Bevacizumab Combined with S-1 and Raltitrexed for Patients with Metastatic Colorectal Cancer Refractory to Standard Therapies: A Phase II Study

LESSONS LEARNED

Bevacizumab combined with S-1 and raltitrexed demonstrated positive antitumor efficacy and acceptable toxicity. This combination might represent a treatment option for refractory metastatic colorectal cancer.

BACKGROUND

In patients with metastatic colorectal cancer (mCRC) refractory to standard therapies, S-1 plus raltitrexed showed a good objective response rate (ORR) and significant survival benefit in our previous study. In the present study, we assessed the activity and safety of bevacizumab combined with S-1 and raltitrexed.

METHODS

This investigator-initiated, open-label, single-arm, phase II trial was performed at West China Hospital in China. Patients with mCRC who had disease progression after fluoropyrimidine, irinotecan, and oxaliplatin and had at least one measurable lesion were eligible for this trial. Anti-epidermal growth factor receptor (EGFR) (for tumors with wild-type RAS) and anti-vascular endothelial growth factor (VEGF) therapy in the first or second line was allowed, but patients who had been treated with bevacizumab across two consecutive chemotherapy regimens were excluded. Patients received bevacizumab (7.5 mg/kg on day 1), oral S-1 (80-120 mg per day for 14 days), and raltitrexed (3 mg/m² on day 1) every 3 weeks. The primary endpoint was ORR. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and toxicity.

RESULTS

From September 2015 to November 2019, 44 patients were enrolled. Tumor response evaluation was available in 44 patients at the time of the analysis. There were no complete responses; the ORR was 15.9%, and the disease control rate was 54.5%. Median PFS and OS were 110 days (95% confidence interval [CI], 65.0-155.0) and 367 days (95% CI, 310.4-423.6), respectively. The combination was well tolerated.

CONCLUSION

Bevacizumab combined with S-1 and raltitrexed showed promising antitumor activity and safety in refractory mCRC.

Chemoradiotherapy Is Inferior to Chemotherapy Alone in Adjuvant Setting for Signet Ring Cell Containing Gastric Cancer

Background

Signet ring cell containing gastric cancer (SRCGC) is a rare subtype of gastric cancer, and its adjuvant therapy is based on general gastric cancer. However, the effectiveness of radiotherapy for those SRCGC patients remains unknown.

Purpose

The purpose of the study was to analyze whether the addition of radiotherapy to adjuvant chemotherapy (CT) can benefit survival in resected SRCGC patients.

Methods

Patients with SRCGC, who underwent D2 gastrectomy followed by adjuvant chemotherapy or chemoradiotherapy (CRT), were retrospectively collected. According to the proportion of signet ring cells, patients were histologically classified as pure SRCGC (pSRCGC) containing 100% of signet ring cells, mixed SRCGC (mSRCGC) containing >50% of signet ring cells, and contaminated SRCGC (cSRCGC) containing <50% of signet ring cells. Among the 272 patients, 156 were treated by CT alone and 116 by CRT. The primary endpoint was 3-year overall survival rate (3-year OS rate).

Results

With a median follow-up of 80.5 months, the 3-year OS rate was significantly higher in the CT group (70.5% vs. 58.6%, HR = 0.633, P = 0.017) compared with CRT group. Three independent characteristics were predictive of a poor overall survival: CRT treatment (P = 0.019), tumor size ≥5 cm (P < 0.001), and the presence of vessel invasion (P = 0.009). Subgroup analyses showed CRT significantly impaired prognosis in SRCGC patients in the cSRCGC subset, as well as lesions located in lower-middle sites, subtotal gastrectomy, male, <60 year, and no vessel invasion. Peritoneal was the most common recurrence site in SRCGC patients. The adverse events leukopenia and neutropenia were more common in the CRT group (P = 0.007).

Conclusions

Adjuvant chemoradiotherapy was associated with poor survival compared with adjuvant chemotherapy in SRCGC patients with D2 gastrectomy.

S-1 plus Raltitrexed for Refractory Metastatic Colorectal Cancer: A Phase II Trial

Lessons Learned.

The upregulation of dihydropyrimidine dehydrogenase (DPD) and thymidylate synthase (TS) are important mechanisms of resistance to 5‐fluorouracil (5‐FU) in metastatic colorectal cancer (mCRC) after long exposure to 5‐FU.

S‐1 (containing a DPD inhibitor) combined with raltitrexed (a TS inhibitor) showed a moderate effect, which needs further study as a third‐ or later‐line therapy in mCRC.

Background.

5‐fluorouracil (5‐FU) is a fundamental drug in the treatment of metastatic colorectal cancer (mCRC). Patients with mCRC are often exposed to 5‐FU and/or its analogues for a long time because of its central role in treatment regimens. The upregulation of dihydropyrimidine dehydrogenase (DPD) and/or thymidylate synthase (TS) are important mechanisms of resistance of 5‐FU. To evaluate the efficacy and safety of S‐1 (containing a DPD inhibitor) and raltitrexed (a TS inhibitor) for refractory mCRC, a one‐center, single‐arm, prospective phase II trial was conducted.

