Novel approaches to target HER2-positive breast cancer: trastuzumab emtansine.

The human epidermal growth factor receptor 2 (HER2) is overexpressed in 20% of breast carcinomas. Prior to the development of targeted therapies, HER2-positive breast cancer was associated with more aggressive disease and poor prognosis. Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate that results from the combination of trastuzumab and DM1, a derivative of the antimicrotubule agent maytansine. This molecule has the ability to enhance cytotoxic drug delivery to specifically targeted cells that overexpress HER2, therefore, maximizing efficacy while sparing toxicity. In recent years, T-DM1 has shown to improve outcomes in metastatic HER2-positive breast cancer that is resistant to trastuzumab. In addition, T-DM1 is currently being tested in the neoadjuvant and adjuvant settings to identify patients who may benefit from this therapy. This review focuses on the mechanism of action, early and late-phase clinical trials, and ongoing studies of T-DM1 in HER2-positive breast cancer.

Role of Anti-HER-2 Therapies in the Neo-Adjuvant Setting: Is Complete Pathological Response a Solid Surrogate?

Breast cancer continues to be a major health problem. Both patients and clinicians demand faster access to drugs that could result in better outcomes. In part motivated by this necessity, there has been a change in the dominant paradigm regarding how drugs become approved. Complete pathological response (pCR), understood as the absence of remanent and viable tumor after a neoadjuvant treatment, is now considered by a large proportion of the medical community as a valid surrogate. The presumption is that patients achieving pCR are less likely to develop tumor recurrence. Consequently, if a drug can improve the number of patients achieving pCR it could then obtain approval by the regulatory agencies. Pertuzumab, an anti-HER- 2 monoclonal antibody, was granted accelerated approval based on this principle. The unprecedented approval of this drug is now an example that can help us to understand the advantages but also the potential risks associated with this new approach. In this review, we will discuss the results of the two clinical trials leading to the FDA-approval of pertuzumab in the neo-adjuvant setting. We will also analyze the outcomes from long term follow up of two important neoadjuvant clinical trials, the NeoALTTO and the NOAH studies. These last ones had provided further insights regarding the magnitude, the quality as well as some limitations of the relationship between pCR and harder endpoints such as event-free or overall survival. It seems evident that the acknowledgement of pCR as a potential surrogate endpoint represents an important step in the right direction. However, it still remains controversial whether this is applicable to all subtypes of breast cancers. Additional investigations may be necessary to safely generalize this concept.

Anti-Hormonal Therapies for Premenopausal Patients--What did we Learn from the TEXT/SOFT Trials?

Between 20-25% of all breast cancers are diagnosed in patients younger than 50 years of age, most of whom are still premenopausal. Currently, tamoxifen is considered the standard of care for adjuvant treatment in these cases. However, in postmenopausal women, aromatase inhibitors (AIs) are a better choice. Given the superiority of AIs over tamoxifen in postmenopausal women, multiple investigators explored the potential role of AIs in premenopausal patients receiving ovarian suppression. Until very recently, available data derived from the ABCSG-12 clinical trial argued against the combination of AIs and ovarian suppression. This idea, however, may have changed with the release of the combined analysis of two clinical trials: SOFT and TEXT which evaluated the use of ovarian suppression in combination therapy. Clinicians will soon reconsider the possibility of using this strategy for premenopausal patients. Given the availability of this new data this review will analyze the consequences derived from this study, contextualize this new information within the vast available literature of anti-hormonal therapy, and discuss potential arguments in favor of and against the use of this approach.

Recent treatment advances and novel therapies in pancreas cancer: a review.

PURPOSE: Over the last couple of years, we have witnessed the availability of a wide variety of different therapeutic agents and the identification of effective combinations of existing ones that have transformed the way we approach and treat pancreatic cancer. Proof of this are the recent validations that combinations of conventional chemotherapy drugs, the FOLFIRINOX regimen and gemcitabine plus nab-paclitaxel, significantly improves clinical outcomes in patients with metastatic disease. However, deeper and more sophisticated understanding of the biology of this cancer as well as the ability to develop better and perhaps more precise drugs predict that the landscape may be changing even more. METHODOLOGY AND RESULTS: In this review, we will summarize the most recent treatment advances including FOLFIRINOX, gemcitabine plus nab-paclitaxel and discuss novel approaches such as immune-mediated therapies, drugs that disrupt the tumor-stromal compartment, PARP inhibitors for BRCA pathway-deficient pancreatic cancer and new generations of conventional chemotherapeutics, which are in early phases of clinical development and have shown promising early results. We will also discuss some examples of drugs that failed, despite very good preliminary data, in order to appraise the lessons learned from these negative clinical trials. Lastly, we will comment on ongoing adjuvant and neoadjuvant trials. CONCLUSION: We hope that at least some of these will result in positive trials and add to our armamentarium for treating this challenging malignancy.

