Audit of Lymph Node Sampling in Colorectal Carcinoma Resections-implication for Prognosis and Management

Aims: To review lymph node yield in colorectal carcinoma (CRC) resections and its associated factors in a Nigerian Teaching Hospital practice. Study design: This was a retrospective cross-sectional study. Place and duration of study: Department of Pathology, University College Hospital Ibadan Nigeria and colectomies from January 2014 to December 2018 were reviewed. Methodology: Surgical Pathology reports of CRC resections at the University College Hospital Ibadan over 5 years (2014-2018) were reviewed. Colectomy lengths, tumour location (colon/rectum), tumour size, comment on presence of lymph node (yes/no), lymph node count, presence of attached mesentery (yes/no), histological subtype, tumour grade, presence of tumour-positive node and count, and pT stage were documented. Fisher’s Exact test was employed to test the effects of these variables on presence of lymph node and tumour-positive node at histology using SPSS 20. Significance level was set at P < .05. Results: Of 66 histology reports retrieved, 62 (93.9%) had comments on search for lymph nodes and attached mesentery was documented in 25 (37.9%). The median colectomy length and tumour size were 25cm (6cm-152cm) and 6.75cm (3-30cm) respectively. Lymph nodes were present in 52 (78.8%) specimens; 28 (53.8%) of these had tumour-positive lymph nodes. Adenocarcinoma NOS was the commonest histological subtype 53 (80.3%), mucinous carcinoma 12 (18.2%) and signet ring carcinoma 1 (1.5%). Eighteen, 9 and 1of adenocarcinoma NOS, mucinous carcinoma, and signet ring carcinoma respectively had tumour-positive lymph nodes. Finding of lymph node was significantly associated with comment on search for lymph node (p < .01) while finding tumour-positive nodes was associated with histological subtype, presence of mesentery, late tumour stage and lymph node count ≥ 12 (p < .05). Conclusion: If lymph nodes were present, more than likely there will be metastatic involvement. To increase Lymph node yield in CRC resections, submission of mesentery and search for lymph nodes is indicated. When nodes are absent, a mention is required for practice audit. It is imperative to include both clinical and grossing notes for lymph nodes to certify and guide precise staging of the cancer.

Primary signet ring carcinoma of the rectum: a rare entity

Signet ring cell carcinoma constitute an uncommon histological type of rectal cancer with less than 1% of all rectal neoplasms. It usually behaves aggressively and has an inferior prognosis. Herein, we present a rare case in young male diagnosed by trucut biopsy.

Gastric Metastasis from Colorectal Cancer Mimicking a Submucosal Tumor

Signet-ring cell carcinoma, a colorectal cancer (CRC) subtype, sometimes shows metastases to uncommon metastatic sites. However, gastric metastasis is extremely rare. Here, we describe a case of gastric metastasis from colonic cancer. A 76-year-old woman presented with anemia. Colonoscopic biopsy revealed a CRC on the transverse colon showing a poorly differentiated adenocarcinoma with a partial component of the signet-ring carcinoma. Computed tomography revealed multiple subcutaneous nodules on her chest and back, and a tumor in the left lower lobe of her lung. Esophagogastroduodenoscopy showed a submucosal tumor-like lesion in the upper gastric body, and endoscopic biopsy revealed the poorly differentiated adenocarcinoma along with the partial component of the signet-ring carcinoma as well as the colonic, subcutaneous, and pulmonary lesion. The findings of endoscopic and microscopic examinations revealed gastric metastasis from CRC on the transverse colon. A systemic chemotherapy was given, and the biopsy conducted 1 year after the initial chemotherapy revealed no evidence of the residual tumor tissue in the gastric lesion. However, best supportive care was recommended depending on metastasis to the rectum. Our case suggests that gastric metastases from CRC should be considered in patients with lesions resembling a submucosal tumor accompanied by central depression and erosion.

Predictive Factors of Positive Circumferential and Longitudinal Margins in Early T3 Colorectal Cancer Resection

Background. Malignant involvement of circumferential resection margin (CRM) and longitudinal resection margin (LRM) after surgical resection of colorectal cancer (CRC) are associated with higher rates of recurrence and development of distant metastasis. This can influence the overall patient’s prognosis. The aim of the current study was to identify pathological factors as predictors for the involvement of resection margins in early T3 CRC. Patients and Methods. Fifty patients radiologically diagnosed to have cT3a/b (CRC) were included in the study. After resection, the pathological examination was performed to identify patients with positive CRM and/or LRM. Relations between the different pathological parameters and the CMR and LRM involvements were assessed. Results. Positive CRM was present in 17 cases (34%), while positive LRM was found in 6 cases (12%). The involvement of both margins was significantly associated with rectal tumors and tumors with infiltrative gross appearance, grade III, deeper invasion, and positive lymph node metastases. Also, there was a significant association between both margins’ positivity and other pathological parameters as signet ring carcinoma, tumor budding, perineural and vascular invasion, high microvessel density (MVD), and sinusoidal vascular pattern, while the presence of necrosis and infiltrative advancing tumor front was significantly associated with CRM involvement only. The depth of tumor invasion and signet ring carcinoma were identified as independent predictor factors for positive CRM and LRM, respectively. Conclusion. Preoperative identification of these pathological parameters can be a guide to tailor the management plan accordingly.