Absence of thyroid transcription factor-1 expression is associated with poor survival in patients with advanced pulmonary adenocarcinoma treated with pemetrexed-based chemotherapy.

INTRODUCTION: Adenocarcinoma is the commonest histologic subtype of lung cancer and is often identified by immunohistochemical staining for thyroid transcription factor-1 (TTF-1). However, up to 20% of lung adenocarcinomas do not express TTF-1, and there is uncertainty regarding the significance of this. We aimed to evaluate the prognostic effect of TTF-1 expression status on survival in patients treated with pemetrexed-based chemotherapy for advanced adenocarcinoma of the lung. METHODS: This retrospective study included patients treated with pemetrexed-based chemotherapy for stage IIIB/IV lung adenocarcinoma, who had known TTF-1 expression status. Clinical and demographic data were obtained from medical records. Overall survival (OS) was estimated using the Kaplan-Meier method, and differences in survival between groups assessed using the Cox proportional hazards model. RESULTS: Forty-four patients were identified with documented TTF-1 expression: 35 with TTF-1-positive and 9 with TTF-1-negative disease. Patients in the TTF-1-negative group had poorer performance scores than those in the TTF-1-positive group (ECOG 2: 67 vs 20%, p = 0.008), and received less chemotherapy (median cycles 2 vs 4, p = 0.009), and were fewer in treatment with doublet regimens (22 vs 69%, p = 0.013). OS was significantly shorter in the TTF-1-negative group than in the TTF-1-positive group (2.4 vs 11.5 months, HR 8.38, p < 0.0001). CONCLUSIONS: In this group of patients treated with pemetrexed-based chemotherapy for advanced pulmonary adenocarcinoma, absence of TTF-1 expression was associated with an aggressive tumor phenotype, poorer performance status, and poor survival. This subgroup of patients should be recognized as having a distinct clinical course, with limited benefit from standard chemotherapy.

Metastatic pleomorphic adenoma to the supraspinatus muscle: a case report and review of a rare aggressive clinical entity.

We report a case of a 65-year-old female with a recurrent right parotid pleomorphic adenoma (PA) 24 years after initial surgical excision. Positron-emission tomography (PET) and computed tomography (CT) demonstrated an unusual suspicious FDG-avid erosive rim enhancing mass centered in the right supraspinatus muscle. Cytology from CT-guided aspiration of the mass was consistent with a histologically benign PA, and the patient was diagnosed with metastatic pleomorphic adenoma (MPA). The patient later developed diffuse pulmonary metastases and died within 3 months. MPA, although rare, is recognised as a potentially lethal malignant complication of recurrent or longstanding benign PA. As no biochemical or genetic parameters are predictive of malignant change, patients presenting with recurrent PA should be considered for screening for metastatic disease.

Recurrent Non-islet Cell Tumor Hypoglycemia Secondary to Recurrent Renal Sarcoma.

INTRODUCTION: Non-islet-cell tumor hypoglycemia (NICTH) is a rare paraneoplastic syndrome encountered in the setting of a wide variety of benign and malignant tumors. CASE PRESENTATION: A 46 year old lady was referred to our unit, with a large left sided retroperitoneal mass found on surveillance imaging on a background of renal sarcoma 6 years previously, for which she had a left nephrectomy. She had initially presented with symptoms of hypoglycaemia which was a result of tumor secretion of insulin like growth factor 2. She was counselled regarding the recurrence and listed for excision. On the day of surgery she developed symptomatic hypoglycaemia. The tumour was completely resected from the nephrectomy bed. The tumour was histologically identical to the initial tumor. CONCLUSION: We report a rare case of recurrent non-islet cell hypoglycaemia in a lady with recurrent malignancy. Her hypoglycaemic episodes fully resolved on each occasion following resection. There have been reports of NICTH associated with recurrent retroperitoneal tumours and synchronous thyroid tumours and uterine leiomyomata. NICTH should be considered in patients with a known malignancy who present with recurrent hypoglycaemia. This is, to the best of our knowledge at the time of writing, the first case in the literature of recurrent NICTH secondary to recurrent renal sarcoma.