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Nowadays, notothenioids are the teleostean group that dominates marine Antarctic waters. However, during the Mesozoic a diverse ichthyofauna inhabited the sea that surrounded Antarctic. We present the preliminary results of the last two Argentinian Antarctic field expedition to the Late Jurassic of Antactic Peninsula (Longing Gape) and Cretaceous-Paleogene of Seymour (=Marambio) Island. The fish material recovered is extremely abundant and their further detailed study may provide significant clues into the taxonomy and paleobiogeography of the mesozoic antactic ichthyofaunas.

Las formaciones Sobral y Cross Valley (Paleoceno) están limitadas por discordancias y constituyen parte del relleno cuspidal de la cuenca James Ross, extremo NE de la Península Antártica. Ambas presentan discontinuidades internas que permiten subdividirlas en alomiembros. La Formación Sobral representa sedimentación silicoclástica de plataforma marina durante al menos dos ciclos regresivos-transgresivos. La Formación Cross Valley rellena un valle angosto con depósitos volcanoclásticos de relleno de valle inciso con canales estuarinos que rematan en depósitos de planicie deltaica. Las areniscas de la Formación Sobral son feldarenitas líticas y litoarenitas feldespáticas, las de la Formación Cross Valley son litoarenitas feldespáticas y litoarenitas (volcánicas). Su estudio composicional sugiere un progresivo incremento en el aporte desde un arco volcánico que habría incrementado su actividad durante el Daniano cesando hacia el Thanetiano superior. La variación composicional de las areniscas permitió diferenciar dos petrofacies (S y CV respectivamente) con dos subpetrofacies (S I, S II, CV I y CV II). Estas sugieren un control de los ambientes sedimentarios sobre las modas detríticas e interferencia con la señal de procedencia. La alta proporción de cuarzo y glauconita en algunas unidades puede relacionarse con superficies de erosión, el retrabajo de unidades subyacentes cortadas por dichas superficies y/o con ambientes depositacionales de mayor energía. Los componentes volcánicos y metamórficos se relacionan con el área de procedencia. Se postula la superposición de dos fuentes predominantes de detritos, una extra y otra intracuencal. La primera representa la denudación de un arco volcánico episódicamente activo, con exposición de sus raíces plutónicas y metamórficas, ubicado en la actual península Antártica. Esta fuente se caracteriza por aportar los fragmentos líticos volcánicos y en menor medida metamórficos con porcentajes variables de cuarzo y feldespatos. La representación de estas rocas en los diagramas de procedencia indican orógenos reciclados (y mezcla) durante los períodos de mayor denudación y arcos disectados a no disectados luego de episodios de vulcanismo activo. El alto porcentaje de cuarzo en algunas secciones señala el enriquecimiento en fragmentos resistentes a partir del retrabajo de las sedimentitas subyacente favorecido por el carácter friable de las mismas y/o el desarrollo de ambientes de sedimentación de alta energía y/o baja velocidad de soterramiento.The unconformity bounded Paleocene Sobral and Cross Valley formations represent part of the uppermost infill of the James Ross Basin of northeastern Antarctic Peninsula. Both units have been subdivided into allomembers since they also present internal unconformities. The Sobral Formation represents silicoclastic sedimentation on a marine shelf during at least two transgressive-regressive cycles. The Cross Valley Formation fills in a narrow valley with volcaniclastic deposits representing an incised valley system with estuarine and subsequent deltaic facies. Sandstones of the Sobral Formation are feldspathic litharenites and lithic arkoses while those of the Cross Valley Formation are feldspathic litharenites to litharenites (volcanic). The sandstone composition (petrofacies) of the Sobral and Cross Valley formation suggest provenance from a dissected volcanic arc that increased its activity during the Danian but decline again towards the late Thanetian. A detailed analysis of the sandstone compositional trends allowed to differentiate two petrofacies (S and CV) and two sub-petrofacies (S I, S II, CV I and CV II respectively). The sub-petrofacies suggest a control from the sedimentary environments upon the detrital modes and their interference with the true provenance signal. The increase in quartz and glauconite in some units may be related to the unconformities and reworking of the underlying sedimentary units as well as development of high energy environments. On the other hand, volcanic, plutonic and metamorphic rock fragments are related to the provenance area. The overlap of two main sources of sediments, one from the basin edge and other within the basin is then envisaged. The first one represents the unroofing of a volcanic arc located at the present day position of the Antarctic Peninsula. This source shed volcanic rock fragments and minor metamorphic rock fragments with variable amount of quartz and feldspars. This composition plots within the recycled orogen and dissected arc fields of the provenance diagrams representing periods of arc inactivity and deep erosion and plots within the volcanic arc fields after times of volcanic activity. On the other hand, sandstones with high proportion of quartz recorded at specific levels within the sequence suggests breakdown of less resistant components and reworking of the loose underlying sedimentary rocks favoured by low sedimentary rates and/or in high energy environments.

