Primary adenocarcinoma arising from rectal implantation cyst after low anterior resection for rectal cancer 31 years previously.

Rectal implantation cysts can occur at anastomotic sites after low anterior resection (LAR) for rectal cancer. Herein, we report a case of primary adenocarcinoma arising from a rectal implantation cyst after LAR for rectal cancer. A 70-year-old woman was referred to our hospital for diagnosis and treatment of a growing cystic lesion. She had LAR performed for rectal cancer 29 years previously and had a rectal implantation cyst detected 13 years previously. On the first visit to our hospital, serum CEA and CA19-9 levels were elevated, and computed tomography (CT) scans revealed a cystic lesion near the anastomosis. CT-guided biopsy revealed no cancer tissue in the cystic lesion. After that, the cystic lesion naturally shrank, and serum CEA and CA19-9 levels became normal. Follow-up included 3 monthly serum CEA and CA19-9 testing and 6 monthly CT scans. Two years later, serum CEA and CA19-9 levels were elevated again. Colonoscopy revealed an ulcerative lesion at the anastomotic site, in which adenocarcinoma was confirmed. Abdominoperineal resection with sacral resection was performed, and postoperative histopathological examination revealed a primary adenocarcinoma with mucinous component at the implantation cyst. Since rectal implantation cysts can become malignant after extended periods, clinicians need to be aware of this disease.

Mucin phenotype and genetic alterations in non-V600E BRAF-mutated colorectal cancer.

Colorectal cancer (CRC) is a heterogeneous disease that develops through stepwise accumulation of genetic alterations and progresses via several distinct pathways. However, the tumorigenesis of CRCs with BRAF non-V600E mutations remains unclear. Here, we aimed to elucidate the tumorigenesis of CRCs with BRAF non-V600E mutations, focusing on differences in mucin phenotype and genetic alterations between CRCs with non-V600E and V600E mutations. We investigated 201 patients with CRC and performed panel testing of 415 genes to identify BRAF mutations. Patients were classified into five mucin phenotypes - large-intestinal, small-intestinal, gastric, mixed, and unclassified - using immunohistochemistry for CD10, MUC2, MUC5AC, and MUC6. BRAF mutations were identified in 24 of 201 patients' samples, of which 13 (6.5%) had a V600E mutation (V600E-mutant) and 11 (5.5%) had non-V600E mutations (non-V600E-mutant). MUC5AC expression was significantly associated with V600E mutations (P = 0.040), while CD10 expression was significantly associated with non-V600E mutations (P = 0.010). The small-intestinal mucin phenotype was significantly associated with non-V600E mutations (P = 0.031), while the mixed mucin phenotype was significantly associated with V600E mutations (P = 0.027). Regarding genetic alterations, focusing on the WNT signaling pathway, APC mutation was significantly associated with non-V600E mutations (P < 0.001), while RNF43 mutation was significantly associated with V600E mutations (P = 0.020). Considering the differences in mucin phenotype and genetic alterations, different modes of tumorigenesis are assumed for CRC with BRAF V600E mutation and non-V600E mutations. These findings are important in understanding the biology and treatment strategies for BRAF-mutant CRC.

Conversion therapy with pembrolizumab for a peritoneal metastasis of rectal cancer causing hydronephrosis in a patient with Lynch syndrome.

A 44-year-old woman with Lynch syndrome was referred to our hospital for treatment of recurrence of microsatellite instability-high rectal cancer. [18F]Fluorodeoxyglucose (18FDG)-positron emission tomography revealed a peritoneal metastasis with invasion to the small intestine and left ureter. The peritoneal metastasis was diagnosed initially as unresectable because of extensive invasion to the left ureter requiring nephrectomy. Hence, first-line treatment with pembrolizumab was started. After the first course of pembrolizumab, she developed hydronephrosis and a resulting urinary tract infection (UTI). A percutaneous nephrostomy was performed to control the UTI. After six courses of pembrolizumab, 18FDG-positron emission tomography showed that the peritoneal metastasis was smaller with significantly reduced 18FDG uptake, and it was then diagnosed as resectable without nephrectomy. She underwent R0 resection of the peritoneal metastasis with partial resection of the small intestine. Intraoperatively, the peritoneal metastasis showed no invasion of the left ureter, allowing its preservation. The percutaneous nephrostomy was removed postoperatively, and she has not developed any subsequent UTIs. Histopathologically, the tumor showed a pathological complete response to pembrolizumab. To the best of our knowledge, this is the first case of conversion therapy with pembrolizumab for peritoneal metastasis with hydronephrosis.

