Langerhans Cell Histiocytosis with Good Response to Low-Dose Imatinib: Case Report and Literature Review.

Langerhans cell histiocytosis (LCH) is a rare neoplastic disease characterized by infiltration of histiocytes and dendritic cells into body organs. While treatment is better established in pediatrics, there is still no consensus on therapy in the adult population. Imatinib has shown promising results in some case reports and a small clinical trial. We present here a fifty-nine-year-old patient with LCH in the lung, liver, and bone who responded well to an imatinib dose of 100 mg daily. Her symptoms improved within 3 months of treatment, and subsequent positron emission tomography-computed tomography (PET/CT) showed resolution of 18F-fluorodeoxyglucose (FDG)-avid lesions.

Coinfection of HPVs Is Associated with Advanced Stage in Colorectal Cancer Patients from Qatar.

High-risk human papillomaviruses (HPVs) are considered risk factors in the origin of several human malignancies, such as breast, cervical, head and neck, as well as colorectal cancers. However, there are no data reported on the HPV status in colorectal cancer in the State of Qatar. Therefore, we herein examined the presence of high-risk HPVs (16, 18, 31, 33, 35, 45, 51, 52, and 59), using polymerase chain reaction (PCR) in a cohort of 100 Qatari colorectal cancer patients, and their association with tumor phenotype. We found that high-risk HPV types 16, 18, 31, 35, 45, 51, 52, and 59 were present in 4, 36, 14, 5, 14, 6, 41, and 17% of our samples, respectively. Overall, 69 (69%) of the 100 samples were HPV positive; among these, 34/100 (34%) were positive for single HPV subtypes, while 35/100 (35%) of the samples were positive for two or more HPV subtypes. No significant association was noted between the presence of HPV and tumor grade, stage, or location. However, the presence of coinfection of HPV subtypes strongly correlated with advanced stage (stage 3 and 4) colorectal cancer, indicating that the copresence of more than one HPV subtype can significantly worsen the prognosis of colorectal cancer. The results from this study imply that coinfection with high-risk HPV subtypes is associated with the development of colorectal cancer in the Qatari population.

Case Report: Tuberculosis-Induced Autoimmune Hemolytic Anemia.

Tuberculosis (TB) is an infectious disease that affects different organs, causing multiple complications, including hematological sequelae. One of the most common TB-hematological complications is anemia of chronic disease. Very rarely autoimmune hemolytic anemia (AIHA) has been reported as an uncommon manifestation of TB. In this case, we present a female who presented with refractory AIHA, which was attributed to disseminated TB. The patient responded well to steroids, anti-TB medications, and rituximab.

Well-Differentiated Liposarcoma of the Hypopharynx Exhibiting Myxoid Liposarcoma-like Morphology with MDM2 and DDIT3 Co-Amplification.

Well-differentiated liposarcoma (WDL) is one of the most common soft tissue sarcomas in adults. It has a predilection for middle-aged males and arises in deep-seated locations such as retroperitoneum, mediastinum, and spermatic cord. Its occurrence in young individuals at the hypopharyngeal region is an exceedingly rare event. Myxoid liposarcoma (ML)-like changes can seldom occur in some cases of WDL, which makes the diagnosis of WDL more challenging. Amplification of DDIT3 gene in a subset of cases of WDL has shown to be associated with such unique morphology. Herein, we present a case of a 36-year-old gentleman who presented with difficulty in breathing and swallowing for 3 months duration. CT scan of the neck revealed a lesion along the posterior wall of the hypopharynx measuring 3.5 cm. Histopathologic examination revealed a tumor composed of lobules of oval to spindle cells in a prominent myxoid stroma with delicate chicken-wire vasculature. In the vicinity, there were lobules composed of variably sized adipocytes separated by thick fibrous septa that contains atypical hyperchromatic spindle cells. By immunohistochemistry, the tumor cells in both components were immunoreactive for CDK4, but negative for MDM2. Fluorescence in-situ hybridization (FISH) confirmed the presence of MDM2 gene amplification. There was no evidence of FUS-DDIT3 gene rearrangement, however, DDIT3 gene was also amplified. The diagnosis of well-differentiated liposarcoma with prominent myxoid stroma was rendered. This is the first documentation of WDL with ML-like morphology harboring co-amplification of MDM2 and DDIT3 in the hypopharynx.