[Implantation metastasis of colorectal adenocarcinoma in an anal fistula]

In our case report, we describe a rare form of metastatic colorectal carcinoma, in which tumor cells spread intraluminally and metastasis occurs with implantation mechanism far from the primary tumor. A 43-year-old male patient developed perianal abscess. After surgical intervention a fistula-in-ano appeared at the site of the abscess. Fistulotomy was performed in another hospital. A few months later, we admitted him to our department with an abnormal tissue proliferation appearing in the surgical area. Histology confirmed adenocarcinoma. Colonoscopy detected tissue proliferation in the sigmoid colon, causing a subtotal stenosis. Laparoscopic rectosigmoid resection and per anum tumor excision were performed. Detailed histological examination confirmed the same mucinous adenocarcinoma in the colon and the anorectal malformation. In this case, implantation mechanism is likely in the development of a synchronous tumor at the site of the fistula-in-ano. Implantation metastasis is considered rare, only a few cases have been reported in the international literature so far. We are not aware of any similar case reported from Hungary. Orv Hetil. 2023; 164(3): 110-113.

Subcutaneous metastasis after three surgeries for brain metastasis from lung cancer: A case report and review of the literature

Lung cancer is a common malignancy that is frequently associated with distant subcutaneous metastasis. However, reports of subcutaneous metastasis of lung cancer after three surgeries for recurrent brain metastasis are scarce. The present study describes the case of a 49-year-old female patient who was admitted to our hospital with a cutaneous mass. The patient had a history of lung cancer and had undergone three surgeries for brain metastases. The subcutaneous mass was considered to be an implantation metastasis from the previous brain metastases. The cutaneous mass was grossly resected and histopathological examination revealed adenocarcinoma. This case highlights the need to perform a comprehensive analysis for suspected subcutaneous masses in lung cancer patients. Furthermore, pathological examination is crucial for accurate diagnosis and timely treatment.

Gastric wall implantation metastasis of retroperitoneal extraskeletal osteosarcoma: A case report and review of the literature

Retroperitoneal extraskeletal osteosarcoma (ESOS) is a rare and highly invasive tumor that is usually diagnosed at an advanced stage due to the insidious onset. The present study analyses a case of retroperitoneal ESOS and its clinical, radiological and therapeutic conditions, and also provides a review of the literature. A 52-year-old male was diagnosed with retroperitoneal ESOS. The patient succumbed to the condition one year after the initial surgery. During treatment, the patient underwent two additional surgeries and two courses of chemotherapy. In the present case, a peritoneal metastatic lesion of ESOS was shed from the peritoneum and implanted into the outer membrane of the stomach and metastasis was identified, this has rarely been reported in the literature. Retroperitoneal ESOS should be considered in the differential diagnosis of a retroperitoneal mass in order to facilitate the management of surgery and help determine the appropriate treatment of the disease.

Implantation metastasis from adenocarcinoma of the sigmoid colon into a perianal fistula: a case report

Implantation metastasis from a colorectal cancer into a perianal fistula is very rare. Such lesions are commonly mistaken as benign perianal abscesses or fistulas and diagnosed only after pathological analysis of surgically excised fistulas. Once diagnosed, the management of this condition remains controversial. We report a case of perianal fistula that was unexpectedly found to harbor adenocarcinoma on biopsy. Further investigation by colonoscopy and computed tomography scan revealed a sigmoid adenocarcinoma. Abdominoperineal resection was performed. Histology and immunohistochemical staining was identical in both primary and metastatic tumors. We herein review the literature on the metastasis of colorectal cancer to a benign perianal fistula presumably acquired through implantation of viable malignant cells shed from the primary tumor and discuss the approach to this rare scenario in colorectal cancer surgery.