Sustained Disease Control in Immune Checkpoint Blockade Responders with Microsatellite Instability-high Colorectal Cancer after Treatment Termination.

Immune checkpoint inhibitors improve survival in patients with mismatch repair deficiency/microsatellite instability-high (MSI-H) colorectal cancer. The recurrence outcomes following discontinuation of immunotherapy after prolonged disease control have not been definitively reported in large series. Records from patients with advanced MSI-H colorectal cancer from The University of Texas - MD Anderson Cancer Center who received immunotherapy between 2014 and 2022 and stopped after prolonged clinical benefit were reviewed. Median progression-free and overall survival were estimated. Associations between the event of recurrence and coexisting mutations (KRAS/NRAS, BRAFV600E), metastatic organ involvement (lung, liver, lymph node, or peritoneum), metastatic timing (synchronous vs. metachronous), prior immunotherapy [anti-PD-(L)1 alone or in combination with anti-CTLA antibodies], etiology of MSI status (sporadic vs. hereditary non-polyposis colorectal cancer), and duration of immunotherapy were assessed. Sixty-four patients with MSI-H colorectal cancer without progression on immunotherapy were reviewed. Of these 48 and 16 received anti-PD(L)1 antibody alone or in combination with anti-CTLA-4 antibody, respectively. Median exposure to immunotherapy was 17.6 months (range, 1.3-51.9). After a median follow-up of 22.6 months (range, 0.3-71.7) after stopping immunotherapy, 56 of 64 patients (88%) remained without disease progression. Lung metastases were associated with recurrence/progression (OR, 6.1; P = 0.04), but coexisting mutation, primary tumor sidedness, and immunotherapy were not. These data provide a retrospective, single-institution analysis that showed that most patients with advanced MSI-H colorectal cancer do not recur after treatment cessation, regardless of the reason for stopping treatment or a variety of patient and disease features, supporting an optimistic prognosis of sustained disease control. SIGNIFICANCE: Outcomes for patients with MSI-H colorectal cancer stopping immunotherapy after disease control remain unknown. Sixty-four patients with MSI-H colorectal cancer from our institution stopping treatment for sustained benefit or toxicity were retrospectively assessed. After median follow up of 22 months and median immunotherapy exposure of 18 months, 88% patients remained without progression. All patients who recurred or progressed and were rechallenged with immunotherapy have continued to experience disease control.

Taxane-Based Chemotherapy Is Effective in Metastatic Appendiceal Adenocarcinoma.

Appendiceal cancer is a rare, orphan disease with no therapies currently approved by the FDA for its treatment. Given the limited data regarding drug efficacy, these tumors have historically been treated with chemotherapy designed for colon cancer. However, an overwhelming body of molecular data has demonstrated that appendiceal adenocarcinoma is a distinct entity with key molecular differences from colon cancer, notably rare APC mutation. Recognizing that APC loss-of-function is thought to contribute to taxane resistance and that taxanes are effective in the treatment of other gastrointestinal tumors, including gastric, esophageal, and small bowel adenocarcinoma, we completed a single-center retrospective study to assess efficacy. In a cohort of 13 patients with metastatic appendiceal adenocarcinoma, treated with taxane chemotherapy the median overall survival was 8.8 months. Of 10 evaluable patients, we observed 3 responses, 4 patients with stable disease, and 3 with progression (30% response rate, 70% disease control rate). The results of this study showing activity of taxane-based chemotherapy in appendiceal adenocarcinoma support further clinical investigation of taxane therapy in this orphan disease.

Taxane-based Chemotherapy is Effective in Metastatic Appendiceal Adenocarcinoma.

Appendiceal cancer is a rare, orphan disease with no therapies currently approved by the FDA for its treatment. Given the limited data regarding drug efficacy, these tumors have historically been treated with chemotherapy designed for colon cancer. However, an overwhelming body of molecular data has demonstrated that appendiceal adenocarcinoma is a distinct entity with key molecular differences from colon cancer, notably rare APC mutation. Recognizing that APC loss-of-function is thought to contribute to taxane resistance, and that taxanes are effective in the treatment of other gastrointestinal tumors including gastric, esophageal, and small bowel adenocarcinoma, we completed a single-center retrospective study to assess efficacy. In a cohort of 13 patients with metastatic appendiceal adenocarcinoma, treated with taxane chemotherapy the median overall survival was 8.3 months. Of 10 evaluable patients we observed 3 responses, 4 patients with stable disease, and 3 with progression (30% response rate, 70% disease control rate). The results of this study showing activity of taxane-based chemotherapy in appendiceal adenocarcinoma support further clinical investigation of taxane therapy in this orphan disease.

