Acquired C1-esterase inhibitor deficiency: Three case reports and commentary on the syndrome

Acquired C1-esterase inhibitor deficiency is a rare syndrome which usually presents with episodes of angioedema. Most patients have an underlying lymphoproliferative disorder. It is important to gastroenterologists, haematologists, immunologists and dermatologists, as these are the more likely specialties to which the patient will present. Recognition of the syndrome is important not only for diagnostic purposes but for investigating and treating any associated underlying lymphoproliferative disorders. In some instances the angioedema may precede the lymphoma by many years. Optimal patient management requires that both angioedema and the underlying lymphoma be recognized and treated.     

Radiation-induced soft-tissue and bone sarcoma.

From the records of Memorial Hospital of the past 50 years, 47 cases with an established diagnosis of radiation-induced sarcoma were identified and divided into two groups: the first included 20 cases of soft-tissue sarcoma arising from irradiated tissues, and the second comprised 27 cases of bone sarcoma arising from normal bones in the irradiated field. Medians for the latent periods from irradiation to diagnosis of bone and soft-tissue sarcoma were 11 and 12, years, respectively. In bone sarcomas, the latent period was longer after larger radiation doses and children appeared to be more susceptible to cancer induction than adults. Criteria for establishing the diagnosis of radiation-induced sarcoma and the magnitude of the risk of bone sarcoma are discussed.     

The effect of different calcium antagonists and a calcium agonist on the metabolism of propranolol by isolated rat hepatocytes

Summary— The influence of the dihydropyridine calcium entry blockers nicardipine, amlodipine, nifedipine, isradipine and of the dihydropyridine calcium entry promotor BAY K 8644 on the disappearance rate of propranolol by isolated rat hepatocytes was compared to the effect of diltiazem and verapamil, two non-dihydropyridine calcium channel blockers and known inhibitors of hepatic cytochrome P450 mixed function oxidases. All compounds dose-dependently inhibited the disappearance rate of propranolol. Nicardipine and isradipine were more potent in inhibiting the disappearance rate of propranolol than the other dihydropyridines and than diltiazem and verapamil. The inhibitory effect of nicardipine on the disappearance rate of propranolol was not stereoselective and was not influenced by age.     

Case report 280

A fracture involving the trochlear ossification center as well as the medial epicondyle is a more serious injury than simple avulsion of the medial epicondyle. This diagnosis may be difficult in young children before the secondary centers are ossified. Radiographic clues to this injury in a young child are localized soft tissue swelling over the medial aspect of the elbow accompanied by a metaphyseal flake and/or a positive fat pad sign. In the older child, separation of the ossified medial epicondyle with a positive fat pad sign suggests a more complex injury.     

The pathology of malignant fibrous histiocytoma of bone. A study of 130 patients

Since 1927, 130 patients with well-documented malignant fibrous histiocytoma of bone have been diagnosed and treated at Memorial Hospital for Cancer and Allied Diseases. This sarcoma is 10 times less frequent than osteogenic sarcoma in this hospital. It most commonly occurred spontaneously (72%), whereas in the rest (28%) it followed previous radiation or various pre-existent osseous conditions, most often Paget's disease. The appendicular skeleton was the commonest site of involvement. The majority of the patients were middle-aged or older adults with a mean of 40.5 years of age; only 21.5% were 21 years or younger. Histologically, the lesions were subclassified as fibrous (62%), histiocytic or xanthomatous (30%), and malignant giant cell tumor (8%) variants. Older patients were more likely to have a secondary malignant fibrous histiocytoma, especially following radiation or Paget's disease. Overall survival estimates at 2 years and 5 years were 71% and 53%, respectively. Survival was not dependent on the histologic subtype of the lesion, but was strongly influenced by the histologic grade of malignancy. Important prognostic factors were the age of the patients and whether the lesions were primary de novo or secondary sarcomas: the older patients and those with secondary lesions did substantially worse.     

The value of thallium and three-phase bone scans in the evaluation of bone and soft tissue sarcomas

Thirty-seven patients with newly diagnosed or treated sarcomas had 47 sets of sequential thallium scans (TS) followed by three-phase bone scan (TPBS) on the same day. The diagnosis in all patients was verified by biopsy (n=40) or long-term follow-up studies (n=7). The sensitivity, specificity, and accuracy of TS and TPBS in detecting sarcomatous lesions was calculated: TS sensitivity was 88%, specificity 69%, and accuracy 83%; blood flow (BF) and blood pool (BP) sensitivity was 91%, specificity 54%, and accuracy 81 %; delayed bone scan (DB) sensitivity was 88%, specificity 38%, and accuracy 74%. In 17 studies the flow and blood pool parts of the TPBS and TS demonstrated the soft tissue component of sarcomas, which would have been missed if only the delayed bone scan had been performed. The TS lesion to normal tissue ratio alone was not very helpful in differentiating sarcomas from benign conditions because some benign lesions are highly cellular and vascular while some malignant lesions, such as chondrosarcoma, have poor vascularity and a less cellular chondroid matrix. However, when the thallium ratio was correlated with similar ratios calculated from yhe BP image, it was found that if the TS lesion to normal tissue ratio exceeded the BP lesion to normal tissue ratio (12 patients), the specificity for detecting sarcomatous lesions was 100%. Nevertheless, the reverse was not true. The positive predictive value of this observation was 100% and the negative predictive value was 37%.