Lumboaortic and iliac lymphadenectomy for lymph node recurrence of colorectal cancer: prognostic value of the MSI phenotype

The prognostic factors of primary colorectal sarcoma and the clinical outcomes of negative lymph node dissection

Background

Primary colorectal sarcoma is an extremely rare malignancy that is associated with poor patient outcomes. The aim of this study was to identify the prognostic factors of primary colorectal sarcoma and evaluate the clinical outcomes associated with these prognostic factors.

Methods

Between January 1, 2000 and December 31, 2016, the clinical data of 315 patients with primary colorectal sarcoma were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Cancer-specific survival (CSS) was analyzed by the Kaplan-Meier method and by log-rank test. The prognostic factors were identified by univariate and multivariate Cox regression analysis and hazard ratio (HR) and 95% confidence interval (CI) of covariates were also estimated. The optimal cutoff value for NLN count at dissection was identified using X-tile software and validated by univariate Cox regression analysis.

Results

Of the 315 patients with primary colorectal sarcoma identified, 88.6% received surgery. The median follow-up time was 34 months with an interquartile range (IQR) of 9-79 months. The 5-year rate of CSS was 76.73% and 27.8% for the surgery group and the non-surgery group, respectively (P<0.0001). Univariate and multivariate Cox regression analysis performed on the data of nonmetastatic patients demonstrated that sex, race, radiotherapy, and chemotherapy had no effect on patient CSS, with age, tumor site, tumor grade, and NLN dissection being independent prognostic factors. A significant correlation was found between advanced age (>80 years old) and poor CSS (HR 1.964; 95% CI: 1.005-3.839; P=0.048). There were also significant correlations between colonic tumors and poor CSS (HR 2.903; 95% CI: 1.348-6.250; P=0.006) and grade IV tumors and poor CSS (HR 3.431; 95% CI: 1.725-6.823; P<0.001), while NLN dissection was associated with improved CSS (HR 0.946; 95% CI: 0.911-0.983; P=0.004). X-tile software analysis was used to determine that the optimal cutoff value for NLN count was 13. Patients who received NLN dissection with a cutoff value of 13 or more displayed better CSS than those who did not (P=0.016).

Conclusions

Primary colorectal sarcoma patients can benefit significantly from primary tumor surgery. Age, tumor site, grade and NLN dissection are independent prognostic factors for CSS in nonmetastatic patients. Importantly, nonmetastatic patients treated with NLN dissection with an NLN count of 13 or more have significantly better CSS.

Role of stereotactic body radiotherapy for oligometastasis from colorectal cancer

Systemic chemotherapy has enabled prolongation of survival in patients with stage IV colorectal cancer. This has subsequently increased the relative significance of local therapy for patients with oligometastases because they can be cured by removal of oligometastatic lesions. One of the most frequently reported tumor histologies for oligometastases is colorectal cancer. Resection is the standard therapy in most settings of oligometastases. Recently, studies have shown that stereotactic body radiotherapy (SBRT) may become a treatment option that provides high local control with minimal morbidity. Two-year local control rates following SBRT for hepatic and pulmonary oligometastases are almost over 80% and are even higher for patients treated with high-dose regimens. The indications of SBRT for other metastatic sites or conditions include isolated lymph nodes, spinal and adrenal metastasis, and post-surgical pelvic recurrence. Many retrospective studies have indicated that SBRT for various lesions results in good outcomes with low morbidity, both in the curative and palliative setting. However, few reports with a high level of evidence have indicated the efficacy of SBRT compared to standard therapy. Hereafter, the optimal indication of SBRT needs to be prospectively investigated to obtain convincing evidence.

Identification of patients likely to benefit from metastasectomy in stage IV colorectal cancer

PURPOSE

The aim of the present study was to determine selection criteria for patients with stage IV colorectal cancer (CRC) who were likely to show survival benefits of metastasectomy.

METHODS

Clinicopathological data of 119 patients with stage IV CRC who underwent primary CRC resection were retrospectively reviewed. The prognostic factors were analyzed according to the disease resectability status, and patients likely to show survival benefits of metastasectomy were identified.

RESULTS

Metastasectomy was performed in 63 patients. Among these patients, R0 resection was reported in 55 patients, who comprised the curable group. The other 64 patients comprised the noncurable group. For the noncurable group, postoperative chemotherapy was identified as the only significant prognostic factor. In the curable group, T stage, histological type, elevated serum carcinoembryonic antigen (CEA) level and the presence of extra hepatic disease were identified as independent prognostic factors. Patients within the curable group were further classified into a low-risk group (zero to two prognostic factors) and a high-risk group (three or more prognostic factors). The overall survival (OS) of the high risk patients in the curable group was as poor as that of the patients in the noncurable group.

CONCLUSIONS

Stage IV CRC patients consisted of heterogeneous populations who had different prognostic factors, stratified by the disease resectability status. No prognostic benefit of metastasectomy was observed in high-risk patients undergoing curative metastasectomy. These results suggested that patients showing survival benefits of metastasectomy can be identified by considering the prognostic factors in patients undergoing curative metastasectomy.

Apoptotic proteins as prognostic markers and indicators of radiochemosensitivity in stage II/III rectal cancers

AIM

The expression of pro-apoptotic (Bax) and anti-apoptotic (mutated p53, Bcl-2, Bclxl) proteins was determined retrospectively using immunohistochemistry in pre-treatment biopsy samples from patients with rectal cancer treated with or without preoperative chemoradiation to investigate their role as prognostic markers and indicators of radiochemosensitivity.

METHOD

Biopsy samples from 67 patients operated for stage II/III rectal cancer and enrolled in an active follow-up programme were examined 8-10 years after surgery. Thirty-three had been treated with immediate surgery followed, in selected cases, by adjuvant postoperative chemoradiation. Thirty-four had preoperative chemoradiation. Immunohistochemical staining was carried out using an automated immunostainer on sections of paraffin-embedded tissue.

RESULTS

Independent prognostic factors for rectal cancer death were pN status (hazard ratio 3.82; 95% CI 1.67-8.73) and a high level of Bclxl positivity (hazard ratio 4.75; 95% CI 2.10-10.72) according to multivariate regression analysis by stepwise selection. Bax expression was associated with downstaging and higher survival in irradiated patients (P = 0.0004).

CONCLUSION

Pretreatment evaluation of apoptotic Bax and anti-apoptotic Bclxl factors in biopsy samples of stage II/III rectal cancers may be helpful in selecting tumours that will respond to chemoradiation or in identifying patients who will have limited benefit from chemoradiation and should therefore be selected for a more aggressive systemic regimen.

[The surgeon and anti-angiogenics]

The surgeon must know the importance of angiogenesis in wound healing. He must also use anti-angiogenics to change the clinical situations and make curative a potentially ineffective surgery. However, these strategies require daily biological indicators able to quantify the tissue activity, that we do not possess yet, nor have we any indicator to predict tumour sensitivity to anti-angiogenics.