Case 304: Porphyria Cutanea Tarda.

HISTORY: In 2017, a 72-year-old woman was seen in the gastroenterology department with a 2-month history of mild and intermittent abdominal pain without other accompanying symptoms. Her medical history was unremarkable, except for a previous visit due to facial photodermatitis 3 years earlier. Diazepam for a sleeping disorder was the only chronic medication recorded. Results of physical examination, blood count, and basic metabolic panels including assessment of renal and liver function were normal; only the ferritin level was slightly elevated (265 ng/mL [595 pmol/L]; normal range, 10-120 ng/mL [22-269 pmol/L]). Abdominal US was performed, followed by multiphasic contrast-enhanced CT and liver MRI due to the findings of the first study. A diagnosis was not established in that moment, and acetaminophen was prescribed for pain relief. As the symptoms continued, laboratory tests and imaging studies were repeated 2 years later, with similar findings and no notable changes.

Case 304.

History In 2017, a 72-year-old woman was seen in the gastroenterology department with a 2-month history of mild and intermittent abdominal pain without other accompanying symptoms. Her medical history was unremarkable, except for a previous visit due to facial photodermatitis 3 years earlier. Diazepam for a sleeping disorder was the only chronic medication recorded. Results of physical examination, blood count, and basic metabolic panels including assessment of renal and liver function were normal; only the ferritin level was slightly elevated (265 ng/mL [595 pmol/L]; normal range, 10-120 ng/mL [22-269 pmol/L]). Abdominal US was performed, followed by multiphasic contrast-enhanced CT and liver MRI due to the findings of the first study. A diagnosis was not established in that moment, and acetaminophen was prescribed for pain relief. As the symptoms continued, laboratory tests and imaging studies were repeated 2 years later, with similar findings and no notable changes (Figs 1-5).

Multicentric infantile myofibromatosis with extensive involvement limited to bone.

Infantile myofibromatosis (IM) is the most common benign fibrous tumor of infancy, characterized by the development of single or multiple nodules in the skin, soft tissues, bone, and/or viscera. Multicentric forms are less frequent and can affect different tissues simultaneously and their prognosis depends on their extension and visceral involvement. Rarely, these forms are limited to the skeleton, in which case the absence of extraosseous lesions makes it difficult to suspect this entity. We present the case of an infant with multiple radiolucent lesions involving the skull, ribs, spine, and long bones, discovered in a radiological study performed after a minor trauma. A broad differential diagnosis was considered based on the osteolytic and polyostotic nature of the lesions on imaging studies. This report details and illustrates the typical radiological findings in bony involvement of IM, which suggest this disorder over other diagnostic options.

Mechanisms Behind the Resistance to Trastuzumab in HER2-Amplified Breast Cancer and Strategies to Overcome It.

The introduction of trastuzumab therapy markedly improved the poor prognosis associated with HER2-amplified breast cancers. Despite this, the presence of primary and acquired resistance to trastuzumab treatment remains a significant common challenge. The identification of resistance mechanisms and the incorporation of new drugs that achieve a better blockade of HER family receptors signaling have resulted in improved outcomes. The phosphatidylinositol 3'-kinase/protein kinase B/mammalian target of rapamycin pathway, cross-talk with estrogen receptors, immune response, cell cycle control mechanisms, and other tyrosine kinase receptors such as insulin-like growth factor I receptor are potential pathways involved in trastuzumab resistance. Different therapeutic interventions targeting these pathways are currently under evaluation.

Reduced folate carrier (RFC) as a predictive marker for response to pemetrexed in advanced non-small cell lung cancer (NSCLC).

INTRODUCTION: RFC is the major transport system in mammalian cells for folate cofactors and antifolate therapeutics. The aim of this study was to assess the predictive value of RFC expression in patients receiving pemetrexed for advanced NSCLC. METHODS: The study was carried out in a population of 48 patients with advanced NSCLC which have received pemetrexed monotherapy in second and third line. RFC expression was assessed using a two-step model of immunohistochemical staining in paraffin-embedded tissue samples. RESULTS: RFC expression was detected in 16 (33 %) patients. In the global population, the median progression free survival (PFS) and the median overall survival (OS) were 3.3 and 6.5 months respectively. The subgroup of patients with expression of RFC had a tendency to better median PFS (4.5 vs 2.8 months; p = 0.926) and median OS (11.7 vs 4.8; p = 0.150). In patients with adenocarcinoma histology and RFC expression median OS after treatment with pemetrexed was 14.4 months versus 5.0 in those with adenocarcinoma but without RFC expression (p = 0.039). CONCLUSIONS: These results suggest the possible relation between RFC expression and response to treatment with antifolates (pemetrexed) independently of the tumor histology. Further studies are required to confirm these results.