Perivascular epithelioid cell tumors (PEComas) are a family of rare mesenchymal tumors with discrete histological and immunohistochemical characteristics. Even rarer among them are cutaneous and subcutaneous PEComas. We describe a 34-year-old woman who presented with a large anterior abdominal subcutaneous lesion showing intact overlying skin and no obvious invasion of the abdominal musculature. A wide local excision was performed. Histopathology revealed a solitary tumor measuring 75 × 55 × 90 mm with epithelioid cells in nests with thin fibrovascular septa and spindle cells. Resection margins were clear with no invasion to the skin or rectus sheath. Tumor cells were positive for HMB-45 but negative for other markers. This is the largest subcutaneous PEComa reported to date.
Fifty-nine cases of tuberculous cervical lymphadenitis were analysed histologically. Characteristic epithelioid cell granulomas were seen in all the cases with central areas of caseation necrosis in 96.6% (57/59) of these cases. The diagnosis of tuberculosis was further established by the demonstration of acid-fast bacilli (AFB) in the tissue sections in 29 cases. These AFB, although occasional, were found more frequently within the epithelioid cells as compared with other zones of the granuloma. There was no significant association between necrosis and bacillary content. We conclude that light microscopical assessment is still a useful screening method to diagnose tuberculosis in cases of cervical lymphadenopathy.
Intramuscular shoulder angiomyolipomas are very rare. We report a case in a 22-year-old male with a well circumscribed lesion located on the back of the shoulder. This lesion, differs from renal angiomyolipoma in terms of non-association with tuberous sclerosis, circumscription and male predominance. Another characteristic feature is the absence of epithelioid cells. Differential diagnosis includes lipoma, angiolipoma, angioleiomyoma, hemangioma, myolipoma and liposarcoma. It is distinguished from the above mentioned entities by the presence of a combination of thick-walled blood vessels, smooth muscle and fat.
Intramuscular shoulder angiomyolipomas are very rare. We report a case in a 22-year-old male with a well circumscribed lesion located on the back of the shoulder. This lesion, differs from renal angiomyolipoma in terms of non-association with tuberous sclerosis, circumscription and male predominance. Another characteristic feature is the absence of epithelioid cells. Differential diagnosis includes lipoma, angiolipoma, angioleiomyoma, hemangioma, myolipoma and liposarcoma. It is distinguished from the above mentioned entities by the presence of a combination of thick-walled blood vessels, smooth muscle and fat.
Introduction: Gastrointestinal stromal tumour (GIST) is relatively rare. The clinical behaviour of GIST ranges
from benign to frank sarcoma. The diagnosis is established through histopathological examination and
immunohistochemistry profile. In Malaysia, the number of publications related to GIST is relatively rare. This
study was therefore conducted to examine the demographic, histopathological and immunohistochemical
features of GIST cases diagnosed in the Department of Pathology, Hospital Tengku Ampuan Afzan, Kuantan,
Pahang from 2009 until 2014. Methods: Past histopathological records were reviewed. Demographic and
histopathological and immunohistochemical data of patients diagnosed were collected. Results: There were
28 cases (14 males and 14 females) diagnosed as GIST. Mean age was 56.4 years, and the majority were
above 40 years of age (85.7%). Stomach was the most common location (42.9%), followed by small intestine
(28.6%). In 23 cases (82%), the tumours exhibited spindle cell morphology, while epithelioid cell and mixed
cell types were seen in 3 cases (11%) and 2 cases (7%), respectively. Five cases were categorised as very low
risk to low risk behaviour, while 18 cases were intermediate to high. None of the histological parameters
analysed which include tumour morphology, necrosis, haemorrhage, nuclear atypia and mean number of
mitoses showed significance difference between the different risk behaviour groups. Positivity with KIT
(CD117), considered to be the defining immunohistochemistry feature, was negative in 2 cases. Conclusion:
Although this study is a retrospective study, the findings contribute to the knowledge on GISTS in Malaysia.
Future research related to GISTs in Malaysia should focus on molecular analyses for KIT and PDGFRA
mutations for diagnostic confirmation especially in KIT-negative cases and also for the purpose of
therapeutic response correlations.
We report a rare case of an asymptomatic latent melioidosis lesion in a posttraumatic splenectomy specimen from a diabetic patient. The 2-cm yellowish, lobulated lesion was found in the splenic parenchyma well away from the traumatized areas. Microscopically, it consisted of a central area of necrosis and exudate surrounded by macrophages, epithelioid cells, lymphocytes, and occasional multinucleated giant cells. Burkholderia bacilli were detected by a novel in situ hybridization (ISH) assay, and confirmed by polymerase chain reaction and sequencing to be Burkholderia pseudomallei. As melioidosis was not suspected initially, bacterial culture was not done but electron microscopy showed morphologically viable and dividing bacilli in the lesion. Moreover, the surgical wound became infected with B. pseudomallei several days post-surgery. After treatment with ceftazidime and trimethoprim/sulfamethoxazole, the wound infection cleared. We believe this could be a unique case of asymptomatic latent melioidosis in the spleen. In endemic countries, chronic granulomas should be investigated for B. pseudomallei infection, and if available, ISH may be helpful for diagnosis.