Tratamiento quirúrgico de la enfermedad de Paget de la mama mediante técnica Grisotti. Descripción de un caso / Surgical management of Paget's disease of the breast using the Grisotti procedure. A case study

La afectación del complejo aréola-pezón (CAP) en la enfermedad de Paget está asociada en muchos casos a un carcinoma de mama subyacente. La rareza de la enfermedad hace que no se hayan establecido niveles de evidencia ni grados de recomendación concluyentes sobre el tipo de tratamiento quirúrgico de esta enfermedad. En la actualidad el tratamiento oncoplástico más radioterapia, en casos seleccionados, supone una alternativa a la indicación de mastectomía. Se presenta el caso de una paciente con enfermedad de Paget, y carcinoma intraductal subyacente, tratada con cirugía oncoplástica patrón de Grisotti seguida de radioterapia

The involvement of the nipple-areolar complex in Paget's disease is associated in many cases with an underlying breast cancer. The rarity of the disease means that no levels of evidence or conclusive grades of recommendation have been established concerning the type of surgical treatment of this disease. Nowadays, oncoplastic surgery plus radiotherapy, in selected cases, is an alternative to the indication of mastectomy. We present the case of a patient with Paget's disease, and underlying intraductal cancer treated with Grisotti's oncoplastic surgery procedure followed by radiotherapy

Cáncer de mama en mujeres muy jóvenes, nuestra experiencia / Breast cancer in very young women: Our experience

El cáncer de mama en mujeres jóvenes representa un grupo singular por su edad, diagnóstico, comportamiento tumoral, deseo genésico y pronóstico. Hemos realizado un estudio descriptivo retrospectivo entre 1995 y 2012 de 1.392 mujeres diagnosticadas en nuestro centro de cáncer de mama. Se seleccionó a 56 (4,02%) mujeres cuya edad al diagnóstico era <35 años. Se estudiaron diferentes variables como datos epidemiológicos, métodos diagnósticos, abordaje quirúrgico, resultados histológicos y tasa de supervivencia. Se realizó análisis estadístico con programa informático SPSS 15.0. La edad media fue de 31,83 + 2,92 (24-35) años. Existían antecedentes familiares de cáncer de mama en 11 (19,62%) pacientes. Una paciente había presentado previamente un cáncer de ovario (1,78%). Eran nulíparas 24 (42,85%) y 5 (8,92%) tuvieron una gestación tras el diagnóstico-tratamiento del cáncer de mama. Los hallazgos clínicos fueron la presencia de nódulos en 49 (87,5%). La ecografía mamaria fue indicada como 1.er método diagnóstico por imagen en 35 (62,5%) casos. El tratamiento neodyuvante fue de elección en 6 (10,70%). El tratamiento quirúrgico fue indicado inicialmente en 49 (87,5%). La cirugía conservadora pudo realizarse en 23 (41,07%). El tipo histólógico más frecuente fue el carcinoma ductal infiltrante en 41 (73,2%). Respecto al seguimiento, 31 (55,35%) pacientes continúan vivas y en remisión completa. El tratamiento del cáncer de mama en pacientes jóvenes debe individualizarse. Siempre que sea posible se recomendará la realización de cirugía conservadora (valorando la quimioterapia neoadyuvante para disminuir el tamaño tumoral) así como la cirugía oncoplástica, ya que pueden contribuir a mejorar la calidad de vida sin empeorar la supervivencia de dichas pacientes

Breast cancer in young women represents a unique group because of age, diagnosis, tumor behavior, associated infertility, and prognosis. We conducted a retrospective study between 1995 and 2012 in 1392 women diagnosed with breast cancer in our center. We selected 56 women (4.02%) whose age at diagnosis was < 35 years. Several variables, such as epidemiological data, diagnostic methods, the surgical approach, histological results, and the survival rate were studied. The statistical analysis was conducted with SPSS 15.0 software. The mean age was 31.83 + 2.92 (24-35) years. A family history of breast cancer was found in 11 (19.62%) patients. One patient had previously had ovarian cancer (1.78%). Twenty-four women (42.85%) were nulliparous and 5 (8.92%) became pregnant after diagnosis or treatment of breast cancer. Clinical findings consisted of the presence of nodules in 49 (87.5%). Breast ultrasound was indicated as the first imaging method in 35 (62.5%) women. Treatment consisted of neoadjuvant therapy in 6 (10.70%) patients. Surgical treatment was indicated initially in 49 (87.5%). Conservative surgery was performed in 23 (41.07%). The most common histological type was infiltrating ductal carcinoma in 41 (73.2%). A total of 31 (55.35%) patients are still alive and in complete remission. The treatment of breast cancer in young patients should be individualized. Whenever possible, conservative surgery should be performed (evaluating neoadjuvant chemotherapy to reduce tumor size), as well as oncoplastic surgery, as they can help improve quality of life without impairing survival in these patients

