Immunosuppressive effects of surgery assessed by flow cytometry in nonhuman primates after nephrectomy

Is Early Initiation of Adjuvant Chemotherapy Beneficial for Locally Advanced Rectal Cancer Following Neoadjuvant Chemoradiotherapy and Radical Surgery?

AIM

This study aimed to evaluate whether earlier initiation (< 4 weeks) of adjuvant chemotherapy (ACT) confer any oncological benefits for locally advanced rectal cancer (LARC) patients undergoing neoadjuvant chemoradiotherapy (nCRT) and radical surgery.

METHOD

Clinicopathological and survival outcomes were compared. Propensity score matching (PSM) was performed to adjust for differences between groups. Cox regression analysis was performed to evaluate the impact of earlier ACT initiation on overall survival (OS) and disease-free survival (DFS).

RESULTS

Totally, 443 eligible patients were included. More laparoscopic surgeries, less postoperative complications, and more ACT completion were observed in patients whose ACT was initiated within 4 weeks after surgery (all P < 0.001). With a mean follow-up of 59 months, the 5-year OS and DFS rate was 89.8% and 82.0% in the early group, significantly higher than 81.6% and 73.1% in the late group (P = 0.007, and P = 0.022, respectively). After PSM, the 5-year OS and DFS rate was 90.9% and 84.4% in the early group, significantly higher than 83.4% and 68.8% in the late group (P = 0.047, and P = 0.017, respectively). Cox regression analysis demonstrated that time to ACT initiation (early vs. late, HR = 0.486, P = 0.008) was independently associated with OS.

CONCLUSION

Early initiation of ACT (<4 weeks) confers a survival benefit, and is an independent prognostic factor of OS in LARC patients following nCRT. Further investigations are needed to define the role of earlier initiation of ACT in patients with LARC after nCRT.

Impact of timing of adjuvant chemotherapy on survival in stage III colon cancer: a population-based study

Background

There is no consensus regarding the optimal time to initiate adjuvant chemotherapy after surgery for stage III colon cancer, and the relevant postoperative complications that cause delays in adjuvant chemotherapy are unknown.

Methods

Eligible patients aged ≥66 years who were diagnosed with stage III colon cancer from 1992 to 2008 were identified using the linked Surveillance, Epidemiology, and End Results-Medicare database. Kaplan-Meier analysis and a Cox proportional hazards model were utilized to evaluate the impact of the timing of adjuvant chemotherapy on overall survival (OS).

Results

A total of 18,491 patients were included. Delayed adjuvant chemotherapy was associated with worse OS (9–12 weeks: hazard ratio [HR] = 1.222, 95% confidence interval [CI] = 1.063–1.405; 13–16 weeks: HR = 1.252, 95% CI = 1.041–1.505; ≥ 17 weeks: HR = 1.969, 95% CI = 1.663–2.331). The efficacies of adjuvant chemotherapy within 5–8 weeks and ≤4 weeks were similar (HR = 1.045, 95% CI = 0.921–1.185). Compared with the non-chemotherapy group, chemotherapy initiated at ≥21 weeks did not significantly improve OS (HR = 0.882, 95% CI = 0.763–1.018). Patients with postoperative complications, particularly cardiac arrest, ostomy infection, shock, and septicemia, had a significantly higher risk of a 4- to 11-week delay in adjuvant chemotherapy (p < 0.05).

Conclusions

Adjuvant chemotherapy initiated within 8 weeks was acceptable for patients with stage III colon cancer. Delayed adjuvant chemotherapy after 8 weeks was significantly associated with worse OS. However, adjuvant chemotherapy might still be useful even with a delay of approximately 5 months. Moreover, postoperative complications were significantly associated with delayed adjuvant chemotherapy.

Early versus delayed initiation of adjuvant treatment for pancreatic cancer

Background

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive tumor showing a tendency for early recurrence, even after curative resection. Although adjuvant treatment improves survival, it is unclear whether early adjuvant treatment initiation yields better outcomes in patients with PDAC.

Methods

We retrospectively enrolled 113 patients who underwent chemotherapy or chemoradiotherapy after curative resection of PDAC: Fifty-six and 57 patients were in the early and delayed groups, respectively based on the median time of treatment initiation (35 days [range, 20–83 days]).