[Long-Term Survival after Liver and Pulmonary Metastasectomy Following Chemotherapy for Metastatic Pancreatic Ductal Adenocarcinoma-A Case Report].

The patient was a 61-year-old man with a diagnosis of carcinoma of the pancreatic head. Abdominal computed tomography( CT)showed no distant metastasis, and he underwent subtotal stomach-preserving pancreatoduodenectomy. Immediately after surgery, he received liver perfusion chemotherapy with 5-fluorouracil followed by systemic gemcitabine. Eighteen months after surgery, CT revealed liver metastasis in the S6 segment, and partial hepatectomy was performed. The pathological diagnosis was liver metastasis of pancreatic cancer. Postoperatively, the patient was treated with gemcitabine and S-1 therapy for 1 year and then switched to S-1 monotherapy for about 6 months. Four years after the initial surgery, CT showed 2 metastases in the right lung. After 2 months of S-1 monotherapy, wedge resection of the upper and lower lobes of the right lung was performed. Gemcitabine and nab-paclitaxel therapy were administered, after the metastasectomy, but pleural dissemination appeared on CT 5 years after the initial surgery. Modified FOLFIRINOX therapy was started and continued for 8 months, but CT revealed further disseminated lesions in the diaphragm. Palliative irradiation was provided, but the disease gradually progressed. After multidisciplinary treatment, the patient survived for 6 years and 3 months after the initial surgery.

Axillary cutaneous metastasis of colon cancer with microsatellite instability-high and BRAF V600E mutation treated with curative-intent surgery: a case report.

BACKGROUND: Colorectal cancer (CRC) metastasizes to various organs, while cutaneous metastases are rare. Although there have been several previous reports of axillary cutaneous metastases with other metastases of CRC, there has never been a report of axillary cutaneous metastasis of CRC that could be treated with curative-intent surgery. CASE PRESENTATION: A 68-year-old female was diagnosed with an axillary cutaneous tumor and ascending colon cancer with invasion to the duodenum. Histopathological and immunohistochemical analysis revealed that the axillary cutaneous tumor showed adenocarcinoma and the same expression pattern for cytokeratin 7, cytokeratin 20, and CDX2 as the ascending colon cancer, and that proved to be KRAS-NRAS wild type, MSI-H, and with a BRAF V600E mutation. The patient underwent a two-stage resection with curative intent after receiving neoadjuvant chemotherapy which consisted of one cycle of modified FOLFOX6 followed by two cycles of FOLFOXIRI. During and after the two operations, the patient received a total of nine cycles of modified FOLFOX6 as adjuvant chemotherapy. Two years after the initial surgery, and 1 year and 8 months after the second surgery, the patient is alive without recurrence. CONCLUSIONS: To the best of our knowledge, this is the first report of axillary cutaneous metastasis of CRC with microsatellite instability-high and BRAF V600E mutation that could be treated with curative-intent surgery. It is important to recognize the presence of such cases for the accurate diagnosis and treatment of CRC with cutaneous metastasis.

Clinical significance of metastatic tumor deposit foci in rectal cancer in the lateral pelvic lymph node area.

BACKGROUND: Although previous studies have demonstrated that tumor deposits (TDs) are associated with worse prognosis in colon cancer, their clinical significance in rectal cancer has not been fully elucidated, especially in the lateral pelvic lymph node (LPLN) area. This study aimed to clarify the clinical significance of TDs, focusing on the number of metastatic foci, including lymph node metastases (LNMs) and TDs, in the LPLN area. METHODS: This retrospective study involved 226 consecutive patients with cStage II/III low rectal cancer who underwent LPLN dissection. Metastatic foci, including LNM and TD, in the LPLN area were defined as lateral pelvic metastases (LP-M) and were evaluated according to LP-M status: presence (absence vs. presence), histopathological classification (LNM vs. TD), and number (one to three vs. four or more). We evaluated the relapse-free survival of each model and compared them using the Akaike information criterion (AIC) and Harrell's concordance index (c-index). RESULTS: Forty-nine of 226 patients (22%) had LP-M, and 15 patients (7%) had TDs. The median number of LP-M per patient was one (range, 1-9). The best risk stratification power was observed for number (AIC, 758; c-index, 0.668) compared with presence (AIC, 759; c-index, 0.665) and histopathological classification (AIC, 761; c-index, 0.664). The number of LP-M was an independent prognostic factor for both relapse-free and overall survival, and was significantly associated with cumulative local recurrence. CONCLUSION: The number of metastatic foci, including LNMs and TDs, in the LPLN area is useful for risk stratification of patients with low rectal cancer.

