The short-term outcomes of induction SOX (S-1 + oxaliplatin) ± cetuximab chemotherapy followed by short-course chemoradiotherapy in patients with poor-risk locally advanced rectal cancer

A review of preoperative chemoradiotherapy for lower rectal cancer

In Western countries, rectal cancer has been treated by chemoradiotherapy (CRT) for several decades now, and good local control has been reported. However, Japanese guidelines did not strongly recommend CRT, because CRT is only useful for achieving local control and imbues no survival benefit. For this reason, CRT was rarely used to treat rectal cancer in Japan. However, in the 2000s, several studies involving CRT began to be reported from Western countries, such as “correlation between pathological complete response and survival,” “induction chemotherapy followed by CRT,” and “watch-and-wait policies.” These studies were directly correlated with survival of and benefits to the patients. Given these findings, Japanese institutions have recently begun to introduce CRT for rectal cancer. Therefore, in the present study, we reviewed several topics regarding CRT for rectal cancer.

Preoperative short course radiotherapy with concurrent and consolidation chemotherapies followed by delayed surgery in locally advanced rectal cancer: preliminary results

PURPOSE

This study aimed to assess complications and outcomes of a new approach, that is, combining short course radiotherapy (SRT), concurrent and consolidative chemotherapies, and delayed surgery.

MATERIALS AND METHODS

In this single arm phase II prospective clinical trial, patients with T3-4 or N+ M0 rectal adenocarcinoma were enrolled. Patients who received induction chemotherapy or previous pelvic radiotherapy were excluded. Study protocol consisted of three-dimensional conformal SRT (25 Gy in 5 fractions in 1 week) with concurrent and consolidation chemotherapies including capecitabine and oxaliplatin. Total mesorectal excision was done at least 8 weeks after the last fraction of radiotherapy. Primary outcome was complete pathologic response and secondary outcomes were treatment related complications.

RESULTS

Thirty-three patients completed the planned preoperative chemoradiation and 26 of them underwent surgery (24 low anterior resection and 2 abdominoperineal resection). Acute proctitis grades 2 and 3 were seen in 11 (33.3%) and 7 (21.2%) patients, respectively. There were no grades 3 and 4 subacute hematologic and non-hematologic (genitourinary and peripheral neuropathy) toxicities and perioperative morbidities such as anastomose leakage. Grade 2 or higher late toxicities were observed among 29.6% of the patients. Complete pathologic response was achieved in 8 (30.8%) patients who underwent surgery. The 3-year overall survival and local control rates were 65% and 94%, respectively.

CONCLUSION

This study showed that SRT combined with concurrent and consolidation chemotherapies followed by delayed surgery is not only feasible and tolerable without significant toxicity but also, associated with promising complete pathologic response rates.

Low expression of the GOPC is a poor prognostic marker in colorectal cancer

The Golgi-associated PDZ- and coiled-coil motif-containing (GOPC) protein controls the intracellular trafficking of numerous integral membrane proteins. Knockdown of GOPC increases activation of the mitogen-activated protein kinase-extracellular signal-regulated kinase 1/2 pathway and cancer cell progression in colorectal cancer. The present study aimed to clarify the correlation between GOPC expression and prognosis in colorectal cancer. Total RNA was extracted from 153 clinical colorectal cancer specimens and GOPC expression was evaluated using reverse transcription-quantitative polymerase chain reaction. The correlation between GOPC expression and clinicopathological factors was analyzed, along with the association of GOPC expression with overall survival (OS) and with recurrence-free survival (RFS). Lower expression of GOPC was significantly associated with a high frequency of venous invasion (P=0.001) and to poorer OS and RFS based on Kaplan-Meier analysis. In addition, multivariate analyses using a Cox proportional hazards model identified lower expression of GOPC to be an independent prognostic factor for colorectal cancer (hazard ratio=2.800; 95% confidence interval; 1.121-7.648; P=0.027). Lower expression of GOPC revealed a high frequency of venous invasion and associated with poorer prognosis for patients with colorectal cancer.

Phase III trial comparing UFT + PSK to UFT + LV in stage IIB, III colorectal cancer (MCSGO-CCTG)

PURPOSE

Oral adjuvant uracil and tegafur plus leucovorin (UFT/LV) is not inferior to standard weekly fluorouracil and folinate for stage II/III colon cancer. However, protein-bound polysaccharide K (PSK) has been evaluated as postoperative adjuvant therapy for colorectal cancer. This report is the first of MCSGO-CCTG, which compared UFT/LV to UFT/PSK as adjuvant chemotherapy for stage IIB or III colorectal cancer in patients who had undergone Japanese D2/D3 lymph node dissection.

METHODS

The primary endpoint was the 3-year disease-free survival (DFS). A randomized non-inferiority study compared UFT/LV to UFT/PSK. The overall survival, adverse events, compliance, and quality of life were also investigated as the secondary endpoints.

RESULTS

Between March 2006 and December 2010, 357 patients were randomized to UFT/PSK (n = 178) or UFT/LV (n = 179) (median age 65 years, colon/rectum 67.4/32.6%, stage IIB/IIIA/IIIB/IIIC 11.1/15.7/55.0/18.2%). The 3-year DFS rate was 82.3% in those receiving UFT/LV and 72.1% in those receiving UFT/PSK. The non-inferiority of UFT/PSK adjuvant therapy to UFT/LV therapy was not verified (-9.06%, 90% confidence interval -17.06 to -1.06%). The 3-year overall survival rate was 95.4% in those receiving UFT/LV and 90.7% in those receiving UFT/PSK.

CONCLUSIONS

As adjuvant chemotherapy for stage IIB and III colorectal cancer patients, UFT/PSK adjuvant therapy was not non-inferior to UFT/LV therapy with respect to the DFS.

Impact of capecitabine and S-1 on anticoagulant activity of warfarin in patients with gastrointestinal cancer

PURPOSE

Capecitabine and S-1 are orally administered fluoropyrimidine anticancer drugs widely used to treat gastrointestinal cancer. While anticoagulant therapy for cancer patients is recommended, many studies have shown that the effects of warfarin are enhanced by its interaction with fluoropyrimidine. We investigated the effects of capecitabine or S-1 on the anticoagulant activity of warfarin in patients coadministered both drugs.

METHODS

We retrospectively investigated the clinical features of and anticoagulant activity in nine consecutive patients who received capecitabine or S-1 in combination with warfarin from January 2008 to December 2014 at our institution. The prothrombin time international normalized ratio divided by current warfarin dosage (PT-INR/dose) was measured over time to evaluate warfarin titer in each patient.

RESULTS

Reductions in warfarin dosage were required, from 2.6 mg/day before chemotherapy to a minimum of 1.7 mg/day after chemotherapy initiation, on average. The median time until the first dosage reduction after initiation was 22 days for the capecitabine group and 43 days for the S-1 group. The median time until minimal dosage of warfarin was reached was 43 days in both groups. PT-INR/dose was elevated from 0.85 before chemotherapy to a maximum of 1.41 after its initiation. The median time until the maximal PT-INR/dose was reached was 46 days for the capecitabine group and 46.5 days for the S-1 group.

CONCLUSIONS

The anticoagulant activity of warfarin may be enhanced by coadministration with capecitabine or S-1. Close monitoring of anticoagulant activity is required to avoid a hyperfibrinolytic state due to a severe adverse interaction.