Neoadjuvant chemotherapy without radiotherapy for locally advanced rectal cancer

Relationship between stromal regulatory T cells and the response to neoadjuvant chemotherapy for locally advanced rectal cancer

BACKGROUND

In addition to the direct power of anticancer drugs, the effectiveness of anticancer therapy depends on the host immune function. The present study investigated whether or not the reduction rate and histological response of preoperative chemotherapy were related to the immune microenvironment surrounding a primary tumor of the rectum.

METHODS

Sixty-five patients received preoperative chemotherapy followed by resection from 2012 to 2014; all of these patients were retrospectively analyzed. CD3, CD8, and FoxP3 were immunohistochemically examined as markers for T lymphocytes, cytotoxic T lymphocytes, and regulatory T lymphocytes (Treg), respectively. The correlation between the tumor-infiltrating lymphocyte composition and the tumor reduction rate and histological response to neoadjuvant chemotherapy was investigated.

RESULTS

The average tumor reduction rate was 41.5% ± 18.8%. According to RECIST, 47 patients (72.3%) achieved a partial response (PR), and 1 patient (1.5%) achieved a complete response (CR). Eight patients (12.3%) showed a grade 2 histological response, and 2 (3.1%) showed a grade 3 response. A multivariate analysis demonstrated that a low Treg infiltration in stromal cell areas was significantly associated with the achievement of a PR or CR [odds ratio (OR) 7.69; 95% confidence interval (CI) 1.96-33.33; p < 0.01] and a histological grade 2 or 3 response (OR 11.11; 95% CI 1.37-98.04; p = 0.02).

CONCLUSION

A low Treg infiltration in the stromal cell areas may be a marker of a good response to neoadjuvant chemotherapy in patients with locally advanced rectal cancer.

Neoadjuvant radiotherapy for locoregional Siewert type II gastroesophageal junction adenocarcinoma: A propensity scores matching analysis

OBJECTIVE

To analyze the effect of neoadjuvant radiotherapy (nRT) on prognosis in patients with locoregional Siewert type II gastroesophageal junction adenocarcinoma (GEA).

METHOD

All patients pathologically diagnosed as Siewert type II GEA between 2004 and 2015 were retrieved from the Surveillance, Epidemiology and Final Results (SEER) database. We analyzed the impact of different treatment regimens on the prognosis in each stage. Survival analysis was performed by Kaplan-Meier (K-M) method. Multivariate Cox model and propensity score matching was further used to verify the results.

RESULTS

4,160 patients were included in this study. The efficacy of nRT was superior to that of adjuvant radiotherapy (aRT) (p = 0.048), which was the same as that of surgery combined with chemotherapy (p = 0.836), but inferior to the overall survival (OS) of surgical treatment alone (p<0.001) in T1-2N0M0 patients. Patients receiving nRT had distinctly better survival than those receiving surgical treatment alone (p = 0.008), but had similar survival compared with patients treated with aRT (p = 0.989) or surgery combined with chemotherapy (p = 0.205) in the T3N0/T1-3N+M0 subgroup. The efficacy of nRT is clearly stronger than that of surgical therapy alone (p<0.001), surgery combined with chemotherapy (p<0.001), and aRT (p = 0.008) in patients with T4 stage. The survival analysis results were consistent before and after propensity score matching.

CONCLUSION

In these carefully selected patients, the present study made the following recommendations: nRT can improve the prognosis of patients with T3N0M0/T1-3N+M0 and T4 Siewert type II GEA, and it seems to be a better treatment for T4 patients. Surgery alone seems to be sufficient, and nRT is not conducive to prolonging the survival of Siewert II GEA patients with T1-2N0M0 stage. Of course, further prospective trials are needed to verify this conclusion.

