Delayed diagnosis of tuberculosis: risk factors and effect on mortality among older adults in Hong Kong.

OBJECTIVE: To assess the risk factors and effects of delayed diagnosis on tuberculosis (TB) mortality in Hong Kong. METHODS: All consecutive patients with TB notified in 2010 were tracked through their clinical records for treatment outcome until 2012. All TB cases notified or confirmed after death were identified for a mortality survey on the timing and causes of death. RESULTS: Of 5092 TB cases notified, 1061 (20.9%) died within 2 years of notification; 211 (4.1%) patients died before notification, 683 (13.4%) died within the first year, and 167 (3.3%) died within the second year after notification. Among the 211 cases with TB notified after death, only 30 were certified to have died from TB. However, 52 (24.6%) died from unspecified pneumonia/sepsis possibly related to pulmonary TB. If these cases are counted, the total TB-related deaths increases from 191 to 243. In 82 (33.7%) of these, TB was notified after death. Over 60% of cases in which TB diagnosed after death involved patients aged ≥80 years and a similar proportion had an advance care directive against resuscitation or investigation. Independent factors for TB notified after death included female sex, living in an old age home, drug abuse, malignancy other than lung cancer, sputum TB smear negative, sputum TB culture positive, and chest X-ray not done. CONCLUSIONS: High mortality was observed among patients with TB aged ≥80 years. Increased vigilance is warranted to avoid delayed diagnosis and reduce the transmission risk, especially among elderly patients with co-morbidities living in old age homes.

Optimising the utility of pleural fluid adenosine deaminase for the diagnosis of adult tuberculous pleural effusion in Hong Kong.

INTRODUCTION: Pleural fluid adenosine deaminase level can be applied to rapidly detect tuberculous pleural effusion. We aimed to establish a local diagnostic cut-off value for pleural fluid adenosine deaminase to identify patients with tuberculous pleural effusion, and optimise its utility. METHODS: We retrospectively reviewed the medical records of consecutive adults with pleural fluid adenosine deaminase level measured by the Diazyme commercial kit (Diazyme Laboratories, San Diego [CA], United States) during 1 January to 31 December 2011 in a cluster of public hospitals in Hong Kong. We considered its level alongside early (within 2 weeks) findings in pleural fluid and pleural biopsy, with and without applying Light's criteria in multiple scenarios. For each scenario, we used the receiver operating characteristic curve to identify a diagnostic cut-off value for pleural fluid adenosine deaminase, and estimated its positive and negative predictive values. RESULTS: A total of 860 medical records were reviewed. Pleural effusion was caused by congestive heart failure, chronic renal failure, or hypoalbuminaemia caused by liver or kidney diseases in 246 (28.6%) patients, malignancy in 198 (23.0%), non-tuberculous infection in 168 (19.5%), tuberculous pleural effusion in 157 (18.3%), and miscellaneous causes in 91 (10.6%). All those with tuberculous pleural effusion had a pleural fluid adenosine deaminase level of ≤100 U/L. When analysis was restricted to 689 patients with pleural fluid adenosine deaminase level of ≤100 U/L and early negative findings for malignancy and non-tuberculous infection in pleural fluid, the positive predictive value was significantly increased and the negative predictive value non-significantly reduced. Using this approach, neither additionally restricting analysis to exudates by Light's criteria nor adding closed pleural biopsy would further enhance predictive values. As such, the diagnostic cut-off value for pleural fluid adenosine deaminase is 26.5 U/L, with a sensitivity of 87.3%, specificity of 93.2%, positive predictive value of 79.2%, negative predictive value of 96.1%, and accuracy of 91.9%. Sex, age, and co-morbidity did not significantly affect prediction of tuberculous pleural effusion using the cut-off value. CONCLUSION: We have established a diagnostic cut-off level for pleural fluid adenosine deaminase in the diagnosis of tuberculous pleural effusion by restricting analysis to a level of ≤100 U/L, and considering early pleural fluid findings for malignancy and non-tuberculous infection, but not Light's criteria.

Newer fluoroquinolones for treating respiratory infection: do they mask tuberculosis?

Possible masking of tuberculosis (TB) in treatment of community-acquired respiratory infection by newer fluoroquinolones has not been examined in randomised controlled trials. We undertook a randomised, open-label controlled trial involving adults with community-acquired pneumonia or infective exacerbation of bronchiectasis encountered in government chest clinics in Hong Kong. 427 participants were assigned by random permutated blocks of 20 to receive either amoxicillin clavulanate (n = 212) or moxifloxacin (n = 215). Participants were followed for 1 yr for active pulmonary TB. Excluding three participants with positive baseline culture, 13 developed active pulmonary TB: 10 (4.8%) out of 210 were given amoxicillin clavulanate, and three (1.4%) out of 214 were given moxifloxacin. The difference was significant by both proportion and time-to-event analysis. Post hoc analysis showed a significant decrease in the proportion with active pulmonary TB from 4.8% to 2.4% and 0% among participants given amoxicillin clavulanate (n = 210), moxifloxacin for predominantly 5 days (n = 127) and 10 days (n = 87), respectively. The log rank test for trend also showed a significant difference between the three subgroups. Regression models reaffirmed the linear effect; the adjusted odds ratio (95% confidence interval) of active pulmonary TB after moxifloxacin exposure up to predominantly 10 days was 0.3 (0.1-0.9). Newer fluoroquinolones appear to mask active pulmonary TB.

Peak plasma rifampicin level in tuberculosis patients with slow culture conversion.

The clinical utility of therapeutic drug monitoring in tuberculosis has not been adequately evaluated by controlled clinical trials. To examine the relationship between slow culture conversion and peak plasma rifampicin level (Cmax-rfm) in a case-control study, patients with persistence of positive sputum smear despite at least 8 weeks of directly observed treatment with standard pyrazinamide-containing regimens were enrolled prospectively in government chest clinics from 16 December 2005 to 15 November 2006. Patients with multidrug-resistant tuberculosis, human immunodeficiency virus infection, or poor treatment adherence were excluded. Cases referred to patients with persistence of positive culture whereas controls had negative culture despite positive smear. Blood was checked at 2 and 4 hours post-dosing to capture Cmax-rfm. A cohort of 88 patients was identified. After excluding 16 patients, there were 36 controls and 36 cases. None had symptoms of malabsorption. Cmax-rfm was below 6 mg/l among 47% of controls and 44% of cases. Univariate and multiple logistic regression analyses showