"Oncologic Results and Risk Factors for Recurrence in Patients With Locally Advanced Rectal Cancer and Pathologic Complete Response After Neoadjuvant Treatment. Results From an Observational Retrospective Multicenter Long-term Follow-up Study".

Oncologic Results and Risk Factors for Recurrence in Patients With Locally Advanced Rectal Cancer and pCR After Neoadjuvant Treatment.

Pathologic complete response (pCR) after multimodal treatment for locally advanced rectal cancer (LARC) patients is considered as the gold-standard of treatment success as it is associated to privileged oncologic outcome. Nevertheless, data from multicenter high-volume cohorts with long term follow-up are scarce.

This is a multicenter observational study using prospectively collected data from the Spanish Rectal Cancer Project database.

The main objective of the study is to update long-term oncologic follow-up of those patients treated for LARC with nCRT and surgery (either TME or subtotal TME; S-TME) who had obtained a pCR.

Secondary objective is to analyze demographic, clinical, operative and treatment variables in search of related factors to adverse oncologic outcomes, like distant recurrence or tumor-related deaths.

The results are reported in accordance with the STROBE (STrengthening the Reporting of OBservational studies in Epidemiology) Statement for observational studies.

All calculations are performed using Stata 13.1 (StataCorp, Texas, USA).

Inclusion Criteria:

• Patients with pathological confirmation of rectal cancer preoperatively, in any of its histological variants.
• Tumor located less than 12 cm from the anal margin.
• Radiological stage II or III (cT3-4 N0 and/or any T with positive cN).
• Neoadjuvant treatment with radio-chemotherapy.
• Radical surgery performed on a scheduled basis and with curative intent.
• Definitive pathology study with complete tumor regression.

Exclusion Criteria:

• Patients operated on with palliative intent.
• Patients diagnosed with a hereditary colorectal cancer syndrome.
• Patients who presented synchronous metastases at the time of diagnosis, or concurrent malignancy of another origin.
• Patients who underwent emergency surgery.