Total neoadjuvant therapy for rectal cancer: Making sense of the results from the RAPIDO and PRODIGE 23 trials

A few months ago, results from two randomised phase III trials of total neoadjuvant therapy (TNT) in locally advanced rectal cancer were presented (RAPIDO and PRODIGE 23), consistently showing better short- and long-term outcomes with TNT as compared with standard neoadjuvant long-course chemoradiotherapy (CRT) or short-course radiotherapy (SCRT). These results represent corroborating evidence in support of a practice that many centres had already implemented based on promising preliminary data. Also, they provide new, high-level evidence to endorse TNT as a new management option in the treatment algorithm of stage II-III rectal cancer in those centres where CRT and SCRT have long remained the only accepted standard neoadjuvant treatments. Having two consistently positive trials is certainly reassuring regarding the potential of TNT as a general treatment approach. Nevertheless, substantial differences between these trials pose important challenges in relation to the generalisability and applicability of their results, and translation of the same into practical clinical recommendations. In this article, we address a number of key questions that the RAPIDO and PRODIGE 23 trials have raised among the broad community of gastrointestinal oncologists, proposing an interpretation of the data that may help the decision making, and highlighting grey areas that warrant further investigation.

Colorectal Cancer in the Elderly Patient: The Role of Neo-adjuvant Therapy

BACKGROUND

Neoadjuvant chemoradiotherapy has a significant role in downstaging cancer. It improves the local control of the disease and can make conservative resection of rectal cancer possible.

METHODS

We enrolled 114 patients with subperitoneal rectal cancer who underwent neoadjuvant chemoradio-therapy and radical excision with total mesorectal excision (TME). The primary endpoint was oncological outcomes and the secondary endpoint was surgical outcomes.We evaluate the experience of a multidisciplinary team and the role of neoadjuvant chemoradiotherapy in integrated treatment of cancer of the subperitoneal rectum.

RESULTS

Surgical procedures performed were abdominal perineal resection in 4 cases (3.5%), anterior resection in 89 cases (78%), Hartmann's procedure in 5 cases (4.4%), and ultralow resection with coloanal anastomosis and diverting stoma in 16 patients (14%).Local recurrence occurred in 6 patients (5.2%), the overall survival was 71.9% at 5 years and disease-free survival was about 60%.

CONCLUSIONS

The effect of pathological downstaging amounted to 58.8%, including cPR. The pathologic complete remission occurred in 8.8% of cases.The outcomes of neoadjuvant therapy can be achieved when this treatment is associated with correct surgical technique with TME and the prognosis is defined by an anatomopathological examination performed according to Quirke's protocol.

Complete pathological response following neoadjuvant FOLFOX chemotherapy in BRCA2-mutant locally advanced rectal cancer: a case report

BACKGROUND

Patients with locally advanced rectal cancer (LARC) achieving a pathological complete response (pCR) to neoadjuvant treatment usually have a good prognosis, but only accounted for less than 20%.

CASE PRESENTATION

We report a case of a 25-year-old male with LARC treated with neoadjuvant FOLFOX chemotherapy, and experienced a pCR. The next-generation sequencing analysis revealed the presence of breast cancer gene 2 (BRCA2) somatic mutation and an increased somatic mutational load without microsatellite instability (MSI). To our knowledge, this is the first report of BRCA2 mutant LARC that demonstrated significant benefit from FOLFOX neoadjuvant treatment.

CONCLUSIONS

This case indicated an association of BRCA2 mutation with high mutation loads and an excellent response of oxaliplatin-based chemotherapy regimen for LARC. Our findings encourage further studies to analyze BRCA mutations in patients with LARC, especially for those patients unable or unwilling to receive radiotherapy.

Session 2: Are we ready for primary chemotherapy in rectal cancer: who, when, why?

The potential of preoperative chemotherapy in rectal cancer is the subject of investigation in a number of global randomized trials. In this overview and expert discussion, Professor Cervantes summarizes the findings of numerous Phase II trials testing neoadjuvant chemotherapy. The crucial points in the next phase of trials include: patient selection, whether radiotherapy can be omitted altogether and whether chemotherapy can be used to augment the initial response to chemoradiotherapy. Finally, with the emergence of Magnetic Resonance Tumour Regression Grade a reliable method for assessing response after initial chemoradiotherapy, we ask if this can be used to drive the use of further selective chemotherapy to augment response.

Tailored Treatment Strategy for Locally Advanced Rectal Carcinoma Based on the Tumor Response to Induction Chemotherapy: Preliminary Results of the French Phase II Multicenter GRECCAR4 Trial

BACKGROUND

Preoperative radiochemotherapy and total mesorectal excision are the standard-of-care for locally advanced rectal carcinoma, but some patients could be over- or undertreated.