[A Case of Appendiceal Carcinoma with BRAF V600E Mutation and Microsatellite Instability-High].

A 75-year-old woman presented to our hospital with abdominal pain and melena. Colonoscopy revealed an ulcer at the appendiceal orifice. Histopathological examination of biopsy specimens revealed adenocarcinoma. Computed tomography showed an appendiceal mass of 11.8×6.7 cm in size involving the cecum and terminal ileum without any distant metastatic findings. Ileocecal resection with regional lymph node dissection to the root of the ileocolonic artery was performed. Histopathological examination of the specimen revealed appendiceal adenocarcinoma. Molecular subtype of the tumor was BRAF V600E mutation and microsatellite instability-high(MSI-H). The pathological stage was pT4bpN1bcM0, pStage ⅢC. She received 8 courses of CapeOX as adjuvant chemotherapy and no recurrence was noted 12 months following the surgery. The establishment of standard treatment strategies including surgery, chemotherapy, and immunotherapy for carcinoma of the appendix with BRAF V600E mutation and/or MSI-H is needed.

[Cancer of the Ascending Colon and Left Breast in an Older Adult Complicated by Thoracic Aortic Aneurysm].

An 87-year-old woman with a gradually enlarging mass in her left breast, diagnosed as having left-sided breast cancer with skin invasion by a local practitioner, was referred to our hospital. Computed tomography revealed ascending colon cancer with abdominal wall invasion and a thoracic aortic aneurysm(Stanford type B), in addition to breast cancer with skin invasion. A thoracic endovascular aortic repair and bypass surgery between the subclavian arteries were both performed for the thoracic aortic aneurysm. After 6 days, a right hemicolectomy and D2 lymphadenectomy were performed for the ascending colon cancer. A postoperative pathological diagnosis of pT3N0M0, pStage Ⅱa, was made. A total left mastectomy with a full-thickness skin graft for left breast cancer was performed after 2 months following the ascending colon cancer surgery. The postoperative pathological diagnosis was pT3N0M0, pStage ⅡB. No evidence of local recurrence or distant metastasis of the ascending colon cancer has been observed at 20 months postoperatively, or of the breast cancer after 18 months following surgery.

[A Case of Esophageal Carcinoma with Tracheal Invasion after Preoperative Treatment with Docetaxel, Cisplatin, and 5-Fluorouracil in Which Definitive Chemoradiotherapy and Salvage Esophagectomy Prolonged Survival].

A 57-year-old man was diagnosed as having resectable advanced esophageal carcinoma adjacent to the trachea(Ut, cT3N0M0)and received preoperative docetaxel, cisplatin, and 5-fluorouracil therapy. Due to tracheal tumor invasion and upstaging to cT4bN0M0 after 1 course of chemotherapy, the treatment was converted to definitive chemoradiotherapy (CRT). A remarkable response with no evidence of tracheal invasion was observed on computed tomography following definitive CRT. He underwent successful curative resection with salvage esophagectomy, and the resected tumor was staged as pT1bN0M0. No adjuvant therapy was administered, and the patient was alive with no evidence of disease at the 5-year postoperative follow-up. The response to preoperative treatment should be meticulously assessed and appropriate treatment modalities used to avoid overlooking the potential for cure, even if the response to preoperative treatment with docetaxel, cisplatin, and 5-fluorouracil is poor.

Gene panel testing detects important genetic alterations in ulcerative colitis-associated colorectal neoplasia.