Results

Patient baseline characteristics were comparable in both groups, except for grade III or IV postoperative complications (5.4% in the early group vs. 22.8% in the delayed group). With a median 20.3-month follow-up, the overall survival (OS) and disease-free survival (DFS) times were 29.5 and 14.7 months, respectively. The early group had significantly prolonged OS (39.1 vs. 21.1 months, p = 0.018) and DFS (18.8 vs. 10.0 months, p = 0.034), compared to the delayed group. Among 71 patients who completed planned adjuvant treatment, patients in the early group tended to have longer, though not statistically significant, OS and DFS times than those in the delayed group. In 67 patients without postoperative complications, patients in the early group had longer OS (42.8 vs. 20.5 months, p = 0.002) and DFS (19.6 vs. 9.1 months, p = 0.005) than those in the delayed group. By multivariate analysis, incompletion of treatment (hazard ratio [HR]: 4.039, 95% confidence interval [CI]: 2.334–6.992), delayed treatment initiation (HR: 1.822, 95% CI: 1.081–3.070), and positive angiolymphatic invasion (HR: 2.116, 95% CI: 1.160–3.862) were significantly associated with shorter OS.

Conclusions

Adjuvant treatment should be delivered earlier and completed for better outcomes in resected PDAC patients, especially without postoperative complications.

Current practices and challenges of adjuvant chemotherapy in patients with colorectal cancer

Colorectal cancer is one of the most commonly diagnosed cancers in men and women in the developed world. Although surgery is the foundation of curative treatment, adjuvant chemotherapy also improves overall and disease-free survival in high-risk stage II and all stage III patients. Research strongly suggests that the timing from surgery to adjuvant chemotherapy is critical, because delays to the start of treatment significantly affect patient outcomes. Both clinical and systemic barriers, such as postoperative complications and institutional wait times, challenge the timely administration of adjuvant chemotherapy. Further research investigating solutions to overcome these barriers is needed.

Perivascular, but not parenchymal, cerebral engraftment of donor cells after non-myeloablative bone marrow transplantation

Myeloablative (MyA) bone marrow transplantation (BMT) results in robust engraftment of BMT-derived cells in the central nervous system (CNS) and is neuroprotective in diverse experimental models of neurodegenerative diseases of the brain and retina. However, MyA irradiation is associated with significant morbidity and mortality and does not represent a viable therapeutic option for the elderly. Non-myeloablative (NMyA) BMT is less toxic, but it is not known if the therapeutic efficacy observed with MyA BMT is preserved. As a first step to address this important gap in knowledge, we evaluated and compared engraftment characteristics of BMT-derived monocytes/microglia using several clinically relevant NMyA pretransplant conditioning regimens in C57BL/6 mice. These included chemotherapy (fludarabine and cyclophosphamide) with or without 2 Gy irradiation, and 5.5 Gy irradiation alone. Each regimen was followed by transplantation of whole bone marrow from green fluorescent protein-expressing wild type (wt) mice. While stable hematopoietic engraftment occurred, to varying degrees, in all NMyA regimens, only 5.5 Gy irradiation resulted in significant engraftment of BMT-derived cells in the brain, where these cells were exclusively localized to perivascular, leptomeningeal, and related anatomic regions. Engraftment in retina under 5.5 Gy NMyA conditions was significantly reduced compared to MyA, but robust engraftment was identified in the optic nerve. Advancing the therapeutic applications of BMT to neurodegenerative diseases will require identification of the barrier mechanisms that MyA, but not NMyA, BMT is able to overcome.

Irradiation of donor mononuclear cells for treatment of chemorefractory metastatic solid cancers: a community-based immune transplant pilot study

Purpose

Chemotherapy has demonstrated ability to generate tumor antigens secondary to induction of apoptosis, against which human leukocyte antigen-compatible, irradiated, related donor mononuclear cells may be administered with immune stimulation to activate antigen presenting and cytotoxic T cells, while minimizing risk of graft-versus-host disease (GVHD). The present study endeavours to describe feasibility and efficacy of this treatment, specifically in the community setting.

Materials and Methods

Eligible patients had rapidly progressive, chemorefractory metastatic solid tumors. Treatment consisted of intravenous etoposide and cyclosporine for three days followed by granulocyte-macrophage colony-stimulating factor for 5 days. The following week, 5×10⁷ haploidentical or more closely matched irradiated donor mononuclear cells were given weekly for 10 weeks along with interleukin-2.

Results

Three patients were enrolled, and the regimen was well-tolerated, with no GVHD observed. All patients had clinical response, despite advanced and heavily pretreated disease.

Conclusion

The above-outlined protocol demonstrates favorable tolerability and efficacy, and appears to be feasible in the community setting. While the optimal chemotherapy, immunostimulation, and irradiation regimens may be further optimized, future investigation appears warranted, and may include community oncology programs.

Adjuvant chemotherapy for stage III colon cancer: does timing matter?

BACKGROUND

Clinical trials commonly mandate that adjuvant chemotherapy for colon cancer should commence within 8 weeks (56 days) of surgery.

OBJECTIVE

We investigated the consequences of the timing of adjuvant chemotherapy for stage III colon cancer.