OBJECTIVE

This study aimed to assess the feasibility of radiochemotherapy tailored based on the tumor response to induction chemotherapy (FOLFIRINOX) to obtain a minimum R0 resection rate of 90% in the 4 arms of the study.

DESIGN

This study is a multicenter randomized trial (NCT01333709).

SETTING

This study was conducted at 16 French cancer specialty centers.

PATIENTS

Two hundred six patients with locally advanced rectal carcinoma were enrolled between 2011 and 2014.

INTERVENTIONS

Good responders (≥75% tumor volume reduction) were randomly assigned to immediate surgery (arm A) or standard radiochemotherapy (Cap 50: 50 Gy irradiation and 1600 mg/m oral capecitabine daily) plus surgery (arm B). Poor responders were randomly assigned to Cap 50 (arm C) or intensive radiochemotherapy (Cap 60, 60 Gy irradiation, arm D) before surgery.

OUTCOME MEASURES

The primary end point was a R0 resection rate (circumferential resection margin >1 mm).

STATISTICAL CONSIDERATIONS

The experimental strategies were to be considered effective if at least 28 successes (R0 resection) among 31 patients in each arm of stratum I and 34 successes among 40 patients in each arm of stratum II were reported (Simon 2-stage design).

RESULTS

After induction treatment (good compliance), 194 patients were classified as good (n = 30, 15%) or poor (n = 164, 85%) responders who were included in arms A and B (16 and 14 patients) and arms C and D (113 and 51 patients). The trial was prematurely stopped because of low accrual in arms A and B and recruitment completion in arms C and D. Data from 133 randomly assigned patients were analyzed: 11, 19, 52, and 51 patients in arms A, B, C, and D. Good responders had smaller tumors than poor responders (23 cm vs 45 cm; p < 0.001). The surgical procedure was similar among groups. The R0 resection rates [90% CI] were 100% [70-100], 100% [85-100], 83% [72-91], and 88% [77-95]. Among the first 40 patients, 34 successes were reported in arms C and D (85% R0 resection rate). The circumferential resection margin ≤1 rates were 0%, 0%, 12%, and 5% in arms A, B, C, and D. The rate of transformation from positive to negative circumferential resection margin was 93%.

LIMITATIONS

There was low accrual in arms A and B.

CONCLUSION

Tailoring preoperative radiochemotherapy based on the induction treatment response appears safe for poor responders and promising for good responders. Long-term clinical results are needed to confirm its efficacy. See Video Abstract at http://links.lww.com/DCR/A359.

What has preoperative radio(chemo)therapy brought to localized rectal cancer patients in terms of perioperative and long-term outcomes over the past decades? A systematic review and meta-analysis based on 41,121 patients

We asked what preoperative radiotherapy/chemoradiotherapy (PRT/PCRT) has brought to patients in terms of perioperative and long-term outcomes over the past decades. A systematic review and meta-analysis was conducted using PubMed, Embase and Web of Science databases. All original comparative studies published in English that were related to PRT/PCRT and surgical resection and which analyzed survival, postoperative and quality of life outcomes were included. Data synthesis and statistical analysis were carried out using Stata software. Data from 106 comparative studies based on 80 different trials enrolling 41,121 patients were included in our study. Based on our overall analyses, PRT/PCRT significantly improved patients' local recurrence-free survival (LRFS), but neither overall survival (OS) nor metastasis-free survival (MFS) showed improvement. In addition, PRT significantly increased the postoperative morbidity and mortality but PCRT did not have a significant effect. Furthermore, PRT/PCRT significantly increased the risk of postoperative wound complications but not anastomotic leakage and bowel obstruction. Our comprehensive subgroup analyses further supported the aforementioned results. Meanwhile, long-term anorectal symptoms (impaired squeeze pressures, use of pads, incontinence and urgency) and erectile dysfunction were also significantly increased in patients after PRT/PCRT. The benefits of PRT/PCRT as applied over the last several decades have not been sufficient to improve OS. Metastases of primary tumor and postoperative adverse effects were the two primary obstacles for an improved OS. In fact, the greatest advantage of PRT/PCRT is still local tumor control and a significantly improved LRFS.

