Rectal metastasis in Lung cancer: A case report and review of the literature

Gastrointestinal metastasis in lung cancer is not commonly encountered clinically, of which rectal involvement is a sporadic event. There were few reports about rectal metastasis in lung cancer. All of them had a dismal prognosis. We report a case of synchronous rectal metastasis in a lung cancer patient with a different clinical scenario, treatment, and prognosis. The patient presented with infrequent hematochezia due to a rectal mass confirmed as adenocarcinoma on core biopsy. Computer tomography showed many nodules in both lungs, which raised the initial diagnosis of pulmonary metastasis in rectal cancer. However, we decided to perform immunohistochemistry on the rectal biopsy specimen, which, surprisingly, revealed the site of origin was from the lung. Subsequently, next gene sequencing was performed and detected an exon 19 deletion on the EGFR gene. Though he had infrequent hematochezia, we decided to treat him with Erlotinib (a first-generation TKI) and closely monitored the rectal symptoms. Six months later, he achieved a complete response of both lung and rectal lesions. At present, he has been progression-free for 14 months. Thus, physicians should always be aware of this differential diagnosis in synchronous tumors and carefully consider the optimal treatment to start.

Lobular Mammary Carcinoma Presenting as an Obstructing Rectal Mass

Breast cancer is the leading cause of cancer death in women, and while metastasis is common to areas like the bone, lungs, and brain, it is rare to metastasize to the gastrointestinal tract and especially to the rectum. Due to the rarity of this condition and its resemblance clinically and radiologically to primary gastrointestinal tract tumors, diagnosis and treatment are challenging. We present a case of metastatic lobular mammary carcinoma in a 52-year-old Bahraini woman who presented with an obstructing rectal mass.

Large Bowel Obstruction Caused by Metastatic Prostate Cancer: A Case Report

Bowel obstruction is a frequently encountered condition worldwide that causes numerous admissions to hospitals. Metastatic carcinoma has been identified as one of the infrequently encountered causes of bowel obstruction. Prostate cancer typically metastasizes to lymph nodes, bone, lungs, liver, and brain. In this article, we reported the case of a 75-year-old man who presented with bowel obstruction due to narrowing and stricture of the rectum. Primary rectal mass was initially diagnosed, but upon further investigation, it was found that the mass resembled prostate tissue. The bowel obstruction was managed surgically with a colostomy. The patient was later referred to oncology for chemotherapy and hormonal therapy.

EP.TU.296A Significant Difference in Cancer Proportions Between Two Modelled Cohorts Investigated by 2-WeekWait (2WW) Colorectal referral pathway

Aim To compare the proportions of malignancy between two modelled cohorts of referred and investigated by our colorectal 2 WW referrals pathway. Methods Two modelled cohorts were analysed from our prospectively maintained colorectal 2WW referrals database from August 2018 to July 2019. One cohort (group A) included patients without anemia, rectal mass or overt rectal bleeding. The other (group B) included the rest of referrals. Data collected and analysed in each group included total numbers of referrals, investigated referrals and malignancy proportion in each group. One tailed Z test was used to analysis statistical difference. Results 4240 referrals were made to our colorectal 2 WW pathway during the given period. 1333 (31%) were group A and 2907 (69%) were group B. Total number of patients investigated in group A was 1227, of those only 34 (2.8%) were colorectal cancer and 18 (1.5%) were extracolonic cancer. One the other hand, 2705 patients were investigated in group B, colorectal malignancy were found in 142 (5.3%) patients and 33 (1.2%) were extracolonic. There was a significant difference (p < 0.05) in total number of malignancies between Group A (53/4.3%) and Group B (175/6.5%). Conclusion While the 2 Week-Wait referral pathway plays an important role in rapid testing and identifying colorectal cancer, there was a difference between malignancy distribution within the referrals. this difference doesn’t reflect a clinical significance but it can be a good stratification tool.

