Oral tegafur/uracil

Unexpected effect of halogenation on the water solubility of small organic compounds

Halogenation is an indispensable method in the structural modification of lead compounds. It is known to increase lipophilicity and is hence used to improve membrane permeability and thus bioavailability. In this study, we compare the water solubility (logS) of organohalogen compounds and their non-halogenated parent compounds using the molecular matched pair (MMP) analysis method. Unexpectedly, 19.9% of the compounds increased their water solubility upon halogenation. Iodination was observed to have the greatest effect on solubility, followed by chlorination, bromination, and fluorination. Introducing amino, hydroxyl and carboxyl groups into organohalogens improves their aqueous solubilities, whereas introducing a trifluoromethyl group has the opposite effect. According to our quantum chemical calculations, the increased water solubility upon halogenation is, at least partially, attributed to an increased polarity and polarizability. These results improve our understanding of the influence of halogenation on bioactivity.

The Overall Efficacy and Outcomes of Metronomic Tegafur-Uracil Chemotherapy on Locally Advanced Head and Neck Squamous Cell Carcinoma: A Real-World Cohort Experience

Simple Summary

In head and neck squamous cell carcinoma (HNSCC), more than 60% of patients presenting with locally advanced disease carries a high risk of recurrence and distant metastasis, with a poor prognosis (five-year overall survival (OS), <50%). Therefore, further prevention of recurrence and distant metastasis is crucial for survival improvement in advanced HNSCC patients. In this retrospective study, we investigated the outcomes of metronomic chemotherapy with tegafur–uracil in locally advanced HNSCC (LA HNSCC). Our data showed that adding tegafur–uracil after curative surgery with adjuvant chemoradiotherapy or definitive concurrent chemoradiotherapy significantly improved OS, DFS, and DMFS in patients with LA HNSCC. As a metronomic maintenance regimen, tegafur–uracil was well tolerated with minimal adverse effects. We suggested tegafur–uracil as a maintenance therapy of choice for patients with LA HNSCC.

Abstract

Metronomic chemotherapy inhibits tumor growth by continuous administration of lower-dose chemotherapy. Our study aimed to demonstrate the outcomes of metronomic chemotherapy with tegafur–uracil in locally advanced head and neck squamous cell carcinoma (LA HNSCC). This was a retrospective study including 240 patients with LA HNSCC. After standard treatment, 96 patients were further treated with metronomic tegafur-uracil, and 144 patients were not. No statistical differences were found between both groups with regard to sex, clinical stage, or primary treatment choice. There were more hypopharyngeal cancers and more patients with poor clinicopathological features, including lymphovascular invasion, extranodal extension, and positive margins in the tegafur–uracil group. The median follow-up duration was 31.16 months. Overall survival (OS) was not reached in the tegafur–uracil group and was 54.1 months in the control group (p = 0.008). The median disease-free survival (DFS) was 54.5 months in the tegafur–uracil group and 34.4 months in the control group (p = 0.03). Neither group reached distant metastasis-free survival (DMFS, p = 0.02). In patients with LA HNSCC, adding tegafur–uracil as metronomic chemotherapy after either curative surgery with adjuvant chemoradiotherapy or definitive concurrent chemoradiotherapy significantly improved the OS, DFS, and DMFS with tolerable adverse events.

Treatment of stage IV colorectal carcinoma in elderly patients

Colorectal adenocarcinoma ranks second as a cause of death due to cancer in the Western world. In Europe, 40% of patients with colorectal cancer are over 70 years old and the incidence increased through the 1980's. Without any treatment the median survival after the detection of liver metastases is approximately 9 months, depending on the extent of disease at the time of diagnosis but not on the patients age. In the elderly there are only few data apt to define the standard regimen in the advanced disease, but results seem similar to those observed in younger patients. As a result of exclusion criteria and screening, elderly patients entering clinical trials are usually a select group, with good performance status, access to transportation, and limiting numbers of coexisting conditions. This paper examines the factors pertinent to the small number of clinical trials designed for metastatic colorectal cancer in this group of persons.