Methods.

Patients who had mCRC that had progressed after treatment with fluoropyrimidine, irinotecan, and oxaliplatin and who had at least one measurable lesion were eligible for this trial. Patients received oral S‐1 (80–120 mg for 14 days every 3 weeks) plus an intravenous infusion of raltitrexed (3 mg/m² on day 1 every 3 weeks). The primary endpoint was objective response rate (ORR). Secondary endpoints included progression‐free survival (PFS), overall survival (OS), and toxicity.

Results.

In total, 46 patients were enrolled. Three patients did not complete the first assessment because of adverse events and unwillingness, leaving tumor response evaluation available in 43 patients. Of 43 evaluable patients, the ORR was 13.9% and disease control rate was 58.1%. In the intention‐to‐treat population (n = 46), the ORR was 13.0% and disease control rate was 54.3%. Median PFS and median OS were 107 days (95% confidence interval [CI], 96.3–117.7) and 373 days (95% CI, 226.2–519.8), respectively. Most of the adverse effects were mild to moderate.

Conclusion.

S‐1 combined with raltitrexed for refractory mCRC showed moderate effect, and it is worthy of further study as third‐ or later‐line therapy in mCRC.

Association between single nucleotide polymorphisms in AKT1 and the risk of prostate cancer in the Chinese Han population

AKT1, also known as v-akt murine thymoma viral oncogene homolog 1, is involved in the regulation of cell-survival and anti-apoptotic activities, which may affect the pathogenesis of various cancers. However, the association between genetic variants of AKT1 and the risk of developing prostate cancer has not been investigated before. This study investigated the associations between three polymorphisms (rs1130214, rs3730358, and rs2494732) in AKT1 and the risk of development of prostate cancer in the Chinese Han population. Sequenom MassARRAY & iPLEX technology were used to genotype these polymorphisms in 493 Chinese Han patients with prostate cancer and 309 age-matched healthy individuals. Compared to the CC genotype of the rs3730358 polymorphism, the CT genotype of the same polymorphism was strongly associated with a decreased risk of prostate cancer (OR = 0.617, 95%CI = 0.390-0.976, P = 0.037). However, there was no significant difference between the allele frequency of the rs3730358 polymorphism and those of the other two polymorphisms (P > 0.05). Moreover, no significant difference was found in the haplotype analysis (P > 0.05). Our study found that the variant genotype CT of rs3730358 of AKT1 was associated with a decreased risk of prostate cancer, which suggested that this polymorphism could play an important role in the development of the disease.

Clinical significance of serum CA125 in diffuse malignant mesothelioma

Background

Malignant mesothelioma (MM) is a rare and fatal neoplasm. For diffuse malignant mesothelioma (DMM) patients that were not suitable for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy, systemic chemotherapy is the main treatment. There are no convenient tumor markers to predict the efficacy of treatment and disease progression. This study aimed to evaluate serum CA125 level as a biochemical marker of response to therapy and prognosis in patients with DMM.

Methods

A retrospective study was performed in a single medical institution from April 2008 to April 2014. Overall survival (OS) and prognostic factors were assessed.

Results

Forty-one patients were included with a median age of 53 years. The median OS of all patients was 10 months. Patients with baseline CA125 > 280 U/ml had worse OS compared with the patients that baseline CA125 ≤ 280 U/ml. Baseline level of CA125, stage of disease, primary tumor location and systemic chemotherapy were independent prognostic factors associated with OS. In patients who received systemic chemotherapy, the decline in serum CA125 was associated with favorable OS and objective response according to modified Response Evaluation Criteria in Solid Tumors criteria.

Conclusions

The baseline level of serum CA125, accompanied with stage of disease, primary tumor location and systemic chemotherapy, could be regarded as independent prognostic factors for DMM patients. Otherwise, the change in serum CA125 can predict OS and response to systemic chemotherapy.

Phase II study of oxaliplatin combined with S-1 and leucovorin (SOL) for Chinese patients with metastatic colorectal cancer

BACKGROUND

Fluoropyrimidine and oxaliplatin are widely used for patients with colorectal cancer. This phase II study was conducted to evaluate the efficacy and safety of the combination of S-1, oxaliplatin, and leucovorin (SOL) in the treatment of Chinese patients with metastatic colorectal cancer (mCRC).

METHODS

Eligible patients with untreated mCRC from four hospitals in China received intravenous oxaliplatin (85 mg/m(2)) on day 1, oral S-1 twice daily (80-120 mg per day) on day 1-7, and leucovorin twice daily (50 mg per day) simultaneously with S-1, every 2 weeks.

