP), and negative for human epidermal growth factor receptor 2(HER2). Abdominal computed tomography (CT) showed a portal vein thrombus and enlarged lymph nodes. Since the clinical finding was Stage IV(T4aN3M1), curative surgery was ruled out. Following stent placement for food intake, TS-1 plus cisplatin (CDDP) neoadjuvant chemotherapy was initiated. TS-1(80 mg/m² / day) was administered orally for 2 weeks followed by a drug-free 1-week period, and CDDP (60 mg/m²) was administered intravenously on day-1 as 1 course. After 5 courses of this regimen, lymph nodes were reduced in size and the portal vein thrombus disappeared. However, grade 4 thrombocytopenia was observed, and the treatment schedule was modified to include several other chemotherapies. Two years after the initiation of chemotherapy, liver metastasis was detected via elevated AFP. The patient died 27 months after initial treatment. Although the prognosis for gastric cancer with portal vein thrombus is very poor, it is possible to prolong survival with multimodality therapy.

[A case of successful treatment of peritoneal dissemination from gastric cancer with S-1/DOC chemotherapy].

A 66-year-old man underwent a curative operation for advanced gastric cancer (T4aN0M0, Stage IIB). A gastric cancer recurrence with paraaortic lymph node (PALN) metastasis was diagnosed fifteen months after the operation. Systemic chemotherapy was initiated, using a regimen of S-1/CDDP. After 7 courses, abdominal computed tomography (CT) examination indicated the regression of PALN swelling. However, peritoneal dissemination was detected in the neighborhood of the right kidney. S-1/docetaxel (S-1/DOC) was selected as the second-line chemotherapy. After 3 courses, the peritoneal dissemination could not be detected. Five years since the curative operation, the patient has been doing well, with no signs of recurrence. In summary, we successfully treated a case of peritoneal dissemination from gastric cancer with S-1/DOC chemo- therapy.

[A case of long-term survival of advanced gastric cancer with schnitzler metastasis effectively treated with combination chemotherapy].

A 66-year-old woman was diagnosed with unresectable advanced gastric cancer with Schnitzler metastasis in January 2012. She was treated with combination chemotherapy comprising S-1 and docetaxel (DTX). However, in January 2013, after 13 courses of treatment, a computed tomography (CT) indicated peritoneal dissemination growth. The chemotherapy regimen was changed to a combination of S-1 and irinotecan (CPT-11), but after a single course of treatment the patient complained of stomachaches and vomiting. The patient developed ileus from the stenosis of the rectum, and a transanal ileus tube was used to decompress the bowel tract. Due to the patient's poor general condition, a metallic stent was inserted, and she could resume eating. Thereafter, we changed the chemotherapy regimen to weekly paclitaxel (PTX). However, 1 year and 4 months after starting treatment she died of regrowth of the peritoneal disseminating lesions. We recommend a combination of chemotherapy and metallic stent placement to improve quality of life and long-term survival.

[A case of multiple liver metastases after resection of gastrointestinal stromal tumor of the small intestine that was successfully treated with imatinib mesylate].

A 73-year-old man was found to have an intestinal tumor, approximately 10 cm in diameter, on computed tomography (CT). In September 2001, he underwent partial resection of the jejunum with partial colectomy and left nephrectomy. Pathological examination showed 2 mitoses per 50 high-power fields, and immunohistochemical analysis showed positive staining for c-kit. Based on the above findings, the tumor was diagnosed as a high-risk malignant gastrointestinal stromal tumor( GIST) of the small intestine; the patient was followed up and no adjuvant therapy was administered. In October 2005, an abdominal CT scan revealed 2 tumors with diameters of 21 and 28 mm in the S8 and S7 region of the liver, respectively, and the patient was diagnosed with liver metastases from GIST. After obtaining adequate informed consent, chemotherapy with imatinib (400 mg/day) was initiated. Although the patient experienced partial response (PR) 2 months after the treatment, grade 3 neutropenia and general fatigue were observed. Therefore, the treatment schedule was changed to 1 week of therapy, followed by 1 week of rest. At present, at 91 months after the diagnosis of liver metastases, the patient shows no signs of recurrence. Therefore, it is important that adjuvant chemotherapy should be considered for the treatment of patients with high-risk malignant GIST.

[A case of jejunum cancer diagnosed by anemia].

The patient was an 85-year-old woman who was referred to a nearby clinic complaining of shortness of breath. Blood test showed anemia, and she was referred to our hospital for identification of the source of bleeding. Upper and lower endoscopy were performed and revealed no abnormalities. Computed tomography (CT) was performed and showed a >7- cm thickening in the wall of her small intestine. The presence of small bowel cancer was suspected. Oral double-balloon endoscopy was performed and showed a near-circumferential ulcerative lesion in the jejunum that was causing small bowel stenosis. A biopsy yielded a diagnosis of signet-ring cell carcinoma. We performed a partial resection of the patient's jejunum. The histopathological diagnosis of the resected specimen (according to the Union for International Cancer Control [UICC]TNM Classification of Malignant Tumours, seventh edition) was poorly differentiated adenocarcinoma, signet-ring cell carcinoma, mucinous carcinoma, T2 (MP), N0, H0, P0, stage I. 7 months after surgery, the patient is alive without recurrence. The incidence of small intestinal cancer is generally reported to be 1% to 2% of all gastrointestinal malignancies. We report a rare case in which cancer of the small intestine was identified during investigation of anemia.

[Safety and validity of port-less forceps in reduced-port surgery for laparoscopic resection of colorectal cancer].

The purpose of this study was to examine the safety and validity of reduced-port surgery( RPS) in comparison with conventional laparoscopic surgery for colorectal cancer. We investigated 64 cases of colorectal cancer( CRC) resected by laparoscopic surgery at our hospital in 2012, including 22 cases resected by RPS using 1 or more port-less forceps( Endo Relief, Hope Electronics, Japan). With regard to safety, Endo Relief yielded satisfactory outcomes in terms of the limitations of other needlescopic devices, such as lack of strength and risk of tissue injury, while maintaining countertraction. In addition to the original reasons for introducing RPS, such as lessening wound pain and improving the cosmetic outcome after surgery, the advantages of RPS for CRC are high cost efficiency and the possibility of using additional forceps to maintain triangulation or countertraction during laparoscopic surgery. Because it involves a port-less system, RPS facilitates the frequent reuse of forceps, thereby contributing to its high cost efficiency. In the introduction of RPS for laparoscopic colorectal resection, the use of port-less forceps for countertraction could be safe and effective.