Expression of Cytochrome P450 Enzymes in Pediatric Non-Rhabdomyosarcoma Soft Tissue Sarcomas: Possible Role in Carcinogenesis and Treatment Response

The 5-year relative survival rate estimate of treated patients with non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) is ∼50% since they generally present with tumor progression, relapse, metastasis, and/or chemoresistance. The expression of cytochrome P450 (CYP) enzymes in malignancies can affect the pharmacology of drugs commonly used in chemotherapy or confer susceptibility to development of chemical carcinogenesis; in addition, their specific tumor expression can be used as a therapeutic target. Using qPCR and Western blot assays, the expression of CYP1B1, CYP2E1, CYP3A4, and CYP3A5 were analyzed in a cohort of tumor tissue paired with non-malignant adjacent tissue of patients with NRSTS. The mRNA and protein expression of CYP1B1, CYP2E1, and CYP3A4 were significantly increased in tumor tissue. We propose that the expression of these isoforms is related to carcinogenesis and chemoresistance frequently observed in these neoplasms.

Academic paediatric surgery and work-life balance: Insights from Mexico

Academic pediatric surgery in Mexico has many challenges and opportunities. Work life balance, health service delivery and committements to our many students and residents must be tailored to goals and aspirations respecting talent at every opportunity when we encounter it. This article offers a perspective on the landscape and how we can shape the future in our nation to embrace new leadership in academic pediatric surgery.

MDR1 not CYP3A4 gene expression is the predominant mechanism of innate drug resistance in pediatric soft tissue sarcoma patients

BACKGROUND

Intratumoral up-regulation of genes coding for drug transporters and metabolizing enzymes, such as MDR1 and CYP3A4, after chemotherapy are linked to cancer drug resistance. However their expression in primary soft tissue sarcomas (STS) prior to drug treatment and their role in innate resistance remain unclear.

OBJECTIVE

The aim of this study was characterize MDR1 and CYP3A4 expression pattern before to chemotherapy and its clinical implication in pediatric STS.

METHODS

In this prospective study we analyzed MDR1 and CYP3A4 mRNA expression in both normal and tumor tissues from 28 newly diagnosed STS pediatric and then compared with patients' clinical-pathological data, including chemotherapy response.

RESULTS

Our data showed that the expression of the MDR1 gene was significantly higher in malignant tissue than in the normal tissues of patients with STS. In addition, high MDR1 expression was significantly associated with local advances, as well as poor response to treatment. In contrast, CYP3A4 expression level was negligible in both tumoral and non-tumoral tissues.

CONCLUSIONS

These results suggest that a significant mRNA level of MDR1 gene was intrinsically present in STS before exposure to chemotherapeutic drugs, suggesting that MDR1 may be important contributors of innate chemoresistance of this tumor type.

Delivery of Pediatric Cancer Care in Mexico: A National Survey

Purpose Limited data describe the delivery of pediatric cancer care in Mexico. We report a nationwide survey of pediatric cancer units. Methods An electronic survey was distributed to 74 pediatric cancer units in Mexico to describe case volumes; organization of care; and availability of medical/surgical specialists, supportive care, complex therapies, and diagnostic services. Centers were classified as low (< 30 new patients/year), medium (30 to 59/year) and high (≥ 60/year). Results Sixty-two centers completed the survey (response rate, 84%). The median annual new case volume per center was 50 (interquartile range [IQR], 23 to 81). Thirty-four percent (n = 21), 26% (n = 16), and 40% (n = 25) of units were low-, medium-, and high-volume centers, respectively. Treatment units reported a median of two pediatric oncologists (IQR, 2) and one pediatric hematologist (IQR, 1 to 2). Availability of medical and surgical subspecialists varied by center size, with substantially more specialist support at higher-volume centers ( P < .01). Multidisciplinary tumor boards are available at 29% (six of 21), 56% (nine of 16), and 76% (19 of 25) of low- to high-volume centers, respectively ( P = .005). Radiation and palliative care services are available at 42% (n = 26) and 63% (n = 36) of all centers, which did not vary by center volume. Educational support for hospitalized children and school reintegration programs are available at 56% (n = 36) and 58% (n = 36) of centers, respectively. One third (38% [n = 23]) of centers reported that at least one half of patients were lost to follow-up during the transition from pediatric to adult programs. Conclusion A large variation exists in annual case volumes across Mexican pediatric cancer centers. Additional efforts to increase access to multidisciplinary, supportive, and palliative care across all pediatric cancer units in Mexico are required.

