Preclinical and clinical development of palbociclib and future perspectives.

Cyclin-dependent kinases (CDKs) play a key role in cell cycle regulation, which makes them a clear therapeutic target to interfere with cell division and proliferation in cancer patients. Palbociclib, a specific inhibitor of CDK4/6 with outstanding clinical efficacy data and limited toxicity, has been recently approved for the treatment of hormone receptor (HR)-positive human epidermal growth factor receptor 2 (HER2)-negative locally advanced or metastatic breast cancer, either in combination with an aromatase inhibitor or in combination with fulvestrant in women who have received prior endocrine therapy. This review describes the mechanism of action, preclinical experiences and clinical data of palbociclib, with a special focus on integrating this data with the positioning of palbociclib in the current clinical guidelines for advanced HR-positive/HER2-negative breast cancer. Aspects of the ongoing major studies are also presented, as well as future prospects in the development of palbociclib.

Preventive treatments for breast cancer: recent developments.

Breast cancer is a burden for western societies, and an increasing one in emerging economies, because of its high incidence and enormous psychological, social, sanitary and economic costs. However, breast cancer is a preventable disease in a significant proportion. Recent developments in the armamentarium of effective drugs for breast cancer prevention (namely exemestane and anastrozole), the new recommendation from the National Institute for Health and Care Excellence to use preventative drugs in women at high risk as well as updated Guidelines from the US Preventive Services Task Force and the American Society of Clinical Oncology should give renewed momentum to the pharmacological prevention of breast cancer. In this article we review recent major developments in the field and examine their ongoing repercussion for breast cancer prevention. As a practical example, the potential impact of preventive measures in Spain is evaluated and a course of practical actions is delineated.

Subcutaneous trastuzumab: drug development and current position.

HER2-positive breast cancer, accounting for 15 % of the total breast cancer patient population, carries in itself a bad prognosis, which has now become much better after the advent of anti-HER2 drugs. HER2-targeted therapy has significantly improved disease free- and overall survival in HER2-positive breast cancer, and has rendered better disease control both in the early and advanced disease setting. Trastuzumab treatment duration is often prolonged and poses significant time and resource challenges both on the treatment institutions and on the patient. The recent development of a subcutaneous formulation has meant a significant advance in this respect. We review the drug development of the compound and the current evidence on its use.

[Breast cancer metastases in the iris: does treatment modifies natural history of the illness?]. / Metástasis en iris de un carcinoma de mama: ¿modifica el tratamiento la historia natural de la enfermedad?

The 4-5% of the breast cancer patients have metastases in the eye. We present the case of a 30-year-old woman with an infiltrant duct carcinoma of the breast pT2N2M0 HER2 positive. Six months after primary radical treatment she had a systemic relapse with multiples metastatic sites, so several treatment with trastuzumab in combination with chemotherapy were started. After 4 years patient presented multiple white-coloured micronodules in the iris of the right eye. Only a 3-7.8% of ocular metastases are located in the iris. With mantenaince therapy with trastuzumab natural history of the illness has changed. Several studies had analyzed if metastases in the brain during treatment with trastuzumab have increased in comparison with the pretrastuzumab era. The infrequent presentation of metastases in the anterior uveal makes difficult to establish if it is an spontaneous fact or if it is favoured by trastuzumab treatment.

[Receptors for epidermal growth factor in breast cancer]. / Receptores del factor de crecimiento epidérmico en cáncer de mama.

Epidermal growth factor receptor (EGFr) and cytosolic (cER) and nuclear (nER) estradiol receptors were quantified in 220 primary breast cancers. The EGFr was significantly more frequent (X2 = 5.9; P less than 0.025) and its concentration was significantly higher (P less than 0.001) among ER- tumors than in ER+ tumors. There was a significantly greater proportion (X2 = 6.4; P less than 0.05) of node involvement in EGFr+/ER+ tumors than in EFGr/ER+. Increases in the proportion of EGFr+ in ER- tumors are parallel to Scarff-Bloom scores (X2 = 6.1; P less than 0.05) and there is a significant trend towards increased EGFr concentrations with histologic dedifferentiation. In ER+ tumors the median concentrations of EGFr in the different age groups show linear correlation and follow a parallel profile with the medians of nER. These findings support the hypothesis that considers EGFr as a bad prognosis factor and suggest that EGFr expression and concentration in ER+ tumors might be considered an estrogenic action mediated through the binding of ER to their nuclear acceptors.

p29 protein in breast cancer: relation between estrogen and progesterone receptors.

An immunoradiometric assay was used to determine the presence of p29 protein in 68 breast cancer cyTOSOLS. The p29 values ranged from 0 to 1123 U/mg, with a mean value of 127 +/- 28.7 U/mg. Using a cutoff point of 20 U/mg the frequency of p29 positive tumors was about 55%. A quantitative and qualitative relation was found between p29 and estrogen receptor (ER), but not between p29 and progesterone receptor (PR). Discordance between p29 and ER status was found in 13 out of 68 tumors. Both the frequency of p29 positive tumors and the p29 values were significantly higher in postmenopausal than in premenopausal women, in a similar way to ER but different from PR. There was no difference in p29 content between primary tumor and metastasis. We did not find any relation among p29 primary tumors content and axillary lymph nodes involvement or tumor size.

Adjuvant chemotherapy with adriamycin, fluorouracil, cyclophosphamide, methotrexate, with or without tamoxifen in operable breast cancer.

Between January 1982 and February 1985, 70 breast cancer patients with histologically confirmed axillary node involvement and T1-3a were treated following surgery with a combination of adriamycin, fluorouracil, cyclophosphamide, methotrexate, with or without tamoxifen according to the estrogen and progesterone receptors state. At 60 months of study (median follow-up, 41 months), the estimated proportion remaining disease-free was 62%. The estimated survival rate was 81%. A comparison of the actuarial disease-free and overall survival with data reported in the literature indicates a similar positive effect of adjuvant systemic therapy as described in adjuvant studies using polychemotherapy regimens. Patient acception of chemotherapy regimen was generally good. This can be accounted for because of an adequate emesis control and real compliance of the patients with the oncologist.