Tumor cell and microvessel densities during the growth of a brain tumor: A theoretical study

Mathematical model for the tumor growth incorporating energy supply and requirement, angiogenesis efficiency and effect of elasticity of adjacent normal tissue to understand tumor biology and predict saturation status is rare to find. This study is conducted to address these issues. We propose mathematical expressions to explain alterations of tumor cell density (nT), microvessel density (MVD), and growth rate(r) during the development of brain tumors. We assume that nT increases during the growth of the tumor due to the increase of external pressure from the initial cell density (nT0); nT0 is same as the external normal tissue. The rate of increase in tumor cells (dNT/dt) depends on the rate of energy available for the creation of new cells and the energy required for a single cell division(?). Due to the increase of tumor cell density, hypoxia is developed, which up-regulates the secretion of vascular endothelial growth factor (VEGF) and new capillaries are generated. Therefore, the surface area density of capillaries (Acs) in tumors increases. Hence, we consider that Acs(t) ? nT(t). A modified logistic equation is developed. Temporal variations of nT(t), Acs(t), r(t) and tumor cell population ‘NT(t)’ are examined. The expressions of saturated cell density(nTM), saturated microvessel surface area density (AcsM) and tumor saturation time(Ts) are formulated. An important feature, tumor saturation factor ‘fTS’ is determined. When fTS<1, a tumor will saturate at Ts, and nTM depends solely on fTS.

Myeloid sarcoma: an uncommon presentation of myeloid neoplasms; a case series of 4 rare cases reported in a tertiary care institute

Myeloid sarcoma (MS) is a rare extramedullary neoplasm of myeloid cells, which can arise before, concurrently with, or following hematolymphoid malignancies. We report 04 such cases of MS, diagnosed in this institute over a period of 6 years, during various phases of their respective myeloid neoplasms/leukemias. These cases include MS occurring as a relapse of AML (Case 1), MS occurring as an initial presentation of CML (Case 2), MS occurring during ongoing chemotherapy in APML (Case 3), and MS presenting as a progression of MDS to AML (Case 4). In the absence of relevant clinical history and unemployment of appropriate immunohistochemical (IHC) studies, these cases have a high risk of being frequently misdiagnosed either as Non-Hodgkin's Lymphoma (NHL) or small round cell tumors or undifferentiated carcinomas, which may further delay their management, making an already bad prognosis worse. This case series has been designed to throw light on the varied presentation of MS and the lineage differentiation of its neoplastic cells through the application of relevant IHC markers along with their clinical correlation.

Sclerosing angiomatoid nodular transformation of spleen masquerading as a splenic abscess.

Here we report an incidental case of sclerosing angiomatoid nodular transformation (SANT) in an open splenectomy specimen from a young man who presented with insidious abdominal pain. The condition was mimicking as a splenic abscess. Histopathological and immunohistochemical analysis confi rmed this to be SANT. SANT presents a diagnostic challenge to clinicians, radiologists, as well as pathologists because of its extreme rarity. Therefore, it must be included as a differential diagnosis in cases with nonspecifi c pain or radiological splenic mass. This case highlights that SANT can present with varied clinical features and at a wide range of ages. A high index of suspicion is required for its diagnosis.