Outcome of patients with clinical stage II or III rectal cancer treated without adjuvant radiotherapy

Mechanisms and Clinical Significance of Tumor Lymphatic Invasion

Tumor-associated lymphatic vessels play an important role in tumor progression, mediating lymphatic dissemination of malignant cells to tumor-draining lymph nodes and regulating tumor immunity. An early, necessary step in the lymphatic metastasis cascade is the invasion of lymphatic vessels by tumor cell clusters or single tumor cells. In this review, we discuss our current understanding of the underlying cellular and molecular mechanisms, which include tumor-specific as well as normal, developmental and immunological processes “hijacked” by tumor cells to gain access to the lymphatic system. Furthermore, we summarize the prognostic value of lymphatic invasion, discuss its relationship with local recurrence, lymph node and distant metastasis, and highlight potential therapeutic options and challenges.

Left colon as a novel high-risk factor for postoperative recurrence of stage II colon cancer

Background

It is not clear whether stage II colon and rectal cancer have the same risk factors for recurrence. Thus, the purpose of this study was to identify the risk factors for postoperative recurrence in stage II colorectal cancer.

Patients and methods

We retrospectively analyzed the data of 990 patients who had undergone radical surgery for stage II colorectal cancer. Patients’ pathological features and characteristics including age, sex, family history, body mass index, tumor diameter, gross type of tumor, infiltration degree (T3/T4), tumor grade, perineural invasion, vascular invasion, lymphatic invasion, pathologic examination of lymph node number, and preoperative carcinoembryonic assay (CEA) level was compared between patients with and without recurrence. Finally, the prediction of the left and right colons was analyzed.

Results

The mean ages of the colon cancer and rectal cancer patients were 69.5 years and 66.4 years, respectively. In total, 508 (82.1%) and 285 (76.8%) patients were treated laparoscopically for colon cancer and rectal cancer, respectively, with median follow-up periods of 42.2 months and 41.8 months, respectively. Forty-four recurrences occurred in both the colon cancer (7.1%) and rectal cancer (11.9%) groups. The preoperative serum CEA level and T4 infiltration were significantly higher in recurrent colorectal cancer patients. The postoperative recurrence rate of left colon cancer (descending colon, sigmoid colon) was higher than that of right colon cancer (cecum, ascending colon, transverse colon) (OR 2.191, 95% CI 1.091–4.400, P = 0.027). In COX survival factor analysis of colon cancer, the left colon is one of the independent risk factors (risk ratio 5.377, 95% CI 0.216–0.88, P = 0.02). In disease-free survival (DFS), the left colon has a relatively poor prognosis (P = 0.05). However, in the COX analysis and prognosis analysis of OS, no difference was found between the left colon and the right colon.

Conclusion

Preoperative CEA and depth of infiltration (T4) are high-risk factors associated with recurrence and are prognostic factors in stage II colorectal cancer. Left colon is also a risk factor for postoperative recurrence of stage II colon cancer.

Pathological complete response after preoperative chemotherapy including FOLFOX plus bevacizumab for locally advanced rectal cancer: A case report and literature review

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Preoperative chemotherapy alone for locally advanced rectal cancer remain unclear.

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Neoadjuvant chemotherapy was a promising treatment for unresectable rectal cancer.

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Earlier preoperative systemic chemotherapy was assumed to prevent the dissemination.

Background

In Japan, the significance and efficacy of preoperative chemotherapy alone for locally advanced rectal cancer remain controversial. This case report presents the apparent effectiveness of preoperative FOLFOX plus bevacizumab as shown by pathological complete response (pCR). Additionally, we review the relevant literature and discuss the clinical management of locally advanced rectal cancer with preoperative chemotherapy.

Case presentation

A 59-year-old male presented with severe constipation, bloody stool and a loss of 10% of his body weight over 3 months. Preoperative examination revealed locally advanced rectal cancer with extensive invasion of the bladder wall and enlarged regional lymph nodes. Thus, this lesion was assigned a preoperative classification of T4bN2bM0 stage IIIC according to the 8^th Union for International Cancer Control (UICC) guidelines. Therefore, the patient initially underwent an external loop colostomy of the transverse colon. Next, the patient received chemotherapy including FOLFOX plus bevacizumab. After 12 cycles of chemotherapy, the tumor size was markedly decreased, and all lymph node metastases had disappeared. Therefore, the patient underwent conventional resection of the rectum with D3 lymph node dissection and closure of the colostomy. Histopathological analysis of the resected specimen revealed that all lesions were fibrotic and devoid of any viable cancer cells. Thus, this lesion was assigned a final classification of ypT0N0M0 stage 0.

Conclusions

We present the rare case of a patient with surgically resected locally advanced rectal cancer who demonstrated an impressive pCR with preoperative chemotherapy, which included FOLFOX plus bevacizumab.