Ulcerative colitis-associated neoplasia (UCAN) harbors unique genetic alterations and mutational tendencies. The clinical application of gene panel testing enables precision medicine by tailoring treatment to individual gene alterations. We hypothesized that gene panel testing may detect clinically important genetic alterations in UCAN, with potential usefulness for the diagnosis and treatment of UCAN. In the present study, gene panel testing was used to identify genetic alterations in UCAN, and the possibility of clinical utility of gene panel testing in UCAN was investigated. The present study included 15 patients with UCAN, and gene panel testing was performed to identify genetic alterations associated with diagnosis and treatment. Genetic alterations of UCAN were compared with those of 203 patients with sporadic colorectal cancer (CRC). APC and PTEN mutations were less frequent, while RNF43 frameshift or nonsense mutations were more frequent in UCAN compared with sporadic CRC. TP53 mutations were identified in 13/15 patients (87%) with UCAN. Notably, 4/15 patients (27%) with UCAN had no genetic alterations other than TP53 mutation, while this occurred in 1/203 patients (0.5%) with sporadic CRC (P<0.001). Microsatellite instability-high was identified in 2/15 patients (13%) with UCAN. Mutational signature 3, which is associated with homologous recombination deficiency, was detected in 14/15 patients (93%) with UCAN, and enriched in UCAN compared with sporadic CRC (P=0.030). In conclusion, gene panel testing can detect important genetic alterations that can be useful for diagnosis and treatment in UCAN, and may provide clinicians with important information for tailored treatment strategies.

Gastric metastasis from small bowel adenocarcinoma in a Lynch syndrome patient.

Gastric cancer is a Lynch syndrome (LS)-associated tumor, with the cumulative lifetime risk in LS patients estimated to be 5.8-13%. Hence, surveillance for gastric cancer is important for LS patients, especially in those with a family history of gastric cancer or of Asian descent. We report a very rare case of a LS patient who showed gastric metastasis from jejunal adenocarcinoma curatively resected 8 years prior. A 79-year-old female was diagnosed with a synchronous gastric submucosal tumor (SMT) and right-sided colon cancer. She was referred to our hospital as she and her family had histories of LS-associated tumors. She underwent curative intent surgery for the tumors. Postoperative histopathological examination revealed the gastric SMT was an adenocarcinoma completely covered by non-neoplastic gastric mucosa. Immunohistochemical analyses showed the gastric SMT had the same expression pattern for CDX2, cytokeratins 7 and 20 as the jejunal adenocarcinoma. Thirty-four months after surgery the patient is alive without recurrence or any other LS-associated tumors. To the best of our knowledge, this is the first report of gastric metastasis from small bowel adenocarcinoma in a LS patient. Awareness of this case may be important for gastric cancer surveillance in LS patients.

Efficacy of BRAF inhibitor and anti-EGFR antibody in colorectal neuroendocrine carcinoma.

Neuroendocrine neoplasms of the colon and rectum are colorectal epithelial neoplasms with neuroendocrine differentiation. A platinum regimen used for small cell lung cancer is the currently recommended chemotherapy for gastroenteropancreatic neuroendocrine carcinomas (GEP-NECs), regardless of the organ. The BRAF V600E mutation has been recently reported as a druggable driver mutation in colorectal NECs. In BRAF V600E mutant colorectal cancer, a combination of BRAF inhibitor and anti-epidermal growth factor receptor (EGFR) antibody, with or without a MEK inhibitor, is recommended. Here, we report the case of 77-year-old man who had lymph node recurrence after surgery for primary ascending colonic NEC. Two cytotoxic regimens, cisplatin plus irinotecan and modified FOLFOX6, were administered as first- and second-line chemotherapies with no remarkable response observed. At this point, genetic analysis confirmed the tumor harbored a BRAF V600E mutation. Thus, a regimen of BRAF inhibitor plus anti-EGFR antibody was administered. After commencing this regimen, carcinoembryonic antigen levels decreased within normal range, and there was dramatic shrinkage of the lymph node metastases observed by chest and abdominal computed tomography scans. To our knowledge, this is the first reported case of a colorectal NEC responding to a BRAF inhibitor and anti-EGFR antibody.

Advanced Stage Is a Risk for Severe Neutropenia in Breast Cancer Patients Undergoing Neoadjuvant Adriamycin/Cyclophosphamide/Docetaxel Chemotherapy.

