Primary squamous cell carcinoma of the rectum: a case report and literature review

Comprehensive CT Imaging Analysis of Primary Colorectal Squamous Cell Carcinoma: A Retrospective Study

The aim of this study was to evaluate the findings of CT scans in patients with pathologically confirmed primary colorectal squamous-cell carcinoma (SCC). The clinical presentation and CT findings in eight patients with pathologically confirmed primary colorectal squamous-cell carcinoma were retrospectively reviewed by two gastrointestinal radiologists. Hematochezia was the most common symptom (n = 5). The tumors were located in the rectum (n = 7) and sigmoid colon (n = 1). The tumors showed circumferential wall thickening (n = 4), bulky mass (n = 3), or eccentric wall thickening (n = 1). The mean maximal wall thickness of the involved segment was 29.1 mm ± 13.4 mm. The degree of tumoral enhancement observed via CT was well enhanced (n = 4) or moderately enhanced (n = 4). Necrosis within the tumor was found in five patients. The mean total number of metastatic lymph nodes was 3.1 ± 3.3, and the mean short diameter of the largest metastatic lymph node was 16.6 ± 5.7 mm. Necrosis within the metastatic node was observed in six patients. Invasions to adjacent organs were identified in five patients (62.5%). Distant metastasis was detected in only one patient. In summary, primary SCCs that arise from the colorectum commonly present as marked invasive wall thickening or a bulky mass with heterogeneous well-defined enhancement, internal necrosis, and large metastatic lymphadenopathies.

Rare presentation of esophageal squamous cell carcinoma with rectal metastasis: A case report

Esophageal cancer is usually diagnosed at an advanced stage, resulting in poor survival. The common sites of distant metastasis include lung, liver and bones. The present study reports a rare case of esophageal squamous cell carcinoma (SCC) with rectal metastasis. A 65-year-old man was diagnosed with middle thoracic esophageal SCC with multiple lymph node metastasis. The patient achieved good response after chemoradiotherapy and adjuvant chemotherapy. During following up, the computed tomography and magnetic resonance scans showed a mass in front of the rectum with intact mucosa. Biopsies were performed and histopathological findings showed SCC, consistent with metastasis from primary esophageal SCC. The patient subsequently received palliative chemoradiotherapy to the rectal tumour and survived for 5 months. To the best of our knowledge, the present case is the first report of metastatic rectal SCC from the esophagus. It is important to take a biopsy of this unexpected lesion for histological analysis, which can help to discriminate metastatic from primary cancer. The goal of treatment is palliative therapy to improve quality of life and survival for this metastatic disease.

Composite intestinal adenoma-microcarcinoid: An update and literature review

Composite intestinal adenoma-microcarcinoid (CIAM) is a rare intestinal lesion consisting of conventional adenoma and small, well differentiated carcinoid [microcarcinoid (MC)] at its base. The incidence of CIAM is 3.8% in surgically resected colorectal polyps. While its pathogenesis is unknown, studies support the role of Wnt/β-catenin pathway in the tumorigenesis of CIAM. CIAMs have been primarily reported in the colon wherein they present as polyps with well-defined margins, similar to conventional adenomatous polyps. MC is usually found in adenomatous polyps with high-risk features such as large size, villous architecture, or high grade dysplasia. Histologically, the MC component is often multifocal and spans 3.9 to 5.8 millimeters in size. MC is usually confined within the mucosa but occasional CIAM cases with MC extending to the submucosa have been reported. MC of CIAM demonstrates bland cytology and inconspicuous proliferative activity. The lesional cells are positive for synaptophysin and 60% to 100% of cases show nuclear β-catenin positivity. MC poses a diagnostic challenge with its morphologic and immunohistochemical resemblance to both benign and malignant lesions, including squamous morules/metaplasia, adenocarcinoma, squamous cell carcinoma, sporadic neuroendocrine tumor and goblet cell adenocarcinoma. CIAM is an indolent lesion with a favorable outcome. Complete removal by polypectomy is considered curative. Awareness and recognition of this rare entity will help arrive at correct diagnosis and improve patient care. Currently, CIAM is not recognized as a subtype of mixed neuroendocrine-non-neuroendocrine neoplasm by WHO.

