Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem disorder characterised by the development of multiple hamartomas in numerous organs. It is caused by mutations of two tumour suppressor genes, TSC1 on chromosome 9q34 and TSC2 on chromosome 16p13.3, which encode for hamartin and tuberin respectively. The interaction between these two proteins, the tuberin-hamartin complex, has been shown to be critical to multiple intracellular signalling pathways, especially those controlling cell growth and proliferation. TSC may affect skin, central nervous system, kidneys, heart, eyes, blood vessels, lung, bone and gastrointestinal tract. Small series and case reports have documented that in tuberous sclerosis patients many endocrine system alterations might occur, affecting the function of the pituitary, parathyroid and other neuroendocrine tissue. There have been scattered reports of the involvement of such tissue in the pathological process of TSC, but no systematic review as to whether this is a true association. We have therefore systematically assessed all available published literature in this area. We conclude that there may be an association with pituitary and parathyroid tumours, and two recent descriptions of Cushing's disease are especially intriguing. However, the evidence seems more firm in the case of islet cell tumours, particularly insulinomas. As these latter may cause changes in mental state that may be confused with the cerebral manifestations of TSC per se, it is particularly important for physicians working with these patients to be aware of the putative and indeed likely association.

A review of the published literature reveals 51 reported cases of temozolomide treatment for pituitary tumours, including 20 prolactinomas. Fifteen of the 20 prolactinomas showed a good response to temozolomide. Our analysis demonstrates a strong association between MGMT-negative staining and a good response to temozolomide (OR 9.35, P = 0.0030). Current clinical practice is to use temozolomide as a salvage therapy after all conventional modalities of treatment have failed. We suggest that, in selected cases, consideration should be given to using temozolomide earlier in the treatment algorithm.

Objective: It is suggested that patients with acromegaly have an increased risk of colorectal cancer and pre-malignant adenomatous polyps. However, the optimum frequency with which colonoscopic screening should be offered remains unclear. Design: To determine the optimum frequency for repeated colonoscopic surveillance of acromegalic patients. Methods: We retrospectively reviewed the case records of all patients with acromegaly seen in our centre since 1992: 254 patients had at least one surveillance colonoscopy, 156 patients had a second surveillance colonoscopy, 60 patients had a third surveillance colonoscopy and 15 patients had a fourth surveillance colonoscopy. Results: The presence of hyperplastic or adenomatous polyps was assessed in all patients, while one cancer was detected at the second surveillance. At the third surveillance, mean (GS.D.) serum IGF1 levels (ng/ml) in patients with hyperplastic polyps were significantly higher than those with normal colons (P!0.05). The presence of an adenoma rather than a normal colon at the first colonoscopy was associated with a significantly increased risk of adenoma at the second (odds ratio (OR) 4.4, 95% confidence interval (CI) 1.9-10.4) and at the third (OR 8.8, 95% CI 2.9-26.5) screens. Conversely, a normal colon at the first surveillance gave a high chance of normal findings at the second (78%) or third surveillance (78%), and a normal colon at the second colonoscopy was associated with normality at the third colonoscopy (81%). Conclusions: Repeated colonoscopic screening of patients with acromegaly demonstrated a high prevalence of new adenomatous and hyperplastic colonic polyps, dependent on both the occurrence of previous polyps and elevated IGF1 levels.

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Using Prolactin as a concurrent index of pituitary venous effluent helps us recognize whether pituitary venous blood has been accurately sampled. Normalizing the IPS/peripheral ratios with Prolactin helps to improve the accuracy of the result and reduces the false-negative rate. With regards to the usefulness/validity of this test in clinical practice, it is relevant, reproducible and is easily adaptable from the existing diagnostic sequence.