Complicaciones del parto natural no hospitalario en área rural de Gambo, Etiopía / Complications of natural childbirth in the non-hospital setting in a rural area of Gambo, Ethiopia

Hemos realizado una cooperación internacional con el Hospital de Gambo (Etiopía), en el área de ginecología y obstetricia. Ha consistido básicamente en la práctica de cirugía programada, seguimiento de pacientes hospitalizadas, consulta externa, ecografía y, sobre todo, atención de la urgencia obstétrica. Exponemos a continuación nuestra experiencia sobre la complejidad de los casos obstétricos asistidos en los cuales fue preciso realizar una histerectomía obstétrica

International cooperation was established with the Gambo Hospital, in the specialty of obstetrics and gynecology, basically consisting of elective surgery, follow-up of hospitalized patients, outpatient consultations, sonography, and-in particular- obstetric emergencies. We describe our experience of the complexity of obstetric emergencies that required hysterectomy

La enfermedad de Paget de la mama en nuestra área: revisión 1998-2012 / Paget disease of the breast in our setting: review 1998-2012

La enfermedad de Paget de la mama es una entidad poco frecuente y de buen pronóstico. El tratamiento clásico ha sido la mastectomía, pero es posible una cirugía conservadora de la mama, y hoy en día debe valorarse como primera opción siempre y cuando se aseguren márgenes libres con un resultado estético aceptable. Las pruebas de imagen son fundamentales para descartar un carcinoma subyacente y de cara a la planificación de una cirugía conservadora, así como para el futuro seguimiento de estas pacientes

Paget disease of the breast is a relatively rare entity with a favourable prognosis. Form any years, the gold standard treatment has been mastectomy. However, breast-conserving surgery is now feasible and should be evaluated as the first-line option whenever negative margins with acceptable cosmetic results can be achieved. Imaging techniques are essential to exclude an underlying carcinoma and play an important role in selecting candidates for breast-conserving treatment and in follow-up

Stability of nematic and smectic phases in rod-like mesogens with orientation-dependent attractive interactions.

The stability of isotropic (I), nematic (N), smectic A (Sm A), and hexatic (Hex) liquid crystalline phases is studied for a fluid of molecules with a rod-like shape and dispersive interactions dependent on orientation. The fluid is modeled with the spherocylindrical Gay-Berne-Kihara interaction potential proposed in a recent work, with parameters favoring parallel pair orientations. The liquid crystal phase diagram is characterized for different molecular aspect ratios by means of Monte Carlo simulations in the isobaric-isothermal ensemble. Three types of triple points are observed, namely, I-Sm A-Hex, I-N-Sm A, and N-Sm A-Hex, leading to island-shape domains for the smectic A phase. The resulting phase diagrams are compared with those derived previously for prolate fluids of ellipsoidal and spherocylindrical symmetry. It is concluded that the stability of the layered phases with respect to the nematic phase is enhanced in the spherocylindrical fluids due to geometrical constraints. Furthermore, the anisotropy of the dispersive interactions induces a stronger dependence of the overall phase diagram on temperature and aids in the energetic stabilization of the hexatic crystalline phase with respect to the fluid smectic A phase.

Layering in sedimentation of suspensions of charged colloids: simulation and theory.

We study the equilibrium sediment of a multicomponent system of charged colloids using primitive model Monte Carlo simulations, which include counterions explicitly. We find separation of the different colloidal components into almost pure layers, where colloids with large charge-to-mass ratio sediment higher in the sample. This effect appears due to a competition between ionic entropy, gravitational energy, and electrostatic energy. Our simulations provide a direct confirmation of recent theoretical predictions on the sedimentation of multicomponent mixtures of charged colloids in regimes with relatively low total densities and low colloidal charges. To explore the limitations of the theory we perform simulations at higher total densities for monodisperse and multicomponent systems and at stronger electrostatic couplings by increasing the colloidal charge for monodisperse suspensions. We find good agreement between theory and simulation when the colloidal charge is increased in the monodisperse case. However, we find deviations between simulations and theory upon increasing the total densities in the monodisperse and multicomponent systems. The density profiles obtained from simulations are more homogeneous than those predicted by theory. The spontaneous formation of layered structures predicted by the theory and found by simulation can serve as a useful tool to separate different components from a mixture of charged colloids.

A novel orientation-dependent potential model for prolate mesogens.

