Congenital thiopurine methyltransferase deficiency and 6-mercaptopurine toxicity during treatment for acute lymphoblastic leukaemia

Two children with acute lymphoblastic leukaemia (ALL) taking daily 6-mercaptopurine as part of a national UK therapeutic trial repeatedly developed profound myelosuppression on 25% of the standard protocol dose. Both were found to have undetectable intracellular activity of thiopurine methyltransferase (TPMT), an enzyme controlling one of the major alternative catabolic pathways of 6-mercaptopurine, and both produced higher concentrations of cytotoxic drug metabolites at 10-25% of the protocol dose than other patients taking 100%. It is supposed that these patients represent the 0.33% of the normal population constitutionally lacking TPMT. It is important to recognise such individuals both to avoid fatal bone marrow failure through inadvertent overdosage, and to be reassured that an adequate drug effect can be achieved at around 10% of the standard dose.     

Multiple myeloma: evaluation by CT

Although patients who have multiple myeloma usually have straightforward clinical symptoms and corroborative radiographs, in some instances, these patients will present atypically, with symptoms suggesting active disease but radiographs that are normal or nonspecific. We reviewed the records of 32 patients who had documented multiple myeloma and had undergone CT examinations, assessing the value of those examinations. Although CT is not indicated in all patients who have multiple myeloma, it is especially useful in patients who have bone pain and normal or nonspecific radiographs. CT provided confirmatory information in all cases in which lesions were seen on radiographs. CT also frequently demonstrated a greater extent of disease than could be appreciated on the radiographs.     

Early effects of inhaled Ca-DTPA on the rat lung

Inhalation of calcium trisodium diethylenetriaminepentaacetate (Ca-DTPA) increases the removal of plutonium and other transuranics from the body. Data are required to determine possible biological effects from inhaled DTPA. p]Female rats were given a single or 12 daily, 2–4-h, inhalation exposures to aerosols of 10, 20 and 40% Ca-DTPA and the lungs were examined at 21 and 42 days following the last exposure. No pulmonary pathology was found from the single inhalation treatment with Ca-DTPA while only a slight, peripheral, histiocytosis was observed in the lungs of multiple-treated rats. There was no significant effect of DTPA treatments on body weight, lung weight, hematology or serum chemistry values.     

Tarsal navicular stress fractures: radiographic evaluation

Tarsal navicular stress fractures are a potential source of disabling foot pain in physically active individuals. The diagnosis of tarsal navicular stress fracture requires a high index of clinical and radiographic suspicion because the fracture is only rarely evident on routine radiographs or standard tomograms. The radiographic diagnosis of a tarsal navicular stress fracture may require anatomic anteroposterior tomograms or a radionuclide bone scan with plantar views. Radiographic examinations of 23 fractures in 21 patients are evaluated.     

A prospective study of concurrent cyclophosphamide/methotrexate/5-fluorouracil and reduced-dose radiotherapy in patients with early-stage breast carcinoma

BACKGROUND: Concurrent administration of chemotherapy and radiotherapy has the potential advantage of delaying neither treatment and providing radiation sensitization. However, the optimal approach to concurrent treatment in women with early-stage breast carcinoma remains undefined. We present updated results of a prospective protocol of concurrent cyclophosphamide/methotrexate/5-fluorouracil (CMF) and reduced-dose radiotherapy, focusing on tumor control and patient tolerance. METHODS: One hundred twelve women with AJCC Stage I or Stage II breast carcinoma with 0-3 positive axillary lymph nodes were enrolled in a prospective single-arm study of concurrent CMF and reduced-dose radiotherapy (39.6 gray [Gy] to the whole breast, 16-Gy boost). A high proportion of women had risk factors associated with an increased risk of local disease recurrence, including age <40 (32%), close or positive margins (37%), or lymphatic/vascular invasion (51%). The median follow-up period was 94 months. RESULTS: The 5-year overall survival rate was 94%. By 60 months, 5 patients (4%) experienced local disease recurrence and 19 patients (17%) experienced distant metastasis. There were no isolated regional lymph node recurrences. Local disease recurrence occurred in 1 of 25 patients (4%), 1 of 16 patients (6%), and 3 of 70 patients (4%) with positive, close (<1 mm), and negative margins, respectively. One patient developed acute myelogenous leukemia. An additional patient developed Grade 2 pneumonitis. Cosmetic results were not recorded uniformly for all patients and therefore could not be reliably analyzed. CONCLUSIONS: Concurrent CMF and reduced-dose radiotherapy resulted in a low level of late toxicity and excellent local tumor control, despite the large proportion of patients with substantial risk factors for local disease recurrence. Future studies of concurrent regimens, particularly in patients at high risk of local disease recurrence, are warranted.