Palliation of colorectal cancer

Synthesis and characterisation of a nucleotide based pro-drug formulated with a peptide into a nano-chemotherapy for colorectal cancer

Recent studies in colorectal cancer patients (CRC) have shown that increased resistance to thymidylate synthase (TS) inhibitors such as 5-fluorouracil (5-FU), reduce the efficacy of standard of care (SoC) treatment regimens. The nucleotide pool cleanser dUTPase is highly expressed in CRC and is an attractive target for potentiating anticancer activity of chemotherapy. The purpose of the current work was to investigate the activity of P1, P4-di(2',5'-dideoxy-5'-selenouridinyl)-tetraphosphate (P4-SedU2), a selenium-modified symmetrically capped dinucleoside with prodrug capabilities that is specifically activated by dUTPase. Using mechanochemistry, P4-SedU2 and the corresponding selenothymidine analogue P4-SeT2 were prepared with a yield of 19% and 30% respectively. The phosphate functionality facilitated complexation with the amphipathic cell-penetrating peptide RALA to produce nanoparticles (NPs). These NPs were designed to deliver P4-SedU2 intracellularly and thereby maximise in vivo activity. The NPs demonstrated effective anti-cancer activity and selectivity in the HCT116 CRC cell line, a cell line that overexpresses dUTPase; compared to HT29 CRC cells and NCTC-929 fibroblast cells which have reduced levels of dUTPase expression. In vivo studies in BALB/c SCID mice revealed no significant toxicity with respect to weight or organ histology. Pharmacokinetic analysis of blood serum showed that RALA facilitates effective delivery and rapid internalisation into surrounding tissues with NPs eliciting lower plasma Cmax than the equivalent injection of free P4-SedU2, translating the in vitro findings. Tumour growth delay studies have demonstrated significant inhibition of growth dynamics with the tumour doubling time extended by >2weeks. These studies demonstrate the functionality and action of a new pro-drug nucleotide for CRC.

Palliative surgical outcome score (PSOS) in patients treated palliatively with self-expanding metal stent (SEMS) for malignant incurable colorectal obstruction

AIM

The palliative surgical outcome score (PSOS) was proposed for evaluation of the effect of palliative surgical interventions. As a surrogate measure for successful symptom control, it is defined as the proportion of days outside the hospital of the remaining life time up to six months after a palliative intervention. In this study we evaluate the PSOS in patients treated palliatively with self-expanding metal stents (SEMSs) for incurable malignant colorectal obstruction.

METHODS

All eligible patients endoscopically treated with palliative intent with SEMSs were identified. Demographics and clinical characteristics, including complete follow-up, were recorded, and the PSOS was calculated. Non-parametric tests were used for comparisons, and survival was evaluated by univariable and multivariable analyses.

RESULTS

Between 2005 and 2013, 116 patients (median age 71.5 years; 53.4% women) were identified. Most obstructions were caused by primary colorectal cancers. Technical- and clinical success rates were 94.0% and 87.1%, respectively. Procedure-related complications occurred in 17 (14.7%) of the patients, and most were minor. A PSOS>70 (regarded as excellent palliation) was achieved in 79 (68.1%) patients. This goal was significantly more often achieved in patients who survived at least 6 months than in those with shorter survival (p < 0.001). No clinical variables at the time of the endoscopic palliative procedure could predict a PSOS>70. However, in patients who survived at least 6 months (n = 69), a PSOS>70 was independently associated with better survival in the multivariable Cox analysis.

CONCLUSIONS

PSOS could be used as a practical proxy or a pragmatic tool for the effectiveness of palliative interventions, when such interventions are compared. Clinical factors that could significantly add to the clinical decision-making and predict a PSOS>70 in an individual patient were not identified for this specific group of patients.

A novel approach to inoperable or recurrent rectal cancer by chemoembolization: A new arrow in our quiver?

Purpose

Assess the feasibility, safety and efficacy of TACE with irinotecan loaded micro particles (debiri) for the treatment of locally advanced rectal cancer patients.

Results

We assessed the Edmonton Symptom Assessment System (ESAS). The tool is designed to assess nine common symptoms in cancer patients: pain, tiredness, nausea, depression, anxiety, drowsiness, appetite, wellbeing and shortness of breath. The ESAS score was 7 in 10/12 (83%) patients before treatment and 6 in 2/12 (16.5%) patients. After treatment in 6/12 (50%) patients the score dropped to 3; 3/12 (33%) reported 4, 1/12 (8%) reported 2. All patients experienced local control disease with a degree of citoreduction; in 4 cases (33%) we observed outstanding responses with a dramatic reduction in the tumors size which led us to surgical radical resections.

Materials and methods

We run a prospective mono-institutional study where we recruited, 12 non- consecutive patients with histology confirmation of rectal cancer, inoperable and not treatable due to severe comorbidities, or pelvic recurrence/progression after curative treatment, chemotherapy, radiotherapy and/or surgery. Their performance status (PS) ECOG was 2-3. Twelve patients (10 male and 2 female) with a median age 71 (range 56-89) were recruited in the study.

Conclusions

The study has met the primary endpoint and showed encouraging activity. Debiri could be a possible option for locally advanced/inoperable or recurred rectal cancer patients. Further trials are warranted to validate this methodic in early stages.