PATIENTS AND METHODS

This is a retrospective review of all patients with newly diagnosed stage III colon cancer who received adjuvant chemotherapy in 2 provincial centers in 1999 and 2000. The impact of time to adjuvant chemotherapy on overall survival and relapse-free survival was analyzed by the use of univariate and multivariate Cox modeling, adjusting for prognostic factors.

RESULTS

Three hundred forty-five subjects were included. Median time to adjuvant chemotherapy was 50 days (range, 20-242 days); in 111 (32.2%) patients, it was beyond 56 days. On univariate analysis, time >56 days was nonsignificantly associated with a hazard ratio of death of 1.31 (P = .12). Similar results were seen for relapse-free survival. Planned exploratory analysis suggests that the commencement of adjuvant chemotherapy up to 10 weeks postsurgery still confers a benefit.

CONCLUSIONS

Delaying adjuvant chemotherapy in stage III colon cancer beyond 8 to 10 weeks postsurgery appears to be associated with diminished benefit.

Tweak induces proliferation in renal tubular epithelium: a role in uninephrectomy induced renal hyperplasia

The tumour necrosis factor (TNF) family member TWEAK activates the Fn14 receptor and has pro-apoptotic, proliferative and pro-inflammatory actions that depend on the cell type and the microenvironment. We explored the proliferative actions of TWEAK on cultured tubular cells and in vivo on renal tubules. Additionally, we studied the role of TWEAK in compensatory proliferation following unilateral nephrectomy and in an inflammatory model of acute kidney injury (AKI) induced by a folic acid overdose. TWEAK increased the proliferation, cell number and cyclin D1 expression of cultured tubular cells, in vitro. Exposure to serum increased TWEAK and Fn14 expression and the proliferative response to TWEAK. TWEAK activated the mitogen-activated protein kinases ERK and p38, the phosphatidyl-inositol 3-kinase (PI3K)/Akt pathway and NF-κB. TWEAK-induced proliferation was prevented by inhibitors of these protein kinases and by the NF-κB inhibitor parthenolide. TWEAK-induced tubular cell proliferation as assessed by PCNA and cyclin D1 expression in the kidneys of adult healthy mice in vivo. By contrast, TWEAK knock-out mice displayed lower tubular cell proliferation in the remnant kidney following unilateral nephrectomy, a non-inflammatory model. This is consistent with TWEAK-induced proliferation on cultured tubular cells in the absence of inflammatory cytokines. Consistent with our previously published data, in the presence of inflammatory cytokines TWEAK promoted apoptosis, not proliferation, of cultured tubular cells. In this regard, TWEAK knock-out mice with AKI displayed less tubular apoptosis and proliferation, as well as improved renal function. In conclusion, TWEAK actions in tubular cells are context dependent. In a non-inflammatory milieu TWEAK induces proliferation of tubular epithelium. This may be relevant for compensatory renal hyperplasia following nephrectomy.

Cancer: A medical emergency

Over the last decade clinical trials have established the effectiveness of adjuvant chemotherapy in eradicating micrometastases in many different cancers, including breast, colon, and lung. This success stands in sharp contrast to our failure to cure clinically evident metastatic cancer. These dramatic polarities illustrate the critical importance of treatment timing if residual cancer is to be eradicated. Adjuvant chemotherapy is started only after recovery from surgery, a period of time that can exceed 30 days. During this time any cancer that remains after surgery will continue to divide. Although adjuvant chemotherapy has proven effective despite this time delay, there are reasons, both conceptual and quantitative, to think that its effectiveness could be magnified by a more prompt administration. The extent of this magnification is mathematically modeled in this paper. Surgery and the process of wound healing after surgery create a very favorable environment for the growth of the metastatic clone. Surgery can increase the number of circulating tumor cells and induce an immunosuppressive effect that might facilitate metastatic spread. And the process of wound healing can stimulate growth factors that have been shown to accelerate tumor cell growth. This situation is a double-edged sword. Although the metastatic clone should proliferate rapidly during this time, it should also, at least theoretically, be more sensitive to the effects of chemotherapy as more cells are pushed into a cycling phase. We derive a mathematical model based upon empirical data predicting that the effectiveness of a given chemotherapeutic regimen is inversely proportional to the tumor burden that has to be eradicated, which, in turn, is a function of when chemotherapy is started after surgery. Although the critical importance of timing in the treatment of cancer is intuitive, this knowledge has not yet been fully translated into the clinical practice of medical oncology. If the model presented is accurate, many people are dying unnecessarily of their cancer today because we are waiting too long after surgery to use highly effective chemotherapies, following well-trod clinical paths and established paradigms for how cancer should be treated.