Advances and new perspectives in the treatment of metastatic colon cancer.

During the last decade we have witnessed an unprecedented outburst of new treatment approaches for the management of metastatic colon cancer. Anti-angiogenic drugs, epidermal growth factor receptor blockers and multi-kinase inhibitors have all resulted in small but consistent improvement in clinical outcomes. However, this progress has paradoxically leaded us into new challenges. In many cases the clinical development was done in parallel and the lack of head-to-head comparison evolved into circumstances where several valid new "standards of care" are available. Even though desirable in essence, the availability of many options as well as different possible combinations frequently leaves the busy clinician in the difficult situation of having to choose between one or the other, sometimes without solid evidence to support each decision. In addition, progress never stops and new agents are continuously tested. For these reason this review will try to summarize all the clinical trials that constitute the theoretical framework that support our daily practice but will also procure the reader with rational answers to common clinical dilemmas by critically appraising the current literature. Lastly, we will provide with a compilation of promising new agents that may soon become our next line of defense against this deadly disease.

Therapeutic options for HER-2 positive breast cancer: Perspectives and future directions.

During the last 15 years we have witnessed an unprecedented expansion in the drugs developed to target human epidermal growth factor receptor-2 (HER-2) positive breast cancer. Trastuzumab, pertuzumab, ado-trastuzumab emtansine and lapatinib are currently food and drug administration (FDA)-approved for the treatment of breast cancer patients with HER-2 over-expressed. However, given the amount of information gathered from years of uninterrupted clinical research, it is essential to have periodic updates that succinctly recapitulate what we have learnt over these last years and help us to apply that information in our daily practice. This review will pursue that objective. We will summarize the most relevant and updated information related to the state of the art management of HER-2 positive breast cancer in all the clinical scenarios including the adjuvant, neoadjuvant and metastatic settings. But we will also critically appraise that literature in order to highlight some key clinical concepts that should not be overlooked. Lastly, this review will also point out some of the most promising strategies that are currently being tested and may soon become available.

Novel targeted agents for the treatment of advanced breast cancer.

The discovery of the molecular processes involved in cancer development has led to the design of an array of targeted agents. These agents, directed to specific proteins in the machinery of cancer cells, interfere with vital cascades involved in cell invasion, metastasis, apoptosis, cell-cycle control and angiogenesis. In breast cancer, the main pathways studied and targeted by drugs are the HER2 pathway, EGFR, VEGF, PI3K/Akt/mammalian target of rapamycin (PI3K-M-Tor), IGF/IGFR, poly(ADP ribose) polymerase 1, HDAC and many others. In this review, we present the most promising studies of these new targeted therapies and novel combination of targeted therapies with cytotoxic agents for the treatment of breast cancer patients.

Trastuzumab subcutaneo en el tratamiento del cancer de mama HER2 positivo / Subcutaneous trastuzumab in breastcancer treatment of her2 positive

