Primary gastric yolk sac tumour

Primary gastric yolk tumours are extremely rare. We report a 52-year-old male who presented to the Sultan Qaboos University Hospital, Muscat, Oman, in 2017 after having undergone a gastrectomy abroad due to a suspected poorly-differentiated adenocarcinoma. The patient subsequently returned to Oman to receive chemotherapy. However, while undergoing chemotherapy, an abdominal computed tomography scan revealed a lobulated mesenteric mass. Microscopic examination of the resected lesion confirmed a diagnosis of a yolk sac tumour. The mass was diffusely positive for á-fetoprotein [AFP] and a gastric carcinoma stain was negative. Gastrectomy slides from the patient's previous surgery were examined retrospectively. The morphology was typical for a yolk sac tumour and was negative for epithelial markers. An AFP stain showed diffuse immunoreactivity. Thus, the patient was deemed to have had a primary gastric yolk sac tumour which had later metastasised to the mesocolon. Germ cell tumour protocols were initiated and the patient responded well to treatment

Soft tissue rosai-dorfman disease case report

Rosai-Dorfman disease [RDD] is a rare benign proliferative histiocytic disorder characterised by massive lymphadenopathy. While extranodal involvement can occur in generalised RDD, isolated soft tissue RDD [STRDD] is extremely rare. We report a 17-year-old male patient who presented to the maxillofacial outpatient department of the Sultan Qaboos Hospital, Salalah, Oman, in 2015 with a painless cheek mass which had been slowly growing over the previous two months. Routine histopathological examinations and immunohistochemistry confirmed a diagnosis of STRDD. Currently, surgical excision is considered to be the most effective curative treatment for STRDD, as the outcomes of other treatment modalities are still unknown. Despite its rarity, STRDD should be considered in the differential diagnosis of histiocytic soft tissue lesions

Histomorphological spectrum of papillary carcinoma of thyroid in oman

Thyroid cancer is the commonest endocrine malignancy and is the second most common cancer affecting young females in Oman. The diagnosis of Papillary Thyroid Carcinoma [PTC] is based primarily on histologic architecture and nuclear morphology in routine Haematoxilin and Eosin [H and E] stained slides. Whenever in doubt, immunohistochemistry may be helpful. This retrospective study included 115 cases of PTC diagnosed at a tertiary care center in Oman over 10 years period, from 2001 to 2010. Slides and blocks of these cases were retrieved from the pathology laboratory. Ninety five [95] were females and 20 were males. Papillary Thyroid Carcinoma [PTC]was most commonly seen in the 20 - 50 years of age. The commonest morphologic variant seen in this population was classical papillary variant in 44/115 [38%] followed by papillary micro-carcinoma [n=30/115, 26%] and follicular variant of papillary carcinoma [n=18/115, 15.6%]. Out of the 30 micro-carcinoma cases, 18 were diagnosed incidentally in thyroids operated for multi-nodular goiter. Immunohistochemical marker CK-19 was positive in 29/31, HBME-1 and HMW-CK in 15/15 cases; CEA was in one case where it was reported negative. Immunohistochemical stains were useful in cases with atypical /doubtful morphology

p53 mutation/deletion profile in a small cohort of the Omani population with diffuse large B-cell lymphoma

Mutations/deletions affecting the TP53 gene are considered an independent marker predicting a poor prognosis for patients with diffuse large B-cell lymphoma [DLBCL]. A cohort within a genetically isolated population was investigated for p53 mutation/deletion status. Deoxyribonucleic acid [DNA] samples were extracted from 23 paraffin-embedded blocks obtained from DLBCL patients, and subjected to polymerase chain reaction [PCR] amplification and sequencing of exons 4-9 of the p53 gene. While 35% of patients analysed displayed allelic deletions [P <0.01], immunohistochemical analysis revealed a mutation rate of 69.5%. It is noteworthy that the rate of p53 mutations/deletions in this small cohort was found to be higher than that previously reported in the literature. Interestingly, patients with p53 mutations displayed a better overall survival when compared to those without. The survival of patients treated with rituximab-containing combination chemotherapy was significantly better than those who did not receive rituximab [P <0.05]. Furthermore, a modelling analysis of the deleted form of p53 revealed a huge structural change affecting the DNA-binding domain. The TP53 mutation/deletion status plays a role in mechanism[s] ruling the pathogenesis of DLBCL and may be useful for stratifying patients into distinct prognostic subsets

Myelomatous pleural effusion. Case report and review of the literature

Plasma cell myeloma is an uncommon disease which, besides primarily involving the bone marrow, has a tendency to involve other organs thus presenting with different clinical manifestations. While pleural effusions are infrequent in this disease, true myelomatous pleural effusions are extremely rare. We report the case of a middle-aged Omani man with relapsed plasma cell myeloma who developed bilateral pleural effusions. The diagnosis of myelomatous pleural effusion was made by finding many abnormal plasma cells as well as a high level of a monoclonal protein [IgG k] in the pleural fluid. In spite of a good initial response to therapy, the patient had progressive disease and died 6 months later with bacterial sepsis. We present a review of the literature that indicates the rarity of such a manifestation and its association with poor prognosis and short survival