Background: Severe neutropenia, including febrile neutropenia, is a major toxicity of systemic chemotherapy that leads to delays in treatment, higher costs, and mortality. Severe neutropenia may occur during neoadjuvant chemotherapy even when the patients are free from known risk factors. Pegfilgrastim, a covalent conjugant of filgrastim that stimulate the production of neutrophils, is used for prevention. The current study aimed to reveal the characteristics of patients who need pegfilgrastim for primary prophylaxis to prevent severe neutropenia, including febrile neutropenia and grade 3 neutropenia, during neoadjuvant chemotherapy. Methods: A retrospective analysis of 83 patients treated with neoadjuvant adriamycin/cyclophosphamide followed by docetaxel chemotherapy was performed. The factors which associated with severe neutropenia were examined by univariate and multivariate analyses. Results: Severe neutropenia developed in one of 22 patients (5%) with pegfilgrastim for primary prophylaxis and in 17 of 61 patients (28%) without it. In 83 patients, the incidence of severe neutropenia was significantly decreased in the patients with pegfilgrastim for primary prophylaxis shown by the univariate analysis (P = 0.023) and multivariate analysis (P = 0.030). In 61 patients without pegfilgrastim for primary prophylaxis, the univariate analysis showed that severe neutropenia was associated with tumor size (P = 0.004), clinical stage (P = 0.009), and cancer antigen 15-3 (CA15-3) (P = 0.026). The multivariate analysis showed that clinical stage was associated with severe neutropenia (P = 0.021). Conclusions: The current study demonstrated that advanced stage is a risk for severe neutropenia in patients treated with neoadjuvant adriamycin/cyclophosphamide followed by docetaxel chemotherapy. Given that prophylaxis with pegfilgrastim was associated with significantly lower incidence of severe neutropenia, patient with advance stage breast cancer may benefit from pegfilgrastim during neoadjuvant chemotherapy.

[A Case of Unresectable Advanced Gastric Cancer Resected by Conversion Surgery after Trastuzumab Combination Chemotherapy].

A 74-year-old man presented to our hospital with a mass in the left supraclavicular fossa. He was diagnosed with advanced gastric cancer with liver metastasis and left supraclavicular and para-aortic lymph node metastasis, cT3N2M1 (LYM, HEP), cStage Ⅳ(the Union for International Cancer Control, TNM 7th edition). He received a total of 3 courses of S- 1 plus cisplatin therapy. Since he developed adverse reactions such as anorexia, renal dysfunction, and thrombocytopenia and the tumor was HER2-positive, he received 25 courses of capecitabine, cisplatin, and trastuzumab chemotherapy. Three years and 2 months after the first chemotherapy, remarkable tumor reduction was observed. The patient then underwent radical distal gastrectomy with D2 lymphadenectomy, and R0 resection was achieved. The histopathological diagnosis was ypT1aN0M0, ypStage ⅠA. Chemotherapy with trastuzumab may improve the long-term prognosis of HER2-positive Stage Ⅳ gastric cancer if the disease is controlled and radical resection can be achieved.

[A Case of Long-Term Survival with Multidisciplinary Treatment after Surgery for Duodenal Cancer with Left Supraclavicular Lymph Node Metastasis].

The patient was a 71-year-old man with a diagnosis of duodenal carcinoma. Abdominal computed tomography(CT) showed no distant metastasis, and he underwent subtotal stomach-preserving pancreaticoduodenectomy. Postoperative adjuvant chemotherapy was not administered. A left supraclavicular lymph node recurrence was detected on CT 15 months after surgery. Capecitabine and oxaliplatin(CAPOX)therapy was administered and the metastatic lesion shrank. Positron emission tomography(PET)-CT showed no lesions at other sites and left cervical lymph node dissection was performed 5 months after the recurrence. Postoperative adjuvant therapy with S-1 was administered for 6 months. However, 2 years and 10 months after the first recurrence, CT showed recurrence in the left supraclavicular lymph node. CAPOX therapy was resumed, but due to an allergic reaction to oxaliplatin, the patient was treated with capecitabine alone. The recurrent lesion was gradually increased in size, and FOLFIRI therapy was introduced. One year and 5 months after secondary recurrence, PET-CT showed that the second recurrent lesion had grown but was confined to the left supraclavicular lymph node, so radiation therapy(60 Gy)to the left neck was performed. The disease was stable for about 10 months and chemotherapy could be discontinued. The lesion increased in size thereafter, and the patient died 7 years after initial surgery.