A prospective feasibility study to evaluate neoadjuvant-synchronous S-1 with radiotherapy for locally advanced rectal cancer: A multicentre phase II trial

Treatment results of locally advanced rectal cancer without preoperative chemoradiotherapy (CRT) in Japan do not differ from those of Western countries. Preoperative CRT with new anticancer agents may decrease local recurrence rate and prevent distant metastases, thus improving survival. We conducted a trial to evaluate feasibility of neoadjuvant CRT using S-1 in patients with locally advanced rectal cancer. A multi-institutional (17 specialized centres), interventional, phase II trial was conducted from April 2009 to August 2011. Patients fulfilling the following requirements before neoadjuvant CRT were included: histologically proven rectal carcinoma; tumour in the upper or lower rectum; cancer classified as T3-4 N0-3 M0. Neoadjuvant CRT with S-1 (80 mg/m²/day on days 1-5, 8-12, 22-26, and 29-33) and irradiation (total 45 Gy/25 fr, 1.8 Gy/day, on days 1-5, 8-12, 15-19, 22-26, and 29-33) was performed. Total mesorectal excision with D3 lymphadenectomy was performed during weeks 4 and 8 after completion of neoadjuvant CRT. The primary endpoint was completion rate of neoadjuvant CRT. Secondary endpoints were response rate to neoadjuvant CRT, short-term clinical outcomes, curative resection rate, and pathologic response (grade 2/3). Of the 37 patients included, 86.5% completed neoadjuvant CRT (95% CI, 75.5-97.5%), and 10.8% (4) experienced an adverse event (grade 3/4). Response rate (RECIST 1.0) was 56.8% (95% CI, 40.8-72.7%), and pathologic response rate was 48.6% (95% CI, 32.5-64.8%). This study demonstrated that neoadjuvant-synchronous S-1+radiotherapy for locally advanced rectal cancer was feasible in terms of pathologic response and adverse events. Registration number: UMIN-CTR, No. C003396.

Neoadjuvant oxaliplatin and capecitabine and bevacizumab without radiotherapy for poor-risk rectal cancer: N-SOG 03 Phase II trial

OBJECTIVE

This Phase II trial was designed to evaluate the safety and efficacy of neoadjuvant oxaliplatin and capecitabine and bevacizumab without radiotherapy in patients with poor-risk rectal cancer.

METHODS

Patients with magnetic resonance imaging-defined poor-risk rectal cancer received neoadjuvant oxaliplatin and capecitabine and bevacizumab followed by total mesorectal excision or more extensive surgery.

RESULTS

Between February 2010 and December 2011, 32 patients were enrolled in this study. The completion rate of the scheduled chemotherapy was 91%. Reasons for withdrawal were refusal to continue therapy in two patients and disease progression in one, with two of these three patients not undergoing surgery. Among the 29 patients who completed the scheduled chemotherapy, one refused surgery within 8 weeks after the completion of chemotherapy, which was the period stipulated by the protocol, and another had rectal perforation, requiring urgent laparotomy. As a result, the completion rate of this experimental treatment was 84%. Of the 30 patients who underwent surgery, the R0 resection rate was 90% and a postoperative complication occurred in 43%. A pathological complete response was observed in 13% and good tumor regression was exhibited in 37%.

CONCLUSIONS

Neoadjuvant oxaliplatin and capecitabine plus bevacizumab for poor-risk rectal cancer caused a high rate of anastomotic leakage and experienced a case with perforation during chemotherapy, both of which were bevacizumab-related toxicity. Although the short-term results with the completion rate of 84.4% and the pathological complete response rate of 13.3% were satisfactory, we have to reconsider the necessity of bevacizumab in neoadjuvant chemotherapy (UMIN number, 000003507).

Should quality measures for lymph node dissection in colon cancer be extrapolated to rectal cancer?

BACKGROUND

A minimum of 12 lymph nodes has been endorsed as a quality measure to confirm node-negative colon cancer, but its relevance to early-stage rectal cancer is unclear.

METHODS

Patients with stage I or II rectal cancer from the Surveillance, Epidemiology and End Results tumor registries from 1998 to 2002 were identified. Patients were grouped by the number of lymph nodes sampled. Groups were compared for patient demographics, tumor characteristics, and 5-year overall survival.

RESULTS

Of the 6,214 patients (57% men) identified, only 33% had ≥12 lymph nodes examined in the surgical specimen. Multivariate analysis identified sex, race, age, T stage, and number of lymph nodes examined as independent predictors of 5-year overall survival.

CONCLUSIONS

Five-year overall survival improved as the number of sampled nodes increased. A thorough lymphadenectomy should routinely be performed to optimize staging and to improve survival of patients with early-stage rectal cancer.

