Advanced renal cell carcinoma management: the Latin American Cooperative Oncology Group (LACOG) and the Latin American Renal Cancer Group (LARCG) consensus update.

PURPOSE: Renal cell carcinoma is an aggressive disease with a high mortality rate. Management has drastically changed with the new era of immunotherapy, and novel strategies are being developed; however, identifying systemic treatments is still challenging. This paper presents an update of the expert panel consensus from the Latin American Cooperative Oncology Group and the Latin American Renal Cancer Group on advanced renal cell carcinoma management in Brazil. METHODS: A panel of 34 oncologists and experts in renal cell carcinoma discussed and voted on the best options for managing advanced disease in Brazil, including systemic treatment of early and metastatic renal cell carcinoma as well as nonclear cell tumours. The results were compared with the literature and graded according to the level of evidence. RESULTS: Adjuvant treatments benefit patients with a high risk of recurrence after surgery, and the agents used are pembrolizumab and sunitinib, with a preference for pembrolizumab. Neoadjuvant treatment is exceptional, even in initially unresectable cases. First-line treatment is mainly based on tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs); the choice of treatment is based on the International Metastatic Database Consortium (IMCD) risk score. Patients at favourable risk receive ICIs in combination with TKIs. Patients classified as intermediate or poor risk receive ICIs, without preference for ICI + ICIs or ICI + TKIs. Data on nonclear cell renal cancer treatment are limited. Active surveillance has a place in treating favourable-risk patients. Either denosumab or zoledronic acid can be used for treating metastatic bone disease. CONCLUSION: Immunotherapy and targeted therapy are the standards of care for advanced disease. The utilization and sequencing of these therapeutic agents hinge upon individual risk scores and responses to previous treatments. This consensus reflects a commitment to informed decision-making, drawn from professional expertise and evidence in the medical literature.

The roles of PTEN, cMET, and p16 in resistance to cetuximab in head and neck squamous cell carcinoma.

There is no established biomarker for cetuximab efficacy in recurrent head and neck squamous cell carcinoma (HNSCC). The aim of the present study was to evaluate the prognostic and predictive impact of PTEN, cMET, and p16 expression in recurrent HNSCC. In this retrospective study, 112 patients with recurrent HNSCC received chemotherapy (CT) alone (n = 37) or chemotherapy with cetuximab (n = 75). PTEN, cMET, and p16 protein expression were evaluated by immunohistochemistry. The median overall survival (mOS) for the patients treated with cetuximab + CT versus CT alone was 11.4 months and 7.0 months, (p = 0.949). The median progression-free survival (mPFS) was 6.2 months versus 3.0 months (p = 0.154). Patients with PTEN loss exhibited a mOS of 5.8 months versus 10.5 months (p = 0.002) and a mPFS of 3.2 months versus 4.7 months (p = 0.019). A multivariate analysis identified an independent association between PTEN loss and OS (HR 2.27; 95% confidence 95% CI 1.27-4.08; p = 0.006) and with PFS (HR 1.85; 95% CI 1.09-2.99; p = 0.022). A negative prognostic impact of PTEN loss was observed in the patients treated with cetuximab + CT, and not in the CT only group. Expression of cMET and p16 showed no impact on OS or PFS. The present findings confirm that PTEN is a prognostic factor for metastatic HNSCC and they support further studies of PTEN expression to evaluate its predictive value to cetuximab response.

MRP1 expression in CTCs confers resistance to irinotecan-based chemotherapy in metastatic colorectal cancer.

Circulating tumor cells are important markers of tumor progression and can reflect tumor behavior in metastatic colorectal cancer (mCRC). Identification of proteins that confer resistance to treatment is an important step to predict response and better selection of treatment for patients. Multidrug resistance-associated protein 1 (MRP1) and Multidrug resistance-associated protein 4 (MRP4) play a role in irinotecan-resistance, and Excision Repair Cross-Complementation group 1 (ERCC1) expression can confer resistance to platinum compounds. Here, we included 34 patients with mCRC and most of them received FOLFIRI or FOLFOX chemotherapy (91.1%). CTCs were isolated by ISET(®) Technology and identified in 30 patients (88.2%), with a median of 2.0 CTCs/mL (0-31.0). We analyzed the immunocytochemical expression of MRP1, MRP4 and ERCC1 only in patients who had previously detectable CTCs, accordingly to treatment received (n = 19, 15 and 13 patients, respectively). Among patients treated with irinotecan-based chemotherapy, 4 out of 19 cases with MRP1 positive CTCs showed a worse progression free survival (PFS) in comparison to those with MRP1 negative CTCs (2.1 months vs. 9.1 months; p = 0.003). None of the other proteins studied in CTCs had significant association with PFS. We analyzed also histological sections of primary tumors and metastases by immunohistochemistry, and found no association with clinicopathological characteristics or with PFS. Our results show MRP1 as a potential biomarker of resistance to treatment with irinotecan when found in CTCs from mCRC patients. This is a small proof-of-principle study and these early findings need to be validated in a larger cohort of patients.

Thymidylate synthase expression in circulating tumor cells: a new tool to predict 5-fluorouracil resistance in metastatic colorectal cancer patients.

Thymidylate synthase (TYMS) is an important enzyme for 5-fluorouracil (5-FU) metabolism in metastatic colorectal cancer (mCRC) patients. The search for this enzyme in circulating tumor cells (CTCs) can be a powerful tool to follow-up cancer patients. mCRC patients were enrolled before the beginning of 5-FU-based chemotherapy. The blood was filtered on Isolation by Size of Epithelial Tumor Cells (ISET), and the analysis of TYMS expression in CTCs was made by immunocytochemistry. Additionally, we verified TYMS staining in primary tumors and metastases from the same patients. There were included 54 mCRC patients and 47 of them received 5-FU-based chemotherapy. The median CTCs number was 2 per mL. We were not able to analyze immunocytochemistry in 13 samples (9 patients with absence of CTCs and 4 samples due to technical reasons). Therefore, TYMS expression on CTCs was analyzed in 34 samples and was found positive in 9 (26.5%). Six of these patients had tumor progression after treatment with 5-FU. We found an association between CTC TYMS staining and disease progression (DP), although without statistical significance (P = 0.07). TYMS staining in primary tumors and metastases tissues did not have any correlation with disease progression (P = 0.67 and P = 0.42 respectively). Patients who had CTC count above the median (2 CTCs/mL) showed more TYMS expression (P = 0.02) correlating with worse prognosis. Our results searching for TYMS staining in CTCs, primary tumors and metastases suggest that the analysis of TYMS can be useful tool as a 5-FU resistance predictor biomarker if analyzed in CTCs from mCRC patients.