Purpose: To evaluate the efficacy of adding lapatinib to capecitabine and oxaliplatin (CapeOx) in patients with previously untreated human epidermal growth factor receptor 2 (HER2) -amplified advanced gastroesophageal adenocarcinoma., Patients and Methods: Patients with HER2-positive advanced gastroesophageal adenocarcinoma were randomly assigned at a one-to-one ratio to CapeOx plus lapatinib 1,250 mg or placebo daily. Primary end point was overall survival (OS) in patients with centrally confirmed HER2 amplification in the primary efficacy population., Results: A total of 545 patients were randomly assigned, and 487 patients comprised the primary efficacy population. Median OS in the lapatinib and placebo arms was 12.2 (95% CI, 10.6 to 14.2) and 10.5 months (95% CI, 9.0 to 11.3), respectively, which was not significantly different (hazard ratio, 0.91; 95% CI, 0.73 to 1.12). Median progression-free survival in the lapatinib and placebo arms was 6.0 (95% CI, 5.6 to 7.0) and 5.4 months (95% CI, 4.4 to 5.7), respectively (hazard ratio, 0.82; 95% CI, 0.68 to 1.00; P = .0381). Response rate was significantly higher in the lapatinib arm: 53% (95% CI, 46.4 to 58.8) compared with 39% (95% CI, 32.9 to 45.3) in the placebo arm (P = .0031). Preplanned exploratory subgroup analyses showed OS in the lapatinib arm was prolonged in Asian and younger patients. No correlation was observed between HER2 immunohistochemistry status and survival. There were increased toxicities in the lapatinib arm, particularly diarrhea., Conclusion: Addition of lapatinib to CapeOx did not increase OS in patients with HER2-amplified gastroesophageal adenocarcinoma. There were clear differences in the effect of lapatinib depending on region and age. Future studies could examine this correlation., (© 2015 by American Society of Clinical Oncology.)

Purpose: This multicenter phase III study evaluated the efficacy and safety of lapatinib, an epidermal growth factor receptor/ErbB2 inhibitor, administered concomitantly with chemoradiotherapy and as maintenance monotherapy in patients with high-risk surgically treated squamous cell carcinoma of the head and neck (SCCHN)., Patients and Methods: Patients with resected stage II to IVA SCCHN, with a surgical margin ≤ 5 mm and/or extracapsular extension, were randomly assigned to chemoradiotherapy (66 Gy total radiation dose and cisplatin 100 mg/m(2) per day administered on days 1, 22, and 43) plus placebo or lapatinib (1,500 mg per day) before and during chemoradiotherapy, followed by 12 months of maintenance monotherapy., Results: Six hundred eighty-eight patients were enrolled (lapatinib, n = 346; placebo, n = 342). With a median follow-up time of 35.3 months, the study ended early because of the apparent plateauing of disease-free survival (DFS) events. Median DFS assessed by an independent review committee was 53.6 months and not reached for lapatinib and placebo, respectively (hazard ratio, 1.10; 95% CI, 0.85 to 1.43). Investigator-assessed results confirmed the independent review committee assessment. No significant differences in DFS by human papillomavirus status or overall survival were observed between treatment arms. Similar numbers of patients in both treatment arms experienced adverse events (AEs), with more patients in the lapatinib arm than the placebo arm experiencing serious AEs (48% v 40%, respectively). The most commonly observed treatment-related AEs were diarrhea and rash, both predominantly in the lapatinib arm., Conclusion: Addition of lapatinib to chemoradiotherapy and its use as long-term maintenance therapy does not offer any efficacy benefits and had additional toxicity compared with placebo in patients with surgically treated high-risk SCCHN., (© 2015 by American Society of Clinical Oncology.)

Purpose: CEREBEL compared the incidence of CNS metastases as first site of relapse in patients with human epidermal growth factor receptor 2-positive metastatic breast cancer receiving lapatinib-capecitabine or trastuzumab-capecitabine., Patients and Methods: Patients without baseline CNS metastases were randomly assigned (1:1) to receive lapatinib-capecitabine (lapatinib 1,250 mg per day; capecitabine 2,000 mg/m(2) per day on days 1 to 14 every 21 days) or trastuzumab-capecitabine (trastuzumab loading dose of 8 mg/kg followed by an infusion of 6 mg/kg every 3 weeks; capecitabine 2,500 mg/m(2) per day on days 1 to 14 every 21 days). The primary end point was incidence of CNS metastases as first site of relapse. Secondary end points included progression-free survival (PFS) and overall survival (OS)., Results: The study was terminated early with 540 enrolled patients (271 received lapatinib-capecitabine, and 269 received trastuzumab-capecitabine). Incidence of CNS metastases as first site of relapse was 3% (eight of 251 patients) for lapatinib-capecitabine and 5% (12 of 250 patients) for trastuzumab-capecitabine (treatment differences, -1.6%; 95% CI, -2% to 5%; P = .360). PFS and OS were longer with trastuzumab-capecitabine versus lapatinib-capecitabine (hazard ratio [HR] for PFS, 1.30; 95% CI, 1.04 to 1.64; HR for OS, 1.34; 95% CI, 0.95 to 1.64). Serious adverse events were reported in 13% (34 of 269 patients) and 17% (45 of 267 patients) of patients in the lapatinib-capecitabine and trastuzumab-capecitabine arms, respectively., Conclusion: CEREBEL is inconclusive for the primary end point, and no difference was detected between lapatinb-capecitabine and trastuzumab-capecitabine for the incidence of CNS metastases. A better outcome was observed with trastuzumab-capecitabine in the overall population. However, lapatinib-capecitabine efficacy may have been affected by previous exposure to a trastuzumab regimen and/or when treatment was given as first- or second-line therapy in the metastatic setting., (© 2015 by American Society of Clinical Oncology.)