Exploring Different Strategies for Efficient Delivery of Colorectal Cancer Therapy

Colorectal cancer (CRC) is the third most common cancer and the fourth leading cause of cancer death in the world. Currently available chemotherapy of CRC usually delivers the drug to both normal as well as cancerous tissues, thus leading to numerous undesirable effects. Much emphasis is being laid on the development of effective drug delivery systems for achieving selective delivery of the active moiety at the anticipated site of action with minimized unwanted side effects. Researchers have employed various techniques (dependent on pH, time, pressure and/or bacteria) for targeting drugs directly to the colonic region. On the other hand, systemic drug delivery strategies to specific molecular targets (such as FGFR, EGFR, CD44, EpCAM, CA IX, PPARγ and COX-2) overexpressed by cancerous cells have also been shown to be effective. This review aims to put forth an overview of drug delivery technologies that have been, and may be developed, for the treatment of CRC.

Inferior mesenteric artery chemoembolization and chemotherapy for advanced rectal cancer: report of a clinical case

Patients with advanced and incurable colorectal cancer have a very poor prognosis. Curative-intent resection was performed in 70%-90% of cases in reported series of colorectal cancer, sometimes after neoadjuvant chemotherapy and radiotherapy. The remaining 10%-30% of patients are treated with palliative intent, where treatment is aimed at relieving disease-related symptoms and improving quality of life. The provision of palliative care for these patients is complicated and outcomes are often disappointing. Although there are many available options including a variety of surgical and nonsurgical interventions, the best management remains controversial. Transarterial chemoembolization with irinotecan-loaded drug-eluting beads (DEBIRI) is an effective, minimally invasive procedure performed by interventional radiologists that allows intra-arterial drug delivery to stop vascular feeding and exert local cytotoxic effects. We here report on a patient treated with DEBIRI followed by systemic chemotherapy with the FOLFOX regimen for locally advanced, inoperable colorectal cancer.

Use of the comet assay technique for quick and reliable prediction of in vitro response to chemotherapeutics in breast and colon cancer

Background

Determination of response to chemotherapy is a major requirement of personalized medicine. Resistance, whether developed or native, critically affects a treatment’s success. Single Cell Gel lectrophoresis - also known as a comet assay - is used to detect DNA damage at the level of individual eukaryotic cells. We assessed the use of comet assays in determining response to chemotherapeutic drugs that are widely used in breast and colon cancer.

Results

We treated human breast and colon cancer cell lines with melphalan, cisplatin, mechlorethamine or doxorubicin, as monotherapies. Drug activities varied even in the same cancer types, further demonstrating the heterogeneity of different cancer types.

Conclusion

The comet assay technique can provide reliable and quick results with minimum requirements and is applicable to a wide variety of drugs.

Efficacy of ex vivo activated and expanded natural killer cells and T lymphocytes for colorectal cancer patients

Immune cell-based therapies using natural killer (NK) cells and cytotoxic T cells are under constant scrutiny, with the aim to design an effective and reduced-toxicity therapy, which will benefit patients via improved quality of life and improved prognosis. Four patients with stage IV colon cancer were administered 1, 3, 5 and 6 effector cell intravenous infusions, respectively. Peripheral blood was collected from the patients and the ex vivo activation and expansion of NK and T cells was performed in Good Manufacturing Practice-certified clean rooms for ~12-15 days. Immunophenotypic analysis of the peripheral blood mononuclear cells (PBMCs) and expanded NK and T cells was conducted using flow cytometry and the patients were followed up. On average, 4.8×10⁷ initial PBMCs and 2.7×10⁹ total expanded cells were obtained. The intravenous infusions of the expanded cells were not accompanied by adverse reactions. Improved prognosis, reflected by a considerable decrease in the cancer markers, accompanied by an improved quality of life in the patients were observed. In conclusion, potential strategies are currently under development for the large-scale production of effectors cells; therefore, autologous immune enhancement therapy (AIET) may be considered as a viable approach to cancer treatment.

Palliative surgery in patients with unresectable colorectal liver metastases: a propensity score matching analysis

BACKGROUND AND OBJECTIVES

The current study was primarily intended to determine the best surgical treatment for patients with unresectable liver metastatic colorectal cancer (CRC). In addition, we assessed whether the improvement in survival resulting from palliative resection (PR) of the primary tumor was a function of the extent of liver metastasis.

METHODS

The demographics, tumor characteristics, and survival outcomes of 261 patients who underwent palliative surgery for unresectable liver metastatic CRC were analyzed. A propensity-score model was used to compare the group of patients receiving PR and non-resection (NR).

RESULTS

There were 195 PR patients and 66 NR. The median survival of PR and NR patients was 21 months and 10 months, respectively (P < 0.001). In a Cox multivariate analysis of 51 propensity-score matched pairs, PR resulted in longer survival than NR (Hazard Ratio for NR 1.481; 95% confidence interval: 1.003-2.185; P = 0.048). The extent of liver metastasis only led to better survival of PR than NR patients among patients with limited liver metastasis not among those with extensive liver metastasis (P = 0.001).

CONCLUSIONS

PR appears to result in better survival than NR when the patient's overall condition permits an aggressive approach, especially in patients with limited liver metastases.

Management of stage IV rectal cancer: Palliative options

Approximately 30% of patients with rectal cancer present with metastatic disease. Many of these patients have symptoms of bleeding or obstruction. Several treatment options are available to deal with the various complications that may afflict these patients. Endorectal stenting, laser ablation, and operative resection are a few of the options available to the patient with a malignant large bowel obstruction. A thorough understanding of treatment options will ensure the patient is offered the most effective therapy with the least amount of associated morbidity. In this review, we describe various options for palliation of symptoms in patients with metastatic rectal cancer. Additionally, we briefly discuss treatment for asymptomatic patients with metastatic disease.