An intermolecular potential is introduced for the study of molecular mesogenic fluids. The model combines distinct features of the well-known Gay-Berne and Kihara potentials by incorporating dispersive interactions dependent on the relative pair orientation to a spherocylinder molecular core. Results of a Monte Carlo simulation study focused on the liquid crystal phases exhibited by the model fluid are presented. For the chosen potential parameters, molecular aspect ratio L*=5 and temperatures T*=2, 3, and 5, isotropic, nematic, smectic-A, and hexatic phases are found. The location of the phase boundaries as well as the equation of state of the fluid and further thermodynamical and structural parameters are discussed and contrasted to the Kihara fluid. In comparison to this latter fluid, the model induces the formation of ordered liquid crystalline phases at lower packing fractions and it favors, in particular, the appearance of layered hexatic ordering as a consequence of the greater attractive interaction assigned to the parallel side-to-side molecular pair configurations. The results contribute to the evaluation of the role of specific interaction energies in the mesogenic behavior of prolate molecular liquids in dense environments.

Parsons-Lee and Monte Carlo study of soft repulsive nematogens.

A general approach based on the Parsons-Lee theory for soft repulsive molecular fluids is employed to investigate the nematogenic behavior of prolate thermotropic liquid crystals over a broad temperature range. The theory is solved for the particular case of the Kihara soft repulsive spherocylinder model, which is mapped into an effective hard core interaction with a temperature-dependent molecular diameter, expected to resemble the average size and shape of the soft molecules at a given temperature. The reduction of the effective molecular diameter with temperature in the Kihara soft repulsive fluid implies implicitly an increase of the elongation of the molecule and induces the stabilization of the nematic phase at smaller effective packing fractions, contrary to what is found for other fluid models. The rationalization of this effect in terms of excluded volume steric arguments is corroborated by the good general agreement between the Parsons-Lee approach and Monte Carlo simulations for the equation of state of the fluid in the vicinity of the isotropic-nematic transition.

Crowding effects in binary mixtures of rod-like and spherical particles.

Crowding effects relevant to the phase stability of binary mixtures of rod-like and spherical particles are investigated by means of Monte Carlo simulations in the isobaric NPT ensemble. The two types of particles are represented, respectively, by freely rotating hard spherocylinders of a moderate aspect ratio (L/sigma = 5) and hard spheres of the same diameter sigma. Molar fractions of spheres ranging xHS = 0.00-0.37 are considered with the aim of characterizing the crowding effects on the liquid crystal phases of the hard spherocylinder fluid induced by the spherical component as depleting agent. We find that the addition of the spherical crowder is beneficial for the stabilization of the layers of the rod-like particles characteristic of the smectic phase. On the contrary, the addition of spheres has a negative impact upon the stability of the nematic phase, where the rod-like particles tend to align collectively parallel to each other. Interestingly, the spheres tend to arrange forming rod-like clusters in the nematic phase and lamellar structures in the smectic phase, which is compensated by the entropy gained by the spherocylinder particles in each phase. The main results are in qualitative agreement with recent experimental and theoretical studies and serve to test the prediction of current equations of state for these types of binary mixtures.

Liquid crystal behavior of the Kihara fluid.

The liquid crystal phases of the Kihara fluid have been studied in computer simulations. The work focuses on the isotropic-nematic-smectic-A triple point region, especially relevant for the understanding of the properties and the design of real mesogens with specific phase diagrams. The Kihara interaction resembles more appropriately than other related models, the shape of elongated polymers and biomolecules, and a closer assertion is provided for the role of the configurational entropy and the dispersive interactions in the behavior of such molecules in dense phases or under macromolecular crowding conditions.

Solution of the Percus-Yevick equation for square well spherocylinders.

The Percus-Yevick equation for square-well spherocylinders has been numerically solved for some selected orientations following a methodology proposed previously for different fluids of elongated molecules. The equation is solved for particles of aspect ratios ranging from L/sigma=0.3 up to L/sigma=5.0, attractive range lambda/sigma=1.5, and packing fractions within eta=0.1-0.3. The resulting pair correlation functions are checked against isothermal-isobaric Monte Carlo simulations and good agreement is found for the short-range structure, at intermolecular distances within one molecular diameter sigma to contact for each of the selected orientations. At larger distances, the integral equation tends to overestimate the pair correlations. The results confirm the prediction of reference-system average Mayer-function perturbation theory for short aspect ratios, reaching the Onsager limit for the greater aspect ratios. Some instabilities of the solution for the longest models and higher densities are tentatively discussed in terms of their possible relation to frustration phenomena found in some polymer and complex systems.