The diagnostic challenge of coexistent sarcoidosis and thyroid cancer – a retrospective study

Background Sarcoid lesions may mimic metastatic disease or recurrence in thyroid cancer (TC) patients as both diseases may affect the lungs and lymph nodes. We present the first study to systematically evaluate the clinical course of patients with (TC) after adjuvant radioactive iodine therapy (RIT) and concomitant sarcoidosis of the lung or the lymph nodes. Methods We screened 3285 patients and retrospectively identified 16 patients with TC (11 papillary thyroid cancer (PTC), 3 follicular thyroid cancer (FTC), 1 oncocytic PTC, 1 oncocytic FTC) and coexisting sarcoidosis of the lung and/or the lymph nodes treated at our institute. All patients had undergone thyroidectomy and initial adjuvant RIT. Challenges in diagnosing and the management of these patients were evaluated during long term follow-up (median 4.9 years (0.8–15.0 years)). Results Median age at first diagnosis of TC was 50.1 years (33.0–71.5 years) and of sarcoidosis 39.4 years (18.0–63.9 years). During follow-up, physicians were able to differentiate between SA and persistent or recurrent TC in 10 of 16 patients (63%). Diagnosis was complicated by initial negative thyroglobulin (Tg), positive Tg antibodies and non-specific imaging findings. Histopathology can reliably distinguish between SA and TC in patients with one suspicious lesion. Conclusion Physicians should be aware of the rare coexistence of sarcoidosis and TC. Lymphadenopathy and pulmonary lesions could be metastases, sarcoidosis or even a mix of both. Therefore, this rare patient group should receive a thorough work up including histopathological clarification and, if necessary, separately for each lesion.

A phase II trial of pemetrexed in patients with recurrent thymoma or thymic carcinoma

7079 Background: Few prospective trials have been conducted in patients with advance thymic malignancies. Pemetrexed a multi-targeted antifolate with a broad range of clinical activity, but previously untested in thymic malignancies. As a result, a phase II trial was initiated to evaluate the clinical activity of pemetrexed in previously treated patients with thymoma (THY) and thymic carcinoma (TC). Methods: From February, 2005 to November, 2005, twenty-seven previously treated patients with unresectable stage IVA (n = 16) or stage IVB (n =11) disease were treated with pemetrexed at a dosage of 500 mg/m2 every three weeks for a maximum of 6 cycles or until undue toxicity or progressive disease. All patients received folic acid, vitamin B12 and steroid prophylaxis. Profile of patients include: median age = 52 years (range 26–84); M: F = 13:14; PS 0/1= 17/10; median number of prior therapies = 2 (range 1–6); 21 had prior radiation therapy; and histology (THY = 16, TC = 11). Results: The median number of cycles administered was 5 (range 1–6). Eleven patients had grade 3 toxicities including: dyspnea, infections, fatigue, abnormal chemistries and neutropenia. No Grade 4 toxicities were noted. Accrual was completed in November, 2005 with four patients still on therapy. In 23 fully evaluable patients, two complete and two partial responses (RECIST) were noted. All four responding patients had had stage IVA thymoma. Five patients progressed on therapy and two patients discontinued therapy for intolerance to chemotherapy (constipation, dyspnea) and 1 patient for progressive Morvan’s Syndrome. The median time to progression for all patients was 45 weeks (THY = 45.4 weeks vs. TC = 5.1 weeks). With three deaths thus far, the median overall survival has not been reached. Conclusions: Pemetrexed is an active agent in a heavily pretreated population of patients with recurrent thymoma. Patients with recurrent thymic carcinoma appear to have a much more aggressive clinical course than thymoma. [Table: see text]

Extent of digestion affects the success of amplifying human DNA from blood meals of Anopheles gambiae (Diptera: Culicidae)

The success of distinguishing blood meal sources of Anopheles gambiae Giles through deoxyribonucleic acid (DNA) profiling was investigated by polymerase chain reaction (PCR) amplification at the TC-11 and VWA human short tandem repeats (STR) loci. Blood meal size and locus had no significant effect on the success of amplifying human DNA from blood meals digested for 0, 8, 16, 24 and 32 h (P = 0.85 and 0.26 respectively). However, logistic regression found a significant negative relationship between time since ingestion and the success probability of obtaining positive PCR products among meals digested for between 8 and 32 h (P = 0.001). Approximately 80% of fresh blood meals were successfully profiled. After 8 h, the proportion of blood meals that could be successfully profiled decreased slowly with time after ingestion, dropping to below 50% after approximately 15 h. There was no significant difference in the success of amplifying human DNA from blood meals of mosquitoes killed at time 0 and 8 h after ingestion (P = 0.272).