Efficacy and safety of neoadjuvant chemotherapy with oxaliplatin, 5-fluorouracil, and levofolinate for T3 or T4 stage II/III rectal cancer: the FACT trial

PURPOSE

A multicenter phase II clinical study was performed in patients with T3 or T4 stage II/III rectal cancer to evaluate the efficacy and safety of neoadjuvant chemotherapy with 5-fluorouracil, levofolinate, and oxaliplatin (mFOLFOX6).

METHODS

Patients received four 2-week cycles of mFOLFOX6 therapy (oxaliplatin at 85 mg/m2 + leucovorin at 200 mg/m2 + fluorouracil as a 400 mg/m2 bolus followed by infusion of 2400 mg/m2 over 46 h, all on Day 1). They were evaluated by computed tomography after completion of the fourth cycle. If there was no disease progression, two additional cycles were administered and then surgery was performed. Adjuvant chemotherapy was generally administered for 6 months using appropriate regimens at the discretion of the physician.

RESULTS

mFOLFOX6 therapy was given to 52 patients with locally advanced rectal cancer. The preoperative response rate was 48.8% and the operation rate was 80.8%. Serious adverse events of Grade 3-4 were neutropenia (n = 5), leukopenia (n = 1), thrombocytopenia (n = 1), febrile neutropenia (n = 1), nausea (n = 1), vomiting (n = 1), and peripheral neuropathy (n = 2). The R0 resection rate, pathologic complete response rate, and sphincter preservation rate were 91.0, 11.9, and 73.8%, respectively. Postoperative complications were tolerable.

CONCLUSIONS

The present results suggested that neoadjuvant therapy with mFOLFOX6 is safe and effective, representing a reasonable treatment option for locally advanced rectal cancer.

Timing of Therapies in the Multidisciplinary Treatment of Locally Advanced Rectal Cancer: Available Evidence and Implications for Routine Practice

A multimodality disciplinary approach is paramount for the management of locally advanced rectal cancer. Over the last decade, (chemo)radiotherapy followed by surgery plus or minus adjuvant chemotherapy has represented the mainstay of treatment for this disease. Nevertheless, robust evidence suggesting the optimal timing and sequence of therapies in this setting has been overall limited. A number of questions are still unsolved including the length of the interval between neoadjuvant radiotherapy and surgery or the timing of systemic chemotherapy. Interestingly, emerging data support the contention that altering sequence or timing or both of the components of this multimodality approach may provide an opportunity to implement treatment strategies that far better address the risk and expectations of individual patients. In this article, we review the available evidence on timing of therapies in the multidisciplinary treatment of locally advanced rectal cancer and discuss the potential implications for routine practice that may derive from a change of the currently accepted treatment paradigm.

Recent advances in multidisciplinary approach for rectal cancer

Surgery is a major treatment option for rectal cancer, and total mesorectal excision has been demonstrated to be advantageous in terms of oncological outcome and thus has been the standard surgical approach. Radiotherapy before or after radical surgery is the optimal treatment to control local recurrence of advanced rectal cancer. To date, in many countries, the combination of neoadjuvant concurrent chemotherapy and radiotherapy is considered the standard therapy. A more recent interest in neoadjuvant therapy has been the use of oxaliplatin or targeted agents for neoadjuvant chemoradiotherapy. However, despite many trials of oxaliplatin and targeted agents, 5-FU-based concurrent chemoradiotherapy has remained the only standard treatment option. Postoperative adjuvant chemotherapy with neoadjuvant chemoradiotherapy or induction chemotherapy with neoadjuvant chemoradiotherapy may further improve patient survival, as some clinical studies recently indicated. In Japan, neoadjuvant therapy is not the standard treatment method, because surgery with lateral lymph node dissection is usually performed and this type of surgery may reduce recurrence rate as does radiation therapy. The phase III study to evaluate the oncological effect of the Japanese standard operation (mesorectal excision, ME) with lateral lymph node dissection in comparison with ME alone for clinical stage II and III lower rectal cancer is currently ongoing.