In the present study, we surveyed the rate of control of CINV in 779 patients who received 5511 cycles of chemotherapy regimens in our outpatient cancer chemotherapy clinic. Among them, patients with gastrointestinal cancer were predominant (51 % of patients and 57 % of chemotherapy cycles).
According to the clinical practice guidelines for antiemesis formulated by ASCO [4], MASCC/ESMO [5], NCCN [6], and JSCO [7], palonosetron, a long-acting second-generation 5-HT3 receptor antagonist, is recommended for use in HEC and MEC; however, in the present study, the first generation of 5-HT3 receptor antagonists such as granisetron was predominantly prescribed. In the present study, health professionals, including pharmacists and nurses, interviewed all patients and monitored adverse drug reactions. In addition, we checked the prescription for antiemetic medication and aggressively promoted the appropriate use of antiemetic drugs. As a consequence, adherence to the clinical practice guideline for the use of antiemetic drugs was generally high (76 % for HEC, 88 % for MEC, 99 % for low-risk) for patients receiving the first cycle of chemotherapy, except for those undergoing CDDP-containing regimens (25 %). In the CDDP-containing regimens used in the present study, the dose of CDDP was low (25–30 mg/m2); thus, aprepitant was excluded from the standard medication for HEC. Even such an antiemetic medication effectively prevented nausea and vomiting, in which the overall control rate was 88 % for nausea and 94 % for vomiting. Very recently, Tamura et al. [19] reported the effectiveness of the antiemetic guideline by a multi-institutional prospective observational study, showing that adherence to the guideline is approximately 74 % for HEC and 95 % for MEC. They also reported that adherence (three antiemetics containing aprepitant, 5-HT3 receptor antagonist, and dexamethasone) for HEC decreases the risk for delayed vomiting as compared with two antiemetics (5-HT3 receptor antagonist and dexamethasone) without marked influence on the control of nausea. In the present study, the rate of guideline consistency was generally consistent with the data reported by Tamura et al. [19], although the non-adherence did not affect the control of overall nausea or vomiting.
Under the condition of roughly consistent with guideline-recommended antiemetic medication, vomiting was fairly well controlled, but complete protection from nausea was not sufficient for HEC and MEC. The poor control of nausea for HEC in the first cycle occurred primarily in the A/C regimen for breast cancer. Tamura et al. [19] also reported the high incidence of delayed nausea (49.4 % for HEC and 41.7 % for MEC), with a limited incidence of vomiting.
It was notable that the control of nausea and vomiting was generally higher in the overall cycles than in the first cycle. Particularly, marked improvement of the control rate of delayed nausea was observed at the second and third cycles of A/C chemotherapy. It is unlikely that improvement of the control of nausea results from decrease in the dose of anticancer drugs because, in the present study, the dose reduction was not observed in the first cycle but was carried out in one patient in the second cycle (15 % reduction) as well as in the third cycle (15 % reduction). Patients who showed failure in the control of CINV in the previous cycle were administered prochlorperazine or olanzapine in addition to an antianxiety drug such as lorazepam in the following cycles, which may be the predominant reason for the improvement of CINV control in the subsequent cycles. Moreover, in 608 patients who received the first cycle of HEC, MEC, low, or minimal risk of chemotherapy, the dose intensity was quite similar between patients with and without complete protection from nausea, in which the values were 97.0 ± 8.1 % (mean ± SD) in 450 patients who showed complete protection from nausea and 97.0 ± 7.5 % in 158 patients who did not. In addition, the complete protection from nausea was 71.4 % (60 of 84 patients) in patients with dose reduction and 74.4 % (390 of 524 patients) in those without dose reduction (P = 0.654 by χ
2 test). Therefore, it is unlikely that the dose of anticancer drugs affected the control of chemotherapy-induced nausea in the present study.
Several investigators have shown the risk factors for CINV. Female gender, age, no history of drinking, and history of hyperemesis gravidarum are common as risks that lead to a loss of control of CINV [19–26]. Sekine et al. [21] showed in patients receiving HEC or MEC that female gender has high risk (OR 2.49) for failure in complete response (no vomiting and no rescue). It has also been reported that female patients are more likely to experience nausea and vomiting than male patients receiving HEC or MEC [22, 23]. On the other hand, Hesketh et al. [24] reported in patients receiving CDDP (≥70 mg/m2) that females are at high risk for the inability to complete response (OR 1.303) only when aprepitant is not included in the antiemetic medication. Younger age is also a risk for the loss of emetic control, but the cutoff age differs among studies, ranging from 40 to 65 years old [20–23]. Tamura et al. [19] also reported that older age is a decreased risk for CINV. However, the cutoff value of age that influences the control of CINV is still unclear. In the present study, the cutoff value of age was estimated from the ROC curve method, in which the AUC was 0.658 for nausea (low accuracy prediction) and 0.721 for vomiting (moderate accuracy prediction). The cutoff age was 58.5 years old as determined by the Youden index or 61.5 years old by the distance method and was set at 60 years old. Interestingly, the cutoff age for vomiting predicted by Youden index and distance method (49.5 years old) was younger than that for nausea. As a consequence, age under 60 years old was a significant risk for nausea (OR 2.303; 95 % CI, 1.525–3.477, P < 0.001), whereas age under 50 years old was a significant risk for vomiting (OR 5.803; 95 % CI, 2.667–12.63, P < 0.001). In addition, female gender (OR 1.615; 1.022–2.552, P = 0.04 for nausea; OR 3.151; 1.213–8.183, P = 0.018 for vomiting) and HEC/MEC (OR 2.321; 1.489–3.617, P < 0.001 for nausea; OR 2.993; 1.245–7.195, P = 0.014 for vomiting) were also significant risks for nausea or vomiting, although A/C chemotherapy was a significant risk for nausea but not for vomiting (OR 4.955; 1.863–13.18, P = 0.001). Our present findings indicating the difference in the cutoff age between nausea and vomiting suggest that the differences in the cutoff age among studies may result from different indices of the control of CINV, including complete response, complete control, and complete protection from nausea or vomiting.
These findings, taken together, suggested that extensive antiemetic medication using other types of antiemetic drugs such as olanzapine in addition to the standard medication is required for prevention of chemotherapy-induced nausea in patients who possess risks for poor control of CINV, including being female, younger age, and A/C chemotherapy.
In the present study, no marked difference in the control of CINV among MEC except for cyclophosphamide-base regimens other than the A/C regimen, although there was a marked difference in the control of CINV among HEC, as mentioned earlier. The low rate of the control of CINV for cyclophosphamide-base regimens may be caused by the patient risks (female and young age) rather than the chemotherapy, because the cyclophosphamide-base regimens were used for the most part in breast cancer patients, whose average age was 48 years.
In conclusion, the control of CINV was investigated in 779 patients receiving 5511 cycles of chemotherapy regimens in our outpatient cancer chemotherapy clinic. In spite of the high rate of adherence to the antiemetic guideline, the control of nausea, but not vomiting, was poor in patients receiving HEC and MEC. A multivariate logistic regression analysis indicated that female gender, age under 60 years, HEC/MEC, and A/C chemotherapy were significant risks for overall nausea. Care should be taken to prevent chemotherapy-induced nausea in high-risk patients.