The burden of childhood cancer in Mexico: Implications for low- and middle-income countries

In Mexico, childhood cancer incidence and mortality have increased in the last decade. Through government actions since 2005, the Popular Medical Insurance (PMI) program for childhood cancer was created. The objective of PMI was to offer early cancer diagnosis, standardized treatment regimens, and numerous pediatric oncology residency programs. It has also accredited 55 national hospitals for the care of these children. Current problems still present under the PMI include shortage of pediatric oncologists and nurses and high rate of abandonment of treatment. Our aim is to describe the current scenario of childhood cancer care in Mexico, especially from the perspective of the PMI and how it has impacted human resources, infrastructure, and medical education.

Tumor neuroectodérmico primitivo primario de páncreas en un paciente pediátrico. Reporte de caso y revisión de la literatura

<p>Los tumores neuroectodérmicos primitivos son tumores de células pequeñas y redondas derivadas del tejido blando, pertenecen a la familia del sarcoma de Ewing. El tumor neuroectodérmico primario del páncreas es muy poco frecuente, en la literatura sólo se han reportado 17 casos. Reportamos el caso de una paciente de 9 años de edad, con diagnóstico de tumor neuroectodérmico primario del páncreas a la que se le realizó una cirugía de Whipple e inició tratamiento de quimioterapia con ciclofosfamida, vincristina, doxorrubicina pegilada, etopósido e ifosfamida y radioterapia. Desde marzo de 2013 la paciente se encuentra en vigilancia, con un periodo de seguimiento de 23 meses. Actualmente, se encuentra en buenas condiciones generales y sin evidencia de actividad tumoral.</p>

Descriptive Epidemiology in Mexican children with cancer under an open national public health insurance program

Background

All the children registered at the National Council for the Prevention and Treatment of Childhood Cancer were analyzed. The rationale for this Federal Government Council is to financially support the treatment of all children registered into this system. All patients are within a network of 55 public certified hospitals nationwide.

Methods

In the current study, data from 2007 to 2012 are presented for all patients (0–18 years) with a pathological diagnosis of leukemia, lymphoma and solid tumors. The parameters analyzed were prevalence, incidence, mortality, and abandonment rate.

Results

A diagnosis of cancer was documented in 14,178 children. The incidence was of 156.9/million/year (2012). The median age was 4.9. The most common childhood cancer is leukemia, which occurs in 49.8% of patients (2007–2012); and has an incidence rate of 78.1/million/year (2012). The national mortality rate was 5.3/100,000 in 2012, however in the group between 15 to 18 years it reaches a level of 8.6.

Conclusions

The study demonstrates that there is a high incidence of childhood cancer in Mexico. In particular, the results reveal an elevated incidence and prevalence of leukemia especially from 0 to 4 years. Only 4.7% of these patients abandoned treatment. The clinical outcome for all of the children studied improved since the establishment of this national program.

Hepatoblastoma. Clinical experience at a single institution using the Siopel staging system

BACKGROUND

Staging in Hepatoblastoma has recently become controversial. In developing countries diagnosis occurs mostly in advanced stages under these circumstances, we propose another option that can be considered of prognostic value.

METHOD

A retrospective analysis of cases diagnosed with Hepatoblastoma (HB), treated in a single Institution, in nine years was conducted. Chemotherapeutic regimens were analyzed, as well as the number of courses administered and response to treatment.

RESULTS

Thirty-two patients were studied. Patients had symptoms from 1 to 25 weeks before diagnosis. SIOP stratification was used, finding 12 cases in PRETEXT II, 6 cases in PRETEXT III, and 14 cases in PRETEXT IV. No single case was identified in PRETEXT I.

CONCLUSIONS

When comparing survival using the PRETEXT system, SIOP and our study showed marked differences. These results may not be comparable due to differences in tumor volume among the same PRETEXT stratification. We believe that tumor volume is related to prognosis.