La sobreexpresión o amplificación del receptor HER2 seobserva en el 20% de pacientes con cáncer de mama y seasocia con un pronóstico adverso. El agente anti HER2más ampliamente utilizado en la clínica es el trastuzumab,anticuerpo monoclonal. El tratamiento adyuvante tieneuna duración de 12 meses y en cáncer de mama metastásicose continúa más allá de la progresión. La mayoría delos pacientes recibirá trastuzumab durante 1 año, muchosrecibirán 2 a 3 años, y algunos han recibido/recibirán más de8 años. Surge así un interés creciente por la vía subcutánea(SC) de administración: menos invasiva, menos costosay más cómoda. El estudio HannaH, ensayo de fase III,abierto y aleatorizado, utilizó una dosis fija subcutánea de600 mg de trastuzumab en combinación con quimioterapianeoadyuvante y la comparó con la vía de administraciónendovenosa (EV) aprobada. Se incluyeron pacientes concáncer de mama HER2 (+) operable, localmente avanzado einflamatorio. Los objetivos primarios fueron: concentraciónsérica mínima predosis del ciclo 8 y respuesta patológicacompleta. Se aleatorizaron 299 pacientes a trastuzumab EVy 297 a trastuzumab SC. La concentración sérica mínimamedia fue 57.8 μ/ml en el grupo EV y 78.7 en el grupo SC.El 40.7% de los pacientes en el grupo EV y el 45.4% en elgrupo SC logró respuesta patológica completa. TrastuzumabSC resultó no inferior para ambos objetivos primarios.La incidencia de eventos adversos grados 3 a 5 fue similar enambos grupos. La demostración de no-inferioridad sugiereque el trastuzumab SC ofrece una válida y más convenientealternativa al trastuzumab EV.

Overexpression or amplification of HER2 is found in 20%of patients with breast cancer and is associated with anunfavourable prognosis. Trastuzumab is the anti HER2agent most widely used in clinical practice. Adjuvanttreatment should be given during 12 months, and in themetastatic setting treatment should continue beyond progression.Most patients will receive treatment during oneyear, many will be treated during 2 to 3 years, and somepatients will remain in treatment for more than 8 years.In this context, a subcutaneous route of administrationbecomes an attractive option: less invasive, less costly,and more comfortable for patients. The HannaH study is a phase III, open, randomized clinical trial that used a fixedsubcutaneous dose of 600 mg of trastuzumab in combinationwith neoadjuvant chemotherapy and compared it tothe approved intravenous (IV) route of administration.Patients with HER2 (+) operable, locally advanced andinflammatory breast cancer were included in the study.Primary endpoints included: serum trough concentrationpre-dose cycle 8 and pathologic complete response. Twohundred and ninety-nine patients were randomized to IVtrastuzumab and 297 to SC trastuzumab. Mean serumtrough concentration was 57.8 μ/ml in the IV group and78.7 in the SC group. In the IV group 40.7% of patientsachieved pathologic complete response, and 45.4% in the SCgroup. The SC formulation resulted non-inferior for bothprimary objectives. Incidence of grade 3-5 adverse eventswas similar in both groups. The non-inferior results suggestthat SC trastuzumab is a valid and more convenientalternative to IV trastuzumab.

Tratamiento medico del cancer colorrectal / Medical treatment of colorectal cancer

El cáncer de intestino grueso es, en los EE UU, la segunda causa de mortalidad por câncer en ambos sexos despues del cáncer de pulmón. Se estima que en 1995 los tumores malignos del colon y recto se ubicarón en el tercer lugar como neoplasias má frecuentes siguiendo a los cánceres de pulmón y próstata en el hombre y detrás de los de pulmón y mama en la mujer. Los factores etiológicos del cáncer colorrectal se desconocen aunque se han implicado factores ambientales, genéticos, dietarios y familiares. En cuanto al tratamiento es importante recalcar que estos tumores son curables en un porcentaje significativo de pacientes cuando es detectado a tiempo. La terapia adyuvante con 5-fluorouracilo (5-FU) y levamisole (lev) incrementó la tasa de curación en pacientes con cáncer de colon estadío III o Dukes'C. En pacientes con cáncer de recto, el tratamiento adyuvante combinando quimioterapia y radioterapia incrementó la tasa de curación en pacientes con estadíos II (Dukes'B-2) y III. Cuando el cáncer colorrectal ha metastatizado a distancia (estadío IV o Dukes D) es incurable en la inmensa mayoría de los casos. De hecho la única possibilidad curativa en este grupo de pacientes es, cuando esté indicado, la resección quirúrgica de la/s matástasis. Cuando esto no es posible el tratamiento que se recomienda es 5-FU solo o en combinación con otros fármacos con fines paliativos. A pesar de los avances logrados en los últimos años, todavía la mitad de los pacientes con cáncer colorrectal mueren a causa de progresión de su enfermedad. Mejoras en la prevención primaria y secundaria, nuevas modalidades terapéuticas y mejores agentes quimioterapéuticos será necesarios para mejorar la sobrevida en el grupo de pacientes afectados por esta enfermedad.