Molecular and radiological characterization of glioblastoma multiforme using magnetic resonance imaging.

BACKGROUND: Glioblastoma multiforme (GBM) is the most malignant, aggressive and common form of primary brain cancer. Currently, GBM is considered to be a homogenous mass as all its margins are treated equally at the time of resection. However, it is not known whether radiologically distinct regions of GBM are also distinct at molecular level. We conducted this study to see if radiologically distinct regions were also different at the molecular level. METHODS: In 20 patients, MRI derived variance known as Apparent Diffusion Coefficient (ADC) was plotted against Contrast Enhancement (CE). Four radiologically distinct regions were identified: 1) high ADC and low CE; 2) low ADC and low CE; 3) high ADC and high CE; and 4) low ADC and high CE. Biopsy samples were collected from these four regions of interest in each patient and immunohistochemistry was conducted to characterize cellular features and identify oncogene and stem cell marker expressing cells. RESULTS: Markedly increased nuclear pleomorphism, cellularity and necrosis were seen in region 2. Oncogene IDH was expressed in all regions, however, it was highest in region 4. Stem cell marker, CD44 expression was highest in region 1 and lowest in region 2 and 3. The expression of CD133 was highest in region 3. CONCLUSIONS: This study shows that ADC/CE plot can divide GBM into four regions, whose heterogeneity is evidenced by differential expression of nuclear pleomorphism, necrosis, cellularity and mitotic rate as well as the expression of oncogene and stem cell markers.

Spectrum of malignancy in mixed tumors of salivary gland: a morphological and immunohistochemical review of 23 cases.

Malignancy arising in mixed tumors of the salivary gland is a distinct entity that can occur sporadically or in association with a background of pleomorphic adenoma. Carcinoma arising with a background of pleomorphic adenoma is well documented. However, there are rare occurrences of aggressive de novo carcinosarcomas of the parotid that have been reported. Various cell lineages such as the epithelial glandular cells and the stromal spindle cells are involved. We report 23 cases of tumors of the salivary gland comprising 18 cases of carcinoma ex pleomorphic adenoma, four cases of carcinosarcoma of the parotid and one case of benign metastasizing pleomorphic adenoma. The occurrence of various malignancies suggests that this phenomenon is not very uncommon and should be looked for when reporting a mixed tumor.

Frequency of primary solid malignant neoplasms in both sexes, as seen in our practice.

BACKGROUND: To determine the frequency of various histologic types of primary solid malignant neoplasms in males and females, in our practice, in a large series of surgical biopsies. METHODS: A retrospective study of 20,000 consecutive surgical biopsies in the section of Histopathology, Aga Khan University Hospital (AKU), Karachi, in 2004. RESULTS: Squamous cell carcinoma of oral cavity was the commonest malignant neoplasm in males followed by diffuse Large B cell, Non-Hodgkin's lymphoma and Prostatic adenocarcinoma. In females, infiltrating Ductal carcinoma of the breast was overwhelmingly the commonest malignant neoplasm followed by Squamous cell carcinoma of the oral cavity and esophagus. CONCLUSION: Out of 20,000 biopsies, there were 4616 (23.08%) malignant neoplsms. Carcinoma of oral cavity is very common in our population in both sexes.

Frequency of primary solid malignant neoplasms in different age groups as seen in our practice.

BACKGROUND: To determine in a large series of surgical biopsies, the frequency of various histologic types of primary solid malignant neoplasms in males and females in different age groups. METHODS: A retrospective study of 20,000 consecutive surgical biopsies reposted in the section of histopathology, AKU in 2004. RESULTS: Malignant neoplasms are commonest in the fifth and sixth decades of life. The commonest malignant neoplasms in the first decade were Hodgkin's lymphoma and Wilm's tumor in males and females respectively. In the second decade, osteosarcoma in males and Ewing's sarcoma / PNET in females. In the third decade, colorectal adenocarcinoma in males and infiltrating. Ductal carcinoma of breast in females. In the fourth decade, squamous cell carcinoma of oral cavity in males and infiltrating ductal carcinoma of breast in females. In the fifth decade squamous cell carcinoma of oral cavity in males and infiltrating ductal carcinoma of breast in females. In sixth decade, squamous cell carcinoma of oral cavity in males and infiltrating ductal carcinoma of breast in females and in the seventh decade, prostatic adenocarcinoma in males and infiltrating ductal carcinoma of the breast in females. Above age of 70 years, the commonest malignant were again prostatic adenocarcinoma in males and infiltrating ductal carcinoma of breast in females. CONCLUSION: Malignant neoplasms are commonest in the fourth, fifth and sixth decades of life.

Renal cortical necrosis: a case series of nine patients & review of literature.

BACKGROUND: The purpose of this study is to review cases of renal cortical necrosis (RCN) which we came across during a period of five years, confirmed on needle biopsy specimens, with literature available so far. METHODS: All renal biopsy records between January 1996 to December 2001 at the Aga Khan University Hospital, Karachi, Pakistan were reviewed to identify patients with histologically proven renal cortical necrosis. Seven patients were also referred by the department of Nephrology, Lady Reading Hospital, Peshawar, Pakistan. Patients' medical records were reviewed for demographic, clinical, and follow up data. RESULTS: There were total of nine patients identified with renal cortical necrosis. The mean age was 26.21 +/- 13.01 year. Five cases (55.5%) were caused by obstetric complications. The most common histology type of RCN was patchy cortical necrosis in seven patients (77.8%). Three patients were alive at last follow up; remaining patients were lost to follow up. CONCLUSION: Obstetric complications remain the leading cause of renal cortical necrosis in our setting. The recognition of this entity and value of renal biopsy in cases of acute renal failure needs to be emphasized as this helps in establishing diagnosis, to assess prognosis and to aid in selection of a rational approach to therapy.