Takashi Ogimi

Relations of Changes in Serum Carcinoembryonic Antigen Levels before and after Neoadjuvant Chemoradiotherapy and after Surgery to Histologic Response and Outcomes in Patients with Locally Advanced Rectal Cancer

Objectives: The histologic response to neoadjuvant chemoradiotherapy (nCRT) has been intimately related to outcomes in locally advanced rectal cancer. Serum carcinoembryonic antigen (CEA) levels change after nCRT and after surgery as compared with before nCRT. Methods: The subjects were 149 patients with locally advanced rectal cancer who received nCRT between 2005 and 2013. The patients were divided into 4 groups according to the serum CEA levels: group 1, 55 patients with negative serum CEA levels before nCRT; group 2, 41 patients with positive serum CEA levels before nCRT that became negative after nCRT; group 3, 37 patients with positive serum CEA levels after nCRT that became negative after surgery; and group 4, 16 patients with positive serum CEA levels after nCRT as well as after surgery. Results: Pathological complete response, T downstaging, and tumor shrinkage were significantly higher in group 1 than in other groups. Disease-free survival was significantly poorer in group 4. The lack of a decrease in the serum CEA level in group 4 was most likely attributed to the persistence of micrometastases outside the resection field. Conclusions: Changes in serum CEA levels measured before nCRT, after nCRT, and after surgery can be used to reliably predict the histologic response to nCRT and outcomes.

The Number of Natural Killer Cells in the Largest Diameter Lymph Nodes Is Associated with the Number of Retrieved Lymph Nodes and Lymph Node Size, and Is an Independent Prognostic Factor in Patients with Stage II Colon Cancer

Objective: We previously reported that the largest diameter of retrieved lymph nodes (LNs) correlates with the number of LNs and is a prognostic factor in stage II colon cancer. We examine whether T, B, and natural killer (NK) cells in LNs are related to the number of LNs and survival. Methods: The subjects comprised 320 patients with stage II colon cancer. An LN with the largest diameter was selected in each patient. The positive area ratios of cells that stained for CD3 and CD20, and the numbers of CD56-positive cells were measured. Results: The CD3-positive area ratio was 0.39 ± 0.08 and CD20-positive area ratio was 0.42 ± 0.10. The mean number of CD56-positive cells was 19.3 ± 22.7. The area ratios of B cells and T cells and the number of NK cells were significantly related to the sizes of the largest diameter LNs. The number of NK cells significantly correlated with the number of LNs and was an independent prognostic factor. On multivariate analysis, pathological T stage (T4 or T3; HR 4.71; p < 0.001) and the number of CD56-positive cells (high or low; HR 0.22; p < 0.001) were found to be independent prognostic factors. Conclusions: The number of NK cells in the largest diameter LNs can most likely be used as a predictor of recurrence.

Perforated gastrointestinal stromal tumor in the small intestine: A rare case of Torricelli-Bernoulli sign

The Torricelli-Bernoulli sign is a computed tomography (CT) finding that occurs when ulceration/necrosis of a submucosal gastrointestinal tumor releases a stream of air bubbles into the intestinal lumen. A 75-year-old man developed acute abdominal pain at night and presented to a local doctor. Acute abdomen was diagnosed and he was referred to the Emergency Department at Tokai University Oiso Hospital. On CT scans, disseminated intestinal tumor-like lesions were seen in the right lower abdomen. The Torricelli-Bernoulli sign and free intraabdominal gas were observed, so perforation of an intestinal tumor was diagnosed and emergency surgery was performed. At operation, there was scanty opaque ascites in the right lower abdomen and an ileal tumor associated with nodules that suggested peritoneal dissemination. Partial resection of the ileum was performed and peritoneal lavage was conducted. The patient was discharged on postoperative day 11. Histopathological examination revealed a high risk gastrointestinal stromal tumor. The abdominal nodules were metastases, indicating that the tumor was Stage IV. The patient is currently on treatment with an oral tyrosine kinase inhibitor (imatinib).

Mucinous components assessed by magnetic resonance imaging in primary rectal cancer tissue before and after chemoradiotherapy and tumor response

BackgroundMucinous rectal carcinoma has been reported to have a lower survival rate and a poorer histologic response to chemoradiotherapy(CRT). Magnetic resonance imaging (MRI) can accurately evaluate the amount of mucin pools (MP) in primary cancer tissue. We compared the degree of MP on MRI before and after CRT with the histologic findings of resected specimens to investigate the predictors of response to CRT.MethodsThe study group comprised 205 patients with rectal adenocarcinoma who received preoperative CRT. MPs were measured on MRI before and after CRT and in resected specimens. The degree of MP was classified into five classes according to the MP area ratio: 0%, class I; 1 to 19%, class II; 20 to 49%, class III; and 50% or higher, class IV.ResultsThe degree of MP on MRI was largely unchanged after CRT; however, the MP on MRI after CRT was underestimated in 26.3% of patients as compared with that in resected specimens. A pathological complete response was obtained in patients who initially had no MP or had an MP ratio of less than 20%. The tumor volume was significantly greater, and the rates of tumor shrinkage and T downstaging were significantly lower in patients who had an MP area ratio of 20% or higher before CRT than in those who had an MP area ratio of less than 20%.ConclusionsThe MP area ratio measured on MRI before treatment was closely associated with the response to CRT and is a potentially useful predictor of treatment response.

Chemoradiotherapy-induced Changes in Mucinous Components in Rectal Cancer Tissue: Evaluation on High Iron Diamine-alcian Blue and Mucin 1 Staining

Background/Aim: The standard treatment for rectal cancer is neoadjuvant chemoradiotherapy (nCRT) followed by surgery. Mucinous carcinoma responds poorly to nCRT. In some patients, mucin lakes (MLs) are induced by nCRT. Identifying whether MLs are induced or originally present would be of great importance. Patients and Methods: We studied 20 patients with MLs (CRT-MC group) among 205 patients who received nCRT. Among 88 patients who did not receive nCRT, we studied 9 patients with mucinous carcinoma (non-CRT-MC group) and 18 patients with MLs in differentiated adenocarcinoma (non-CRT-AC group). Tumors were stained with high iron diamine-Alcian blue (HID-AB) and MUC1 staining. Results: Rate of AB>HID staining of cancer cells was significantly higher in the CRT-MC group than in non-CRT-MC group (p=0.0004). Rate of MUC1 staining in MLs was significantly higher in the CRT-MC group (p=0.0254). Conclusion: nCRT can induce qualitative changes in mucinous components, however, other methods are required to distinguish induced components from originally existing components.