Interactions of occult tumor spread and surgical technique on overall and disease-free survival in patients operated for stage I and II right-sided colon cancer

Abstract

Purpose To determine if “medial to lateral” (ML) dissection with devascularization first is superior to “lateral to medial” (LM) dissection regarding numbers of lymph node micro metastases (MM) and isolated tumor cells (ITC) as well as 5-year disease-free (5YDFS) and 5-year overall survival (5YOS) in stage I/II right-sided colon cancer. Methods Two datasets are used. ML group consists of consecutive stage I/II patients from a prospective trial. LM group is the original dataset from a previous publication. All harvested lymph nodes are examined with monoclonal antibody CAM 5.2 (immunohistochemically). Lymph node harvest and 5YOS/5YDFS were compared between ML/LM groups, stage I/II tumors and MM/ITC presence/absence. Results 117 patients included ML:51, LM:66. MM/ITC positive in ML 37.3% (19/51), LM 31.8% (21/66) p = 0.54. The 5YDFS for patients in ML 70.6% and LM 69.7%, p = 0.99, 5YOS: 74.5% ML and 71.2% LM (p = 0.73). No difference in 5YDFS/5YOS between groups for Stage I/II tumors; however, LM group had an excess of early tumors (16) when compared to ML group, while lymph node harvest was significantly higher in ML group (p < 0.01) 15.1 vs 26.7. 5YDFS and 5YOS stratified by MM/ITC presence/absence was 67.5%/71.4%, p = 0.63, and 75.0%/71.4%, p = 0.72, respectively. Death due to recurrence in MM/ITC positive was significantly higher than MM/ITC negative (p = 0.012). Conclusion Surgical technique does not influence numbers of MM/ITC or 5YDFS/5YOS. Presence of MM/ITC does not affect 5YOS/5YDFS but can be a potential prognostic factor for death due to recurrence. Clinical trial Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic Multi-Detector Computed Tomography (MDCT) Angiography” registered at http://clinicaltrials.gov/ct2/show/NCT01351714 .

Comparing 5-Year Survival Rates Before and After Re-stratification of Stage I–III Right-Sided Colon Cancer Patients by Establishing the Presence/Absence of Occult Tumor Cells and Lymph Node Metastases in the Different Levels of Surgical Dissection

“…After routine staining and microscopic evaluation, the lymph nodes in the D1/D2 and D3 volumes were investigated by sectioning into 3-4 µm thin slides before being stained immunohistochemically by using cytokeratin CAM 5.2 antibodies, as stated in a previously published article. 11 All lymph node sections that were stained immunohistochemically were examined by the same pathologist at the hospital where the patients were included. Both clusters of malignant cells and individual tumor cells were categorized according to the tumor node metastasis (TNM) staging system of the American Joint Committee on Cancer (AJCC): 1,2 ordinary metastasis: cluster of tumor cells larger than 2 mm in diameter; micrometastasis (MM): malignant cell cluster between 0.2 and 2 mm in diameter; and ITC: tiny cell groups less than 0.2 mm in diameter or single isolated tumor cells (up to 200 cells).…”

“…10 Liquid biopsy/CTC can be useful in postoperative follow-up. 8 On the other hand, OTC defines the location of the disease, as well as the extent of it, 11 and has the potential to influence treatment. One-stepped nucleic acid amplification (OSNA) and RT-PCR can be used for upstaging the disease in stage II in up to 25-60% of patients.…”