Histologic response grading after chemoradiation in locally advanced rectal cancer: a proposal for standardized reporting

Pathological Tumor Regression Grade Classifications in Gastrointestinal Cancers: Role on Patients' Prognosis

Preoperative chemotherapy or combined radiotherapy and chemotherapy (CRT), followed by surgery, represents the standard approach for locally advanced esophageal, gastric, and rectal carcinomas. To adequately evaluate the effects of neoadjuvant CRT in the resection specimens, several histopathologic tumor regression grade (TRG) scoring systems have been introduced into clinical practice. The primary goal of these TRG systems relies on a correct prognostic stratification of patients in the attempt to help clinical decision-making and influence surgical strategies, postoperative adjuvant therapies, and surveillance intensity. However, most TRG systems suffer from poor reproducibility and low interobserver concordance rates. Many efforts have been made in the identification of alternative, robust, simple, and universally accepted TRG scoring systems, which would help in the comparison of different treatment strategies and in the standardization of multimodal therapies. The aim of this review is to analyze the most commonly used TRG systems in gastrointestinal cancers highlighting their pitfalls and usefulness, depending on the tumor type.

Pathologic Assessment of Rectal Carcinoma after Neoadjuvant Radio(chemo)therapy: Prognostic Implications

Neoadjuvant radio(chemo)therapy is increasingly used in rectal cancer and induces a number of morphologic changes that affect prognostication after curative surgery, thereby creating new challenges for surgical pathologists, particularly in evaluating morphologic changes and tumour response to preoperative treatment. Surgical pathologists play an important role in determining the many facets of rectal carcinoma patient care after neoadjuvant treatment. These range from proper handling of macroscopic specimens to accurate microscopic evaluation of pathological features associated with patients' prognosis. This review presents the well-established pathological prognostic indicators and discusses challenging features in order to provide both surgical pathologists and treating physicians with a checklist that is useful in a neoadjuvant setting.

Lymph node retrieval after preoperative chemoradiotherapy for rectal cancer

BACKGROUND

Current guidelines recommend the assessment of at least 12 lymph nodes for rectal cancer staging. Preoperative chemoradiotherapy may affect lymph node yield in this malignancy. This study investigated the impact of neoadjuvant chemoradiotherapy on the number of lymph nodes retrieved from rectal cancer patients.

METHODS

An analysis of 162 rectal cancer patients who underwent curative surgery between 2005 and 2010. Seventy-one patients with stage II or III tumors received preoperative chemoradiotherapy. Using multivariate analysis, we assessed the correlation between clinicopathologic variables and number of retrieved lymph nodes. We also evaluated the association between survival and number of lymph nodes obtained.

RESULTS

On multivariate analysis, preoperative chemoradiotherapy was the only variable to independently affect the number of lymph nodes obtained. The mean number of lymph nodes was 14.2 in patients treated with preoperative chemoradiotherapy and 19.4 in those not treated (P < 0.001). In the chemoradiotherapy group, 29.6 % of patients had fewer than 12 lymph nodes obtained compared with 9.9 % in the primary surgery group (P = 0.003). After chemoradiation, the number of retrieved lymph nodes was inversely correlated with tumor regression grade. Results showed that 5-year overall and disease-free survival were similar whether the patient had 12 or more nodes retrieved or not.

CONCLUSIONS

Preoperative chemoradiotherapy reduces the lymph node yield in rectal cancer. The number of retrieved lymph nodes is affected by degree of histopathologic response of the tumor to chemoradiation. Thus, number of lymph nodes should not be used as a surrogate for oncologic adequacy of resection after neoadjuvant chemoradiotherapy for rectal cancer.

Preoperative chemoradiotherapy for rectal cancer: a comparison between intravenous 5-fluorouracil and oral capecitabine

INTRODUCTION

Capecitabine provides an attractive alternative to intravenous (IV) 5-flourouracil (5-FU) in chemoradiation regimes for rectal cancer by avoiding the need for intravenous access and inpatient stay. We aimed to compare retrospectively the efficacy of concurrent capecitabine with IV 5-FU in preoperative pelvic chemoradiation schedules for rectal cancer in our centre.

METHOD

Patients treated from January 2005 to June 2007 were included. Information was collected on patient characteristics; treatment details; pathological response to treatment; recurrence and survival. All statistical analyses were performed using SPSS V17.

RESULTS

All patients had pelvic radiation. Ninety-nine patients were treated with capecitabine and 97 with 5-FU. The two groups were well matched for age, sex and TNM stage. There were significantly more PS (performance status) 0 patients in the capecitabine group (51%vs 30%) (P = 0.001). Of the 99 patients in the capecitabine group, 91 (92%) were able to undergo surgery with 84 (93%) achieving R0 resection. In the 5-FU group, these proportions were 87 (90%) and 70 (80%). The difference in the rate of R0 resection was statistically significant (P = 0.024). The APR rate was 35% in the capecitabine group compared with 47% in the 5-FU group (P = 0.06). There was no significant difference in pathological complete response (pCR) rates between capecitabine (14%) and 5-FU(12%). A higher pCR rate (30%) was observed in patients who underwent a brachytherapy boost (P = 0.051). There were three local recurrences in the whole patient group, (capecitabine 1; 5-FU 2). Thirty-five patients had distant metastases, 14 in the capecitabine and 21 in the 5-FU group. There was no significant difference in the risk of recurrence between the two groups. Six patients in each group had grade 3 toxicity with diarrhoea being more common with capecitabine.

CONCLUSIONS

Preoperative chemoradiotherapy with capecitabine for rectal cancer is efficacious and comparable to 5-FU (IV). It is more convenient, is well tolerated and avoids the need for inpatient admission.