TTF-1 Immunoexpression in Primary Rectal Adenocarcinoma with Brain Metastasis

Introduction/Objective Rectal adenocarcinoma metastatic to the brain occurs in 0.6%-3% of cases and is associated with advanced-stage disease.TTF-1 expression in rectal adenocarcinoma is an uncommon finding and less than five cases of TTF-1 positive rectal adenocarcinomas have been reported in the literature. Herein, we report a primary rectal adenocarcinoma with biopsy-proven brain metastasis, radiographic evidence of hepatic and pulmonary involvement and unique expression of TTF-1, a marker with high sensitivity for primary pulmonary and thyroid lesions. Furthermore, we discuss the importance of distinguishing this entity from Pulmonary Enteric Adenocarcinoma (PEA). Methods/Case Report A 68-year-old male with hypertension presented with a two-day history of left facial drooping and dysarthria. Brain MRI revealed a 2.9 cm, contrast-enhancing, solitary, right insular mass. A pterional craniotomy and gross total resection of the lesion was performed. Microscopic examination revealed metastatic adenocarcinoma with immunohistochemical expression of CAM 5.2, CDX2, CK20, focal immunoreactivity with Napsin A and TTF-1, and lack of expression of CK7 and Synaptophysin. Radiographic investigation revealed a right posterior rectal lesion and multiple hepatic and bilateral pulmonary nodules. Sigmoidoscopy a fungating, partially circumferential, ulcerated, and friable rectal mass extending 6 cm proximally from the anal verge. Biopsy demonstrated invasive well- differentiated rectal adenocarcinoma with microsatellite stable phenotype, expression of CDX2, CD20, TTF-1 in the lesional cells, and lack of immunostaining with CK7. Given these findings, we favored a diagnosis of invasive well- differentiated rectal adenocarcinoma. Results (if a Case Study enter NA) N/A Conclusion TTF-1 positive rectal adenocarcinoma is an important differential diagnosis for PEA. As the two primary lesions share histomorphological features, clinical history, radiological findings and immunohistochemical staining with CK7 can aid in distinguishing between the two entities. Recent literature suggests a possible role for CDH17 and SATB2 immunostaining to increase the sensitivity and specificity of distinction between the two entities. Lack of expression of CK7 in both the rectal and brain lesion biopsies, radiological finding of numerous bilateral pulmonary infiltrates and one large, solitary rectal mass supports the diagnosis of advanced stage primary rectal adenocarcinoma with distal metastasis in our patient.

SP1.1.13Assessing quantitative FIT within the colorectal two-week wait pathway as a triage tool to focus endoscopy services

Aims Quantitative Faecal Immunochemical test (qFIT) is highly specific for luminal colonic pathology. This study models the potential impact on health care services of its introduction as a tool of triage for the 2-week wait referrals pathway. The Model utilises the recently published NICEFIT tudy. Methods All symptoms and results for patients within the colorectal two-week wait pathway are prospectively collated into a relational database. We modelled the impact of introducing targeted FIT testing to those patients without anaemia, rectal mass or overt rectal bleeding. Based on the recent NICEFIT Study, we set a population positivity value of 37% at 2µg/g with sensitivity of identifying colorectal cancer of 97%. Results 4240 patients were referred in 12 months up to till July 2019. 1333 referrals met the modelled criteria. These 1333 patient events generated 1619 investigations in 1227 patients. Malignancy was found in 4.3% of the investigated referrals (2.8% colorectal, 1.5% extracolonic). By applying FIT to the selected demographics with a positive value of 37%, the number of colonoscopies would fall by 63% (from 815 to 303) with estimated cost saving of £192,000. The FIT negative group would be investigated by selective cross-sectional imaging, with selected use of endoscopy as needed. Conclusion The high sensitivity of FIT permits its application as a screening tool in selected symptomatic patients. This can reduce the number of colonoscopies performed by almost 63% within a defined patient group. This would reduce the waiting time for positive high-risk patients as well as cutting overall costs.

Abdominotransanal resection of a strangulated rectal carcinosarcoma

This is a case of a 75-year-old man who presented with a 7-month history of a reducible rectal mass. The patient came to the emergency department with a prolapsed necrotic bowel involving a strangulated segment with the rectal mass. He underwent an abdominotransanal resection through a combined abdominal and perineal approach. His postoperative course was unremarkable. Histopathological and immunohistochemical studies showed a rectal carcinosarcoma. Because of a state-mandated lockdown due to the COVID-19 pandemic, the patient failed to follow-up. He was later seen to have metastatic progression. Owing to the poor functional status of the patient, the shared decision of the multidisciplinary team, the patient and his family was to manage him with palliative intent.