Intraosseous Schwannoma of fibula: A case report.

Schwannoma, also called neurilemomma is a benign neoplasm. It originates from Schwann cells which are involved in myelination of peripheral nerves and commonly occur in the soft tissues of the head and neck. Intraosseous schwannoma is rare and accounts for only 0.2% of overall primary bone tumours. Merely 200 cases have been reported in the literature. Intraosseous schwannoma of long bones is even rarer, amounting for only 20 cases reported. We present a case of intraosseous Schwannoma in the distal shaft of the fibula, in an 18-year-old female patient who presented with pain in the right leg for 2 years. MRI showed a lytic lesion, with a differential diagnosis of aneurysmal bone cyst. The tumour was excised and on histopathological examination, a diagnosis of intraosseous schwannoma was made.

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.

How our practice of histopathology, especially tumour pathology has changed in the last two decades: reflections from a major referral center in Pakistan.

Continued advances in the field of histo-pathology (and cyto-pathology) over the past two decades have resulted in dramatic changes in the manner in which these disciplines are now practiced. This is especially true in the setting of a large university hospital where the role of pathologists as clinicians (diagnosticians), undergraduate and postgraduate educators, and researchers has evolved considerably. The world around us has changed significantly during this period bringing about a considerable change in our lifestyles and the way we live. This is the world of the internet and the world-wide web, the world of Google and Wikipedia, of Youtube and Facebook where anyone can obtain any information one desires at the push of a button. The practice of histo (and cyto) pathology has also evolved in line with these changes. For those practicing this discipline in a poor, developing country these changes have been breathtaking. This is an attempt to document these changes as experienced by histo (and cyto) pathologists practicing in the biggest center for Histopathology in Pakistan, a developing country in South Asia with a large (180 million) and ever growing population. The Section of Histopathology, Department of Pathology and Microbiology at the Aga Khan University Hospital (AKUH) in Karachi, Pakistan's largest city has since its inception in the mid-1980s transformed the way histopathology is practiced in Pakistan by incorporating modern methods and rescuing histopathology in Pakistan from the primitive and outdated groove in which it was stuck for decades. It set histopathology in Pakistan firmly on the path of modernity and change which are essential for better patient management and care through accurate and complete diagnosis and more recently prognostic and predictive information as well.

Oligodendroglioma arising in the glial component of ovarian teratomas: a series of six cases and review of literature.

AIMS: To report the exceedingly rare occurrence of oligodendroglioma in the glial component of ovarian teratomas. METHODS: Six cases of oligodendrogliomas arising in the glial component of ovarian teratomas were studied and the literature was reviewed. Immunohistochemistry was performed by the Flex technique. RESULTS: The ages of the patients ranged from 12 to 28 years (mean 21 years). Four tumours were located in the right and one in the left ovary. The size of the ovarian cysts ranged from 7 cm to 29 cm (mean 19.6 cm). Four cases arose in immature and two cases in mature teratomas. In all cases, oligodendroglioma was WHO grade II. On immunohistochemistry, glial fibrillary acidic protein stain was positive in all cases. The Mib 1 (Ki 67) proliferative index was low and the tumour cells were negative for synaptophysin. Follow-up was available in five patients and ranged from 1 to 42 months. Two patients died of disease after 1 and 36 months of diagnosis, respectively. In both these cases oligodendroglioma arose in an immature teratoma. The remaining three patients are alive with a follow-up of 4-42 months. CONCLUSIONS: Oligodendroglioma arising in the glial component of ovarian teratomas is exceedingly rare. Ovarian teratomas should be extensively sampled and carefully evaluated to rule out the possibility of a glial tumour. This is the single and largest series of oligodendrogliomas arising in ovarian teratomas. The prognosis is good for oligodendrogliomas arising in mature teratomas compared with those arising in immature teratomas, although long-term follow-up is needed to determine the exact behaviour.

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.

Angiokeratoma of tongue: a series of 14 cases.

Angiokeratomas (AC) are vascular lesions which are defined histologically as one or more dilated blood vessels lying directly subepidermal and showing an epidermal proliferative reaction with ectatic capillaries in the papillary dermis. Only three other cases of isolated mucosal angiokeratoma have been reported in the indexed literature. We reviewed all cases of angiokeratoma located on the tongue, diagnosed in our department during a study period of 10 years (1995-2005). Histologically all 14 cases showed dilated and congested blood vessels in the upper papillary dermis. They lack deep dermal involvement. Hyperkeratosis and acanthosis were also seen in most of the cases. No clinical data was available to assess systemic disease. A higher incidence of of AC in tongue is seen in our study.

Analysis of cervical smears in a Muslim population.

BACKGROUND: Screening for cancer of the cervix remains a neglected health care issue in Pakistan. To provide baseline data for future efforts to improve screening, we conducted a retrospective analysis of cervical smears taken in the obstetrics and gynaecological clinics of the Aga Khan University Hospital, Karachi, Pakistan. METHOD: We collected data on cervical smear cytology for cervical smears taken from January 1, 1990 to December 31, 1996. We assessed risk factors for dysplasia, including age, age at first marriage, and number of pregnancies. RESULTS: The overall prevalence of abnormal smears in our study was 0.5%. Of 20,995 cervical smears, 12,451 (59.3%) smears showed non-specific inflammation, 7302 (34.8%) were reported as normal, 809 (3.85%) showed monillial infection, 148 (0.71%) showed atypia, 105 (0.5%) had dysplastic cytology, and 52 (0.25%) samples were inadequate. The highest incidence of dysplastic smears was seen in the age group 35 to 44 years. Of 105 patients with dysplasia, 12 were pregnant, and all were asymptomatic, while in 93 non-pregnant women, 33 were symptomatic. CONCLUSION: The low prevalence of abnormal smears, compared with data from Western populations, could be due to the inherent bias of health awareness in the women who attended our hospital. The results of this study may serve as a baseline for future comparisons. A larger community-based study may establish the exact prevalence of malignant and premalignant lesions so as to plan for future screening.

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.