Phase II trial of neoadjuvant chemotherapy with XELOX plus bevacizumab for locally advanced rectal cancer

In Western countries, the standard treatment for locally advanced rectal cancer is preoperative chemoradiotherapy followed by total mesorectal excision. On the other hand, in Japan, treatment results without radiotherapy are by no means inferior; therefore, extrapolation of results of preoperative treatment in Western countries to Japan is controversial. We consider that survival may be improved by preoperative treatment with new anticancer agents as they are expected not only to decrease the local recurrence rate but also to prevent distant metastases. We are conducting a multicentre Phase II study to evaluate the safety and efficacy of neoadjuvant chemotherapy using XELOX plus bevacizumab without radiotherapy in patients with locally advanced rectal cancer. The primary endpoint of the study is treatment compliance. Secondary endpoints are overall survival, disease-free survival, local recurrence-free survival, objective response rate, R0 resection rate and adverse events. Thirty patients are required for this study.

Clinical characteristics of rectal cancer involving the anal canal

BACKGROUND

This study evaluates the clinical characteristics of rectal cancer involving the anal canal.

METHODS

A total of 346 consecutive patients with primary low rectal cancer located below the peritoneal reflection were reviewed in this study. Patients were divided into two groups according to whether the lower edge of the tumor came in contact with the anal canal (P group, n = 78) or not (Rb group, n = 268). Clinical and pathological parameters, recurrence rates, and survival rates were compared between the two groups.

RESULTS

The occurrence of uncommon histological types of tumor was significantly higher in the P group than in the Rb group. P group patients also had a significantly higher lateral pelvic node metastasis rate (p < 0.001), lower 5-year overall survival rate (p = 0.0491), and higher 5-year local recurrence rate (p = 0.0171) than Rb group patients. Multivariate analysis revealed that tumor location was a significant risk factor for local recurrence. In the P group, multivariate analysis showed that uncommon histological tumor types were a significant prognostic factor.

CONCLUSION

Rectal cancer involving the anal canal should be treated with special care, considering the particularly high lateral pelvic lymph node metastasis rate and high local recurrence rate.

Adjuvant radiotherapy following total mesorectal excision for stage IIA rectal cancer: is it beneficial?

PURPOSE

The benefit of adjuvant radiotherapy in patients with stage IIA (T3N0) rectal cancer following total mesorectal excision (TME) is controversial. We evaluated the effect of adjuvant chemoradiotherapy (CRT) versus chemotherapy (CT) alone on the local recurrence and survival of patients with stage IIA rectal cancer after TME.

METHODS

Between 1996 and 2004, patients with stage IIA rectal cancer who received adjuvant CT (n = 29) or CRT (n = 122) following TME were enrolled. Oncologic outcomes were compared between groups, and risk factors for local recurrence and overall survival rates were analyzed.

RESULTS

The median follow-up period was 78 months. No significant differences were observed in the 5-year local recurrence (3.4% versus 9.0%; P = 0.348) or 5-year overall survival rates (86.2% versus 80.3%; P = 0.924) between CT and CRT. However, involvement of the circumferential resection margin and age >60 years were associated with adverse oncologic outcomes.

CONCLUSIONS

Additional postoperative radiotherapy did not alter local recurrence or survival after TME in patients with stage IIA rectal cancer. Postoperative radiation may be an overtreatment as an adjuvant therapy in patients with stage IIA rectal cancer if they had no other risk factors. However, randomized controlled trials are warranted to confirm this suggestion.

Regional lymph node metastasis and locoregional recurrence of rectal carcinoma in the era of TME [corrected] surgery. Implications for treatment decisions

BACKGROUND AND AIMS

For rectal carcinoma treated according to the concept of total mesorectal excision (TME surgery), the independent influence of regional lymph node metastasis on the locoregional recurrence risk is still in discussion. A reliable assessment of this risk is important for an individualised selective indication for neoadjuvant radio-/radiochemotherapy.

METHODS

Analysis of literature, especially of the last 20 years, and consideration of pathological and oncological basic research. Multivariate analysis of data of the Erlangen Registry of Colorectal Carcinoma.

RESULTS

The clinical assessment of the pretherapeutic regional lymph node status by the present available imaging methods is still unreliable. The analysis of the association between pretherapeutic regional lymph node status and locoregional recurrence risk has to be based on follow-up data of patients treated by primary surgery and has to be distinguished between patients treated by conventional and optimised quality-assured TME surgery, respectively. Data from Erlangen show an increase of the local recurrence risk for patients with at least four involved regional lymph nodes.

CONCLUSIONS

For patients with at least four involved regional lymph nodes, a neoadjuvant radiochemotherapy may be indicated. However, today, the pretherapeutic diagnosis is uncertain and results in overtherapy in 40%. Thus, in case of positive lymph node findings by imaging methods, the benefits and risk of neoadjuvant therapy in such situations should always be discussed with the patient in the sense of informed consent and shared decision.