The Future of ctDNA-Defined Minimal Residual Disease: Personalizing Adjuvant Therapy in Colorectal Cancer.

Our understanding of the diagnostic and prognostic use of circulating tumor DNA (ctDNA) in colorectal cancer (CRC) has broadly expanded over the past few years. The utilization of ctDNA to detect minimal residual disease is currently being employed across the continuum of cancer care. The lead-time of ctDNA positivity to radiographic recurrence in stage I to III CRC is up to 9 months on average, which provides a therapeutic window for a group of high-risk patients who will ultimately recur. There are several ongoing prospective clinical trials that investigate whether ctDNA can be used as an integral biomarker to risk stratify CRC patients and guide adjuvant treatment decisions. In this review, we summarize the evidence supporting the promise of ctDNA-defined MRD in CRC and highlight the current ctDNA guided adjuvant prospective clinical trials.

Going with the Flow: The Promise of Plasma-Only Circulating Tumor DNA Assays.

Circulating tumor DNA (ctDNA) has emerged as a noninvasive diagnostic and prognostic tool for colorectal cancer. Here, we discuss studies that evaluate the ability of plasma-only ctDNA assays to detect minimal residual disease and the potential benefit of integration of methylation into ctDNA assays.See related articles by Parikh et al., p. 5586 and Taieb et al., p. 5638.

Improved Survival Outcomes for Kidney Cancer Patients With Brain Metastases.

BACKGROUND: Brain metastases (BM) occur frequently in patients with metastatic kidney cancer and are a significant source of morbidity and mortality. Although historically associated with a poor prognosis, survival outcomes for patients in the modern era are incompletely characterized. In particular, outcomes after adjusting for systemic therapy administration and International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk factors are not well-known. PATIENTS AND METHODS: A retrospective database of patients with metastatic renal cell carcinoma (RCC) treated at University of Texas Southwestern Medical Center between 2006 and 2015 was created. Data relevant to their diagnosis, treatment course, and outcomes were systematically collected. Survival was analyzed by the Kaplan-Meier method. Patients with BM were compared with patients without BM after adjusting for the timing of BM diagnosis, either prior to or during first-line systemic therapy. The impact of stratification according to IMDC risk group was assessed. RESULTS: A total of 56 (28.4%) of 268 patients with metastatic RCC were diagnosed with BM prior to or during first-line systemic therapy. Median overall survival (OS) for systemic therapy-naive patients with BM compared with matched patients without BM was 19.5 versus 28.7 months (P = .0117). When analyzed according to IMDC risk group, the median OS for patients with BM was similar for favorable- and intermediate-risk patients (not reached vs. not reached; and 29.0 vs. 36.7 months; P = .5254), and inferior for poor-risk patients (3.5 vs. 9.4 months; P = .0462). For patients developing BM while on first-line systemic therapy, survival from the time of progression did not significantly differ by presence or absence of BM (11.8 vs. 17.8 months; P = .6658). CONCLUSIONS: Survival rates for patients with BM are significantly better than historical reports. After adjusting for systemic therapy, the survival rates of patients with BM in favorable- and intermediate-risk groups were remarkably better than expected and not statistically different from patients without BM, though this represents a single institution experience, and numbers are modest.

Effects of exogenous abscisic acid on fruit quality, antioxidant capacities, and phytochemical contents of southern high bush blueberries.

Abscisic acid (ABA) is a plant growth regulator that has a potential to increase antioxidant capacity and phenolic content of fruits and vegetables. The objective of this study was to examine whether an exogenous ABA application can positively affect fruit quality, antioxidant capacity, and phytochemical content of southern high bush blueberries (Vaccinium darrowii). Two varieties, namely Star and Windsor, were tested with ABA water solutions of three concentrations (0, 200, and 400ppm) using a randomised complete block design. Results showed that ABA significantly increased the firmness of berries in both varieties, suggesting a ripening delay effect. Such effect was more pronounced in Windsor variety as reflected by a lower percentage of ripe berries and smaller sized berries on ABA treated bushes. In conclusion, ABA delayed the ripening of blueberries, but did not affect total phenolic content, antioxidant capacity, or the content of individual phytochemicals in ripe blueberries.