Spontaneous Regression Of Advanced Transverse Colon Cancer With Remaining Lymph Node Metastasis
Nishiura, B., Kumamoto, K., Akamoto, S., Asano, E., Ando, Y., Suto, H., Kishino, T., Oshima, M., Fujiwara, M., Usuki, H., Okano, K., & Suzuki, Y. (2020). Spontaneous regression of advanced transverse colon cancer with remaining lymph node metastasis. Surgical case reports, 6(1), 100. https://doi.org/10.1186/s40792-020-00858-1
View Original Source →Abstract
BACKGROUND: The observation of spontaneous regression (SR) has been well documented for many cancer types, including renal cell carcinoma, non-Hodgkin's lymphoma, leukemia, neuroblastoma, and malignant melanoma. However, the SR frequency in colorectal cancer is very rare. Therefore, the accumulation of SR colorectal cancer cases might contribute to find the regression mechanism. CASE PRESENTATION: A 67-year-old woman received colonoscopy due to being positive for fecal occult blood testing and was diagnosed as having a transverse colon cancer at a local hospital. She was admitted to our institution for surgical treatment of the colon cancer. The colonoscopy revealed a type 2 tumor of 13 mm in diameter at the hepatic flexure of the transverse colon. The enhanced computed tomography (CT) showed an enlarged lymph node in the intermediate lymph node region. The 18F-fluorodeoxyglucose positron emission tomography/CT showed no abnormal accumulation on the transverse colon; however, an abnormal accumulation was found at the enlarged lymph node. The patient was preoperatively diagnosed as having advanced transverse colon cancer with lymph node metastasis and underwent laparoscopic right hemicolectomy with D3 lymph node dissection. Pathological examination showed only a scar-like tissue and no cancerous lesion in the transverse colon, while a metastatic lymph node was histologically confirmed in the intermediate lymph node region. Loss of MLH1 and PMS2 expression was observed in the cancer cells of both biopsy specimens and resected lymph nodes. No recurrence was seen for 5 years after surgery. CONCLUSIONS: We reported a rare case of SR of the primary transverse colon cancer without regression of the metastatic regional lymph node. We considered that colorectal cancer with SR should be resected because even if SR of the primary lesion occurs, lymph node metastasis might have an inconsistent behavior as shown in the present case.
Case Details
Disease Location
Colon
Personal Characteristics
67-year-old woman. Past medical history of appendicitis and mild pneumonitis.
Clinical Characteristics
Colonoscopy was preoperatively performed for the marking neat of the tumor using an ink injection method. The tumor revealed a type 2 lesion of 13 mm in diameter at the hepatic flexure of the transverse colon. The histological diagnosis of the biopsy was a poorly differentiated carcinoma with a signet-ring cell carcinoma component. Barium enema of the colon revealed a trapezoid-shaped lesion at the same location of the transverse colon. PET/CT showed an abnormal accumulation on the intermediate lymph node. She was diagnosed with an advanced transverse colon cancer with lymph node metastasis. Laparoscopic right hemicolectomy with d3 lymph node dissection was performed 3 months later after the initial colonoscopy
Remission Characteristics
Macroscopically, the tumor was not observed in the resected specimens. A scar-like lesion around the preoperative inking was seen in the colonic mucosa. Pathological findings revealed inflammatory cell infiltration and fibrosis between the submucosa (sm) and the muscularis propria (mp)
Treatment & Mechanisms
Proposed Remission Mechanisms
Antitumor immune response might be the most likely explanation
Clinical Treatment
Biopsy