Colorectal cancer in the elderly: is palliative chemotherapy of value?

Colorectal cancer is a disease of the elderly, with 70% of patients being aged 65 years or older. In Western countries, the total number of elderly patients with this disease is expected to further increase in the future. Since the incidence of adverse physical or socioeconomic conditions in the elderly is higher than in younger patients, a thorough assessment of the patient's suitability for therapy should be performed before a decision is made. Using a Comprehensive Geriatric Assessment (CGA) to subdivide the population of elderly cancer patients into three groups can help to guide treatment decisions. Both in the adjuvant and in the palliative setting, there are sufficient data supporting the use of fluorouracil-based chemotherapy in fit elderly patients who can tolerate cytotoxic treatment. Systemic chemotherapy has been shown to effectively reduce mortality in the adjuvant situation and to be of clinical benefit for patients with metastatic disease in terms of longer survival, control of symptoms and quality of life. In recent years, new substances such as oxaliplatin or irinotecan have shown significant activity in the treatment of patients with metastatic colorectal cancer. However, information on how to guide the use of these new drugs in elderly patients is still lacking. Limited data from clinical trials indicate treatment efficacy in selected elderly patients comparable to that observed in younger patients, with overall manageable toxicity. Clearly, further clinical trials in elderly patients with colorectal cancer are necessary as well as the incorporation of aspects of geriatric medicine into the teaching programme of medical oncologists.

Systemic therapy for colorectal cancer

Colorectal cancer alone accounts for around 200,000 deaths in Europe and represents a significant health problem. Although about fifty percent of patients are cured by surgery alone, the other half will eventually die due to metastatic disease, which includes approximately 25% of patients who have evidence of metastases at the time of diagnosis. Surgical resection of the primary tumor and regional lymph nodes is the only curative therapy for colorectal cancer. However, adjuvant chemotherapy in stage III for colon cancer following curative resection has been shown to reduce the risk of recurrence by 19-40% and of death by 16-33%. Today, 5-fluoroUracil and Leucovorin given for six months may represent the best adjuvant treatment available The contribution of levamisole to adjuvant treatment seems to be marginal, if any. The benefit of adjuvant chemotherapy for the patients with Dukes B colon cancer is less clear. A meta-analysis of 1,381 patients with advanced colorectal cancer showed a significant increase in response rate with the bolus 5-fluoroUracil and Leucovorin versus 5-fluoroUracil alone but no significant difference in median survival. Continuous infusion allows higher doses of 5-FU than rapid bolus infusion and improves response rate survival and time to progression. Oral fluoropyrimidines (capecitabine and Uracil/Tegafur [UFT]) are as active as intravenous fluoropyrimidines. Compared to intravenous 5FU, oral fluoropyrimidines have safety advantages clinical benefits, and are more convenient for patients. Phase III randomized clinical trials in patients with metastatic colorectal cancer demonstrate the significant superiority of combining irinotecan with 5-fluoroUracil and Leucovorin or oxaliplatin with 5-fluoroUracil and Leucovorin over the same 5-fluoroUracil and Leucovorin alone. Several phase II studies have shown that the combination of the oral fluoropyrimidines plus irinotecan or oxaliplatin is very active in metastatic colorectal cancer. Trials with agents acting on novel targets in colorectal cancer are progressing rapidly, including doxifluridine, new inhibitors of thymidylate synthase (ZD9331), oral camptothecins (Rubitecan), multitarget antifolate antimetabolite (Premetrexet), inhibitors of epidermal growth factor receptor (Cetuximab), COX-2 inhibitors (celecoxib) and farnesyltransferaze inhibitors (Zarnestra). However, a few randomized trials failed to show a survival advantage compared with placebo in patients with advanced refractory colorectal cancer.