[A Case of Granulocyte Colony-Stimulating Factor-Associated Aortitis during Neoadjuvant Chemotherapy for Esophageal Cancer].

A 71-year-old man with middle thoracic esophageal cancer was treated with neoadjuvant chemotherapy using docetaxel plus 5-FU plus cisplatin therapy and was also administered pegfilgrastim. Blood tests showed elevated white blood cell counts and C-reactive protein levels before the start of the third course. Contrast-enhanced computed tomography revealed wall thickening of the aortic arch. We diagnosed this as aortitis due to pegfilgrastim. Inflammation was improved with conservative treatment. We then performed video-assisted thoracoscopic esophagectomy. Drug-induced vasculitis should be included in the differential diagnosis of patients with elevated inflammation markers of unknown cause following the administration of granulocyte colony-stimulating factor preparations.

[Laparoscopic Abdominoperineal Resection for Anal Canal Cancer with Pagetoid Spread].

A woman in her 60s had been aware of perianal erosions for 1 month. Skin biopsy showed Paget's cells in the stratified squamous epithelium, and immunohistochemistry showed negative staining for CK7 and positive staining for CK20. Colonoscopy revealed well-differentiated adenocarcinoma in the anal canal. Computed tomography showed neither regional lymph node metastasis nor distant metastasis. Hence, she was diagnosed with anal canal carcinoma with pagetoid spread. We determined the extent of resection of the skin lesion preoperatively by mapping biopsy, and performed laparoscopic abdominoperineal resection. The pathological findings revealed adenocarcinoma(tub1, tub2), and the skin resection margin was negative. Immunohistochemistry for Paget's cells in the stratified squamous epithelium showed negative staining for GCDFP-15 and CK7, and positive staining for CK20. Twenty-four months after surgery, we detected right inguinal lymph node metastasis and performed right inguinal lymphadenectomy. As of 4 months after the lymphadenectomy, no local recurrence or distant metastasis has been detected during follow-up examinations.

[Laparoscopic Abdominoperineal Resection after Preoperative Chemoradiotherapy for Adenocarcinoma Associated with Anal Fistula].

A 72-year-old man had a chief complaint of anal pain and difficulty in defecation. He was diagnosed with adenocarcinoma by biopsy from a tumor of the anal canal. A computed tomography scan revealed neither regional lymph node metastasis nor distant metastasis. Hence, he was diagnosed with cT3N0M0, cStage Ⅱa anal canal cancer. Preoperative capecitabine- based chemoradiotherapy(CRT)(50.4 Gy in 28 fractions of 1.8 Gy each)was implemented. Digital rectal examination and imaging evaluation 8 weeks after preoperative CRT revealed that the tumor had shrunk. Fifteen weeks after preoperative CRT, laparoscopic abdominoperineal resection was performed. The pathological findings showed mucinous adenocarcinoma associated with anal fistula. At present, 12 months after the operation, no local recurrence and distant metastasis has been detected under follow-up evaluations.

NQO1 as a Marker of Chemosensitivity and Prognosis for Colorectal Liver Metastasis.

BACKGROUND/AIM: This study aimed to evaluate how NAD(P)H: quinone oxidoreductase-1 (NQO1) affects survival after hepatectomy in patients with colorectal liver metastasis (CRLM). PATIENTS AND METHODS: A retrospective analysis was conducted of 88 consecutive patients who underwent hepatectomy for CRLM. Of the 88 patients, preoperative chemotherapy was administered to 30 patients. Immunohistochemistry of the resected specimens was conducted using monoclonal anti-NQO1 antibody. RESULTS: NQO1-positive expression in tumor cells of CRLM was associated with worse overall survival (p=0.026) and was an independent adverse prognostic factor in multivariate analysis (hazard ratio=5.296, p=0.007). Among 30 patients who received preoperative chemotherapy, patients with loss of NQO1 expression in non-neoplastic epithelial cells of the bile ducts (NQO1 polymorphism: n=19) showed significantly better response to preoperative chemotherapy for CRLM (p=0.004). CONCLUSION: NQO1-positive expression in tumor cells of CRLM may be an adverse prognostic factor after hepatectomy for CRLM.