Five-Fraction Radiosurgery Using a Biologically Equivalent Dose of a Single Fraction of 24 Gy for a 3-cm Parasagittal Para-Central Sulcus Brain Metastasis From Adenocarcinoma of the Cecum

An isolated single brain metastasis (BM) is an extremely rare manifestation of failure in patients with cecal adenocarcinoma (CAC). Total en bloc resection (while preserving function) of a 3-cm BM involving both the primary motor and sensory cortexes presents a conundrum: achieving long-term local control and safety of such a BM is also challenging for stereotactic radiosurgery (SRS). We describe the case of a 3.1-cm BM from CAC in the left parasagittal para-central sulcus region, which was treated using five-fraction SRS with a biologically effective dose (BED) of 81.6 Gy. In the SRS, the gross tumor volume (GTV, 7.14 cm3) was defined based on computed tomography (CT)/T1/T2 matching (enhancing lesion 11.66 cm3), and 98.7% of the GTV (CT/T2 mass) was covered with 43.6 Gy (58% isodose) using volumetric-modulated arcs. The maximum tumor response was partial (19.7% of the prior GTV) and sustained for 15.2 months, leaving minor neurological symptoms. However, the patient developed neurological worsening at six months, attributed to adverse radiation effects with a CT/T1/T2 mismatch, for which medical management, including the addition of bevacizumab (BEV), was effective for one year. Multi-fraction SRS with a high marginal and internal BED and sequential systemic therapy, including BEV, can be a minimally invasive, efficacious, and durable treatment option for a large CAC-BM involving the central sulcus. Early co-administration of BEV following SRS, dose escalation to the GTV boundary, and more than five fractions of SRS may be considered to improve the efficacy and safety further.

Local recurrence of submucosal invasive colorectal cancer after endoscopic submucosal dissection revealed by copy number variation

We report a case in which analysis of copy number variation revealed local recurrence of submucosal invasive colorectal cancer after curative endoscopic submucosal dissection (ESD). An 86-year-old man with a history of abdominoperineal resection of the rectum for rectal cancer underwent resection with ESD for early-stage sigmoid cancer 5 cm away from the stoma opening. At the same time, ileocecal resection was performed for advanced cecal cancer. Twelve months after ESD, advanced cancer occurred in the area of the ESD lesion. It was unclear if the cancer was a local recurrence after ESD, implantation of cecal cancer, or a new lesion. Copy number variation analysis performed for the three lesions revealed that the new lesion originated from residual tumor cells from ESD and was unlikely to be cecal cancer.

Diagnosis of a cecal tumour with virtual colonoscopy

The authors presented a 75-year-old female patient at high risk, suspected of a cecal cancer (CC) due to discomfort in the inguinal fossa, microcytic anemia (although she was postmenopausal), liquid stools and a positive faecal occult blood test. A standard examination of the large intestine was undertaken. Conventional colonoscopy was not completed and the results of barium enema were questionable. Therefore, virtual colonoscopy (VC) was performed, which helped to localize an accurate operation site. As a result, the patient underwent right hemicolectomy. Postoperative histopathological assessment confirmed an advanced cecal cancer. Traditionally, double-contrast barium enema is used to evaluate the colon in patients after incomplete colonoscopy. However, the accuracy of this test is lower in comparison to endoscopy or VC. An incomplete colonoscopy examination may occur in up to 10% of patients. Tortuous course of the colon, diverticulosis, strictures, obstructing mass and fixation of colonic loops due to adhesions after surgery are the most common causes of incomplete examinations. To sum up, VC can be an alternative method of evaluation of the large bowel in patients after an incomplete colonoscopy examination, as follows from the presented case and the available literature.