Muhammad Furrukh

Tobacco smoking remains the most established cause of lung carcinogenesis and other disease processes. Over the last 50 years, tobacco refinement and the introduction of filters have brought a change in histology, and now adenocarcinoma has become the most prevalent subtype. Over the last decade, smoking also has emerged as a strong prognostic and predictive patient characteristic along with other variables. This article briefly reviews scientific facts about tobacco, and the process and molecular pathways involved in lung carcinogenesis in smokers and never-smokers. The evidence from randomised trials about tobacco smoking's impact on lung cancer outcomes is also reviewed.

BACKGROUND: Colorectal cancer is the most common gastrointestinal cancer in Oman with an increasing incidence. We here report the presenting features, treatment outcomes and survival in a University hospital in Oman and compare our data with regional and international studies. MATERIALS AND METHODS: Medical records of patients with colorectal cancer were reviewed retrospectively between June 2000 and December 2013 and were followed until June 2014. RESULTS: A total of 162 patients were diagnosed with colorectal cancer. The majority were males (58.6%), with a median age of 56 years. Rectum was involved in 29.6% of patients, followed by ascending and sigmoid colon. The majority of patients had stage III (42.6%) and stage IV (32.7%) disease at presentation. K-Ras status was checked for 79 patients, and 41 (51.9%) featured the wild type. Median relapse free survival was 22 months. Median overall survival for all patients was 43 months. Observed 5 year overall survival (OS) for stages I, II and III was 100%, 60% and 60% respectively. On Log rank univariate analysis, age, BMI, diabetes, hypertension, metformin use, stage, clinical nodal status for rectal cancer, pathological T and nodal status, site of metastasis, surgical intervention, chemotherapy, radiotherapy, chemotherapy regimen, no of cycles of chemotherapy, response, RFS, site of recurrence and administration of 2nd line chemotherapy were significant factors affecting OS. On Cox regression multivariate analysis none of the factors independently affected the OS. CONCLUSIONS: The majority of patients present with advanced disease and at young age. The survival rates are comparable to the published regional and international literature.

INTRODUCTION: Central venous catheters play an important role in the management of cancer patients. Different types of devices are associated with different patterns of complications. We report on the pattern of use and rate of complications of port-a-caths in patients diagnosed with malignant cancer at a single institution. METHODOLOGY: The data were collected retrospectively from patients who received the treatment for solid tumors or lymphoma through a port-a-cath at the Sultan Qaboos University Hospital (SQUH) between January 2007 and February 2013. RESULTS: A total of 117 port-a-caths were inserted in 106 patients. The majority (86; 73.5%) were implanted by an interventional radiologist, and the right internal jugular vein was accessed in 79 (67.5%) patients. Mean catheter indwelling time was 354 (range 3-1,876) days for all patients, 252 (3-1,876) and 389 days (13-1,139) for patients with and without complications, respectively. Thirty (25.6%) port-a-caths were removed prematurely, mainly due to infectious complications, while 17 (14.5%) were removed after completion of treatment. Staphylococcus aureus was the most frequently isolated organism, found in 8 (6.8%) patients. Underlying diagnosis (p < 0.001), chemotherapy regimen (p < 0.001), sensitivity to antibiotics (p = 0.01), and any complication (p < 0.001) were significant factors affecting the duration of port-a-cath use. None of these factors were significant on multivariate cox regression analysis. CONCLUSIONS: The mean duration of port-a-cath use was almost one year. Infection was the most common complication leading to premature removal, followed by port thrombosis.

Pulmonary adenocarcinoma is a common neoplasm, yet the one with enteric or intestinal differentiation poses a diagnostic challenge to pathologists as it shares a common immunohistochemical profile with metastatic colorectal carcinoma. We report a case of a 61-year-old woman. She was on surveillance when incidentally she was discovered to have multiple bilateral lung nodules on imaging; the largest was surgically removed for histological examination. Morphology was consistent with a moderately differentiated adenocarcinoma .The tumour cells were positive for cytokeratin (CK) 7, CDX2, CK20 and were negative for thyroid transcription factor 1. The morphology and immune histochemical profile raised the differential diagnosis of a metastatic colorectal carcinoma and a primary lung adenocarcinoma with enteric differentiation. On the basis of morphology and CK7 positivity we established the diagnosis of enteric-type adenocarcinoma of primary lung origin. She has completed planned courses of palliative chemotherapy and remains on surveillance.