Resistance to trastuzumab in patients with HER2-overexpressing breast cancer is associated with higher risk of progression or cancer death, and might be related to activation of PI3K/AKT/mTOR and Ras/Raf/MAPK signaling cascades and a decreased level of their inhibitor (PTEN). HER2-overexpressing breast cancer patients (n = 75) treated with radical local therapy and trastuzumab in adjuvant setting were included into the study. Deoxyribonucleic acid isolated from paraffin sections was used to assess mutational status of the PIK3CA gene (p.H1047R and p.E545K mutations) by the quantitative polymerase chain reaction technique. Expression of selected proteins (ER, PgR, AR, Ki-67, EGFR) was assessed using immunohistochemistry. In the studied group we found significantly higher Ki-67LI in EGFR-positive carcinomas (p = 0.048). Moreover, EGFR immunonegativity was observed more frequently in low-grade (G1/G2) carcinomas as well as in estrogen/progesterone and androgen receptor immunopositive tumors (p = 0.042, p = 0.016, p = 0.044, respectively). Favorable metastasis-free survival was observed in patients with pN0 and pN1 (vs. pN2+3) stage (p = 0.040) and with tumors characterized by low Ki-67LI (≤ 50% vs. > 50%) (p = 0.014). Patients with tumor androgen receptor immunonegativity (weak or lack of expression) or strong PTEN expression survived 3 years without metastases (p = 0.007). The results of our study suggest that androgen receptor and PTEN status might be considered as indicators of trastuzumab sensitivity.

Introduction : Treatment of the metastatic stage of renal cell carcinoma is specific because classical chemotherapy is not applicable here. The treatment is mainly based on molecularly targeted drugs, including inhibitors of tyrosine kinases. In many cases the therapy takes many months, and...

Aim: Resistance to trastuzumab (which is a standard therapy for breast cancer patients with HER2 overexpression) is associated with higher risk of progression or cancer death, and might be related to activation of signalling cascades (PI3K/AKT/mTOR, Ras/Raf/MAPK) and decreased level of their inhibitors.

Despite the advancements made in oncology in recent years, the treatment of pancreatic cancer remains a challenge. Five-year survival rates for this cancer do not exceed 10%. Among the reasons contributing to poor treatment outcomes are the oligosymptomatic course of the tumor, diagnostic difficulties due to the anatomical location of the organ, and the unique biological features of pancreatic cancer. The mainstay of treatment for resectable cancer is surgery and adjuvant chemotherapy. For unresectable and metastatic cancers, chemotherapy remains the primary method of treatment. At the same time, for about thirty years, there have been attempts to improve treatment outcomes by using radiotherapy combined with systemic treatment. Unlike chemotherapy, radiotherapy has no established place in the treatment of pancreatic cancer. This paper addresses the topic of radiotherapy in pancreatic cancer as a valuable method that can improve treatment outcomes alongside chemotherapy.

Introduction: Systemic treatment of pancreatic adenocarcinoma in the population of people over 65 years old is a challenge resulting from both the extremely unfavourable prognosis of this cancer and the particularly high sensitivity to the toxicity of chemotherapy in the elderly. This article...