RESULTS AND DISCUSSION

Forty patients were enrolled in our study. In total, 296 cycles of SOL were administered. The overall response rate was 50.0%. At a median follow-up of 27 months, progression-free survival and overall survival were 7.0 months (95% confidence interval [CI] 6.0-10.6 months) and 22.2 months (95% CI 15.1-29.3 months), respectively. The most common grade 3/4 non-hematological adverse events were diarrhea (n = 8, 20.0%), nausea (n = 3, 7.5%), and vomiting (n = 3, 7.5%). The most common grade 3/4 hematological toxicities were thrombocytopenia (n = 3, 7.5%), neutropenia (n = 1, 2.5%), and abnormal alanine transaminase/aspartate transaminase levels (n = 1, 2.5%). There was one treatment-related death.

CONCLUSIONS

The data indicate that the SOL regimen is effective and moderately tolerated in Chinese patients with mCRC.

TRIAL REGISTRATION

CLINICAL TRIAL INFORMATION

ChiCTR-TNRC-100000838.

[Relationship between expression of Cat V and clinicopathologic character of myasthenia gravis in patients with thymoma]

OBJECTIVE

To investigate the association of expression of Cat V with the clinicopathologic variables of myasthenia gravis (MG) in patients with thymoma.

METHODS

Seventy-eight patients with thymomas were involved. Immunohistochemical method was adopted in investigating the protein expression of Cat V in the thymomas and thymic tissues adjacent to thymomas.

RESULTS

The protein of Cat V could be detected in both thymomas and thymic tissues. And the cortex was the main expressive domain of Cat V in thymus. The positive ratio of Cat V expression in thymoma was significantly increased in patients with MG, compared with that in patients without MG (82.50% vs 26.33%, P < 0.01), and similar results were observed in thymic tissues adjacent to tumors (77.50% vs 31.58%, P < 0.01). Analysis on the relationship of the clinical subtypes of MG with expression of Cat V revealed that the positive ratio in type II (92.00%) and type III (83.33%) was much higher than that in type I (55.56%) (P < 0.05). The expression of Cat V was significantly raised in the epithelial-rich and mixed cell thymomas when compared with that in the lymphocyte-rich ones. No statistically significant difference was found on the variables such as perioperative myasthenic crisis, sex or age of patient, duraton of sickness and expression of Cat V.

CONCLUSION

The overexpression of Cat V in thymomas may be associated with MG.

[Histopathological study of subcutaneous heterograft of human gastric cancer in nude mice treated with 211At labelled monoclonal antibody]

The histopathological changes of subcutaneous heterograft of human gastric cancer in nude mice were examined 5-10 days after intravenous injection of a single dose of 211At labelled McAb(211At-3H11). The results showed that there was a relatively selective localization and therapeutic effect as biomissile, which led to a radiation response of gastric cancer cells (GCCs) and decreased the mitosis of GCCs with a dose-response correlation among the 8, 16, and 24 microCi 211At-3H11 groups. The effectiveness of a single dose of 211At-3H11 injected intravenously in the tumor bearing nude mice lasted not longer than 5-6 days, meanwhile in the mice exposed to the dosage of 16 or 24 microCi, mitosis in GCCs disappeared, and at the same time there was no obvious repair or regeneration of GCCs.

[Inhibitory effect of refined Amorphophallus konjac on MNNG-induced lung cancers in mice]

550 seven-wk-old LACA mice were used in 3 batches for studying the inhibitory effect of refined Amorphophallus konjac (Konjaku powder) on MNNG-induced lung cancers. The mice (within each batch) were randomly allocated into four groups, namely, positive control (MNNG), Amorphophallus konjac (A. K.), complex (MNNG+A. K.), and blank control (C) groups. In MNNG group, MNNG (250 micrograms) was injected intravenously once every five days for seven times in each mouse, the total dosage of MNNG being 1.75 mg. In A. K. group, according to w/w, 8% A. K. was well mixed into 92% common diet for long-term breeding. In the complex group, MNNG was given as that in MNNG group and the mice were kept as those in A. K. group. The mice in MNNG group and in C group were all maintained on common diet. The results showed different degrees of inhibitory and preventive effect of refined A. K. on MNNG-induced lung cancers. Refined A. K. not only exerted effect on the number of induced cancer and precancerous lesions, causing a drop in cancer rate from 70.87% to 19.38% and the mean number of cancer and precancerous lesions in each animal, but also altered the constituent ratio of the kinds of tumors, showing a decrease in malignancy (adenoma with malignant change), absence of adenocarcinoma, and relative increase in benign adenoma. The results of experiments in 3 batches also exhibited good reproducibility as well as absence of adverse reaction to Konjaku powder.

[Study on carcinogenic activity of several nickel compounds in mice]

This paper reports the result of the tumor in site induced by several nickel compounds in mice. Three nickel compounds (Ni3S2, NiCl, pure nickel powder) were injected separately to the right arm pit subcutaneously (5 mg/mouse). At the end of the 62nd week, the tested mice were sacrificed. Only nickel sulfide induced tumors in the site of injection, the incidence of tumor was 36%. The majority of the tumors were fibrosarcomas, only 2 rhabdomyosarcomas. The tumors might infiltrate into the surrounding tissues, a few metastasized to the liver and/or the lungs.