Unusual presentation of rectal squamous cell carcinoma perforation-case report and literature review

This is an unusual case of an obstructive rectal squamous cell carcinoma (SCC), causing perforation and a pelvic abscess, requiring source control and diverting colostomy. A 50-year-old female with chronic constipation presented with worsening right buttock pain for 1 month. On exam, the patient reported right hip tenderness. A computer tomography (CT) revealed rectal wall thickening with a presacral abscess. Due to the concern of rectal perforation with abscess she was taken to the operating room for proctoscopy with biopsy, colostomy diversion and drainage of the abscess over the right buttock. Pathology reported invasive rectal SCC. Rectal SCC presents similarly to rectal adenocarcinoma but its diagnosis must include special markers for cytokeratins. The treatment approach is controversial but adequately treated offers better survival than rectal ADC. Rectal SCC is rare and treated with chemoradiation however it must also be tailored to the variable acute presentations.

Human Papillomavirus Positive Squamous Cell Carcinoma of the Rectum

Squamous cell carcinoma (SCC) is most commonly seen in the esophagus and anal canal in the gastrointestinal tract. The incidence of SCC of the rectum is infrequent with no clear etiology. There have been limited reported cases of SCC of the rectum caused by human papillomavirus (HPV). Due to the rarity of carcinoma, the management of SCC of the rectum is not standardized. We report a case of a 51-year-old female with an insignificant medical history presenting with hematochezia and weight loss and was found to have HPV-positive SCC of the rectum. This case report emphasizes the importance of work-up, usefulness of HPV testing for high-risk patients, and clinical management of SCC of the rectum.

Mixed neuroendocrine and squamous cell carcinoma of the colon: A case report and literature review

INTRODUCTION

The occurrence of Neuroendocrine Carcinoma (NEC) of the colon is <2% of all colon cancers. Squamous Cell Carcinoma (SCC) is even more unusual and has an occurrence in the colon as low as 0.1% of colon cancers. Coupled together mixed NEC-SCC, is nearly unheard of. SCC of the gastrointestinal tract is usually found in the esophagus and rectum, rarely are there squamous cells even present in the colon.

PRESENTATION OF CASE

A 62-year-old female presented with abdominal pain and a palpable mass in the left lower quadrant. CT scan revealed a poly-lobulated mass in the left abdomen attached to the left colon. A left hemicolectomy was performed. There were no distant metastases at the time of diagnosis. Microscopic examination revealed NEC mixed with SCC demonstrated by keratin pearl formation.

DISCUSSION

NEC and SCC individually are unusual in the colon but together are extraordinarily rare. Histologically, the NEC in this case demonstrated squamous cell differentiation with keratin pearl formation. The median survival in studies of patients with colonic NEC is 5-10 months due to the aggressive behavior and lymph node metastases, which were present in this case. There is insufficient literature addressing ideal adjuvant therapy after resection of mixed NEC and SCC of the colon.

CONCLUSION

We present the first case of primary colon mixed NEC and SCC which presented as abdominal pain. There is a current absence of ideal therapy recommendations in the medical literature following resection of mixed NEC and SCC of the colon.

Mixed Neuroendocrine Carcinoma and Squamous Cell Carcinoma of the Colon: Case Report and Literature Review

Neuroendocrine carcinoma (NEC) of the colon is very rare, and squamous cell carcinoma (SCC) of colon cancer is rare. We recently treated a patient with both NEC and SCC that initially presented as multiple unresectable liver and lung metastases. A 68-year-old Japanese man was referred to our hospital because of diarrhea with descending colon cancer obstruction. He underwent a left colectomy. Based on immunohistochemistry results, we diagnosed mixed NEC and SCC, the primary lesion location of which was probably the lung in the final pathologic examination. He began systemic palliative chemotherapy with CDDP and CPT-11. After 3 months of treatment, shown the progressive disease, we started CDDP and VP-16. The patient was not eligible for additional chemotherapy after 2 months.