miR-200 deficiency promotes lung cancer metastasis by activating Notch signaling in cancer-associated fibroblasts.

Lung adenocarcinoma, the most prevalent lung cancer subtype, is characterized by its high propensity to metastasize. Despite the importance of metastasis in lung cancer mortality, its underlying cellular and molecular mechanisms remain largely elusive. Here, we identified miR-200 miRNAs as potent suppressors for lung adenocarcinoma metastasis. miR-200 expression is specifically repressed in mouse metastatic lung adenocarcinomas, and miR-200 decrease strongly correlates with poor patient survival. Consistently, deletion of mir-200c/141 in the KrasLSL-G12D/+ ; Trp53flox/flox lung adenocarcinoma mouse model significantly promoted metastasis, generating a desmoplastic tumor stroma highly reminiscent of metastatic human lung cancer. miR-200 deficiency in lung cancer cells promotes the proliferation and activation of adjacent cancer-associated fibroblasts (CAFs), which in turn elevates the metastatic potential of cancer cells. miR-200 regulates the functional interaction between cancer cells and CAFs, at least in part, by targeting Notch ligand Jagged1 and Jagged2 in cancer cells and inducing Notch activation in adjacent CAFs. Hence, the interaction between cancer cells and CAFs constitutes an essential mechanism to promote metastatic potential.

Coblator-Assisted Endoscopic Transnasal Resection of a Large Nasopharyngeal Pleomorphic Adenoma.

BACKGROUND: Pleomorphic adenomas occurring in the adult nasopharynx are rare, with our literature search identifying only 11 previous English-language reports. We document the unusual case of a large nasopharyngeal pleomorphic adenoma that was resected using radiofrequency coblation via an endoscopic transnasal approach. METHODS: A 39-year-old male presented with worsening nasal congestion, intermittent otalgia, and a progressive change in voice. Flexible nasendoscopy showed a large homogeneous mass occupying the postnasal space, and computed tomography confirmed a 28 × 31 × 22 mm nasopharyngeal tumour. The biopsy-proven benign tumour was locally dissected using a coblator-assisted transnasal approach. RESULTS: Histology confirmed complete excision of a myoepithelial-rich pleomorphic adenoma. The patient was symptom-free postoperatively, and no signs of recurrence were seen at one-year follow-up. CONCLUSIONS: This is a useful addition to the existing literature on surgical procedures used to treat benign pathology in the nasopharynx. The minimally invasive technique was well tolerated and had favourable patient outcomes.

Nonsecretory multiple myeloma presenting as an intestinal tumor.

We report a case of a 43-year-old Caucasian man who presented with colicky abdominal pain and microcytic hypochromic anemia. The patient underwent a colonoscopy where a tumor was seen in the ascending colon; histology showed plasmacytoma of the colon. From the protein electrophoresis, no monoclonal band or free light chains were detected nor was urinary Bence Jones protein present. A bone marrow biopsy showed plasma cell myeloma. To the best of our knowledge, this is the first case of nonsecretory multiple myeloma presenting as plasmacytoma of the colon.

A case report of cecal plasmablastic lymphoma in a HIV-negative patient.

Plasmablastic lymphoma (PBL) is a unique type of diffuse proliferation of large neoplastic lymphoid cells most of which resemble B immunoblasts, but all tumor cells show the immunophenotype of plasma cells. It has a strong predilection for jaw and oral cavity in HIV-positive patients. Incidences of extraoral location of this tumor is increasingly being recognized especially in HIV-negative patients for example, stomach, jejunum, omentum, anorectum, lungs, testes, soft tissues, lymph nodes, bone marrow, skin, and central nervous system. We present a case of PBL found in cecum in an HIV-negative patient. It was accompanied by lung and lymph node involvement and presented as abdominal mass. This is only the second reported case of PBL originating in cecum.

Solid variant of alveolar rhabdomyosarcoma in the head and neck region: a case report of a diagnostic dilemma in a head and neck fine needle aspiration clinic.

BACKGROUND: Alveolar rhabdomyosarcoma (ARMS) is one of the major categories of rhabdomyosarcomas; it encompasses malignant tumors of striated muscle and occurs more frequently in the extremities. It is uncommonly reported in young adults and extremely rarely found in middle-aged and elderly patients. CASE: A 54-year-old man presented to a rapid head and neck clinic with a history of rapid enlargement of neck lumps on the right side of his neck over a period of 5 weeks. The diagnosis of an undifferentiated malignant small round cell tumor was made from cytologic examination of the aspirated sample, and biopsy of the lesion was advised. On histologic analysis, diagnosis of solid variant of ARMS was made. CONCLUSION: A solid variant of ARMS in an older population has not been published in the literature within the settings of a rapid head and neck clinic. Therefore, the remote possibility of this diagnosis should be considered in the differential diagnosis of a malignant, round cell tumor in fine needle aspiration cytology in an older patient's neck lump.

Endometrioid adenocarcinoma presenting in a patient 18 years after hysterectomy: a potential hazard of unopposed oestrogen therapy.

We present a case of endometrioid adenocarcinoma arising from extragonadal endometriosis 18 years after total abdominal hysterectomy with bilateral salpingo-oophorectomy. After the primary surgery the patient received 11 years of unopposed oestrogen hormone replacement therapy. She presented with symptoms of urinary retention and pelvic mass. Following resection, histopathology identified the mass as an endometrioid adenocarcinoma. The association between persistent endometriosis and the development of endometrial cancer are discussed here together with the risks of unopposed oestrogen in the development of such lesions.

Massive haemorrhagic adrenal metastases leading to sudden death: a case report.

Although adrenal glands are a common site of metastatic cancer, clinically significant haemorrhage into these is very uncommon with only a few cases having been previously published in the English literature. Here, a case of massive adrenal haemorrhage secondary to metastasis of lung cancer that led to the death of the patient is reported. To the best of our knowledge, such an acute death, without any prior medical attention or intervention, as a consequence of haemorrhagic adrenal metastasis has not been described before and is an important consideration in a person with lung cancer who dies unexpectedly.

Pathology of Toxoplasma myocarditis in acquired immunodeficiency syndrome.

Involvement of the myocardium by Toxoplasma gondii is seen in patients of acquired immunodeficiency syndrome (AIDS), mostly in association with toxoplasma encephalitis. Only few patients die as a direct result of cardiac dysfunction. Clinico-pathological findings of three cases of toxoplasma myocarditis are reported, one of which presented and died due to massive pericardial effusion. All cases showed diffuse myocarditis with parasites on histopathological examination. Incidence of toxoplasma myocarditis in patients dying with AIDS was 8.3% (3 out of 36 cases).

Clear cell adenocarcinoma of the maxillary sinus: a case report.

A variety of salivary gland tumours histologically show the presence of clear cells. Clear cell adenocarcinoma of salivary glands (CCASG) is a distinct clinico-pathologic entity arising in the minor salivary glands of mainly the oral cavity in elderly women and having a low grade malignant potential. A case occurring in the maxillary sinus and extending to the nasal cavity is reported.

Dedifferentiated chordoma--a case report.

A case of a recurrent sacro-coccygeal chordoma is reported which histologically showed an admixture of a conventional chordoma and a pleomorphic sarcoma. These tumours are called dedifferentiated chordomas and carry an ominous prognosis.

Primary squamous cell carcinoma of the ovary in a young patient. A case report.

A case report of a squamous cell carcinoma arising in a dermoid cyst of the ovary in a 29 year old patient is presented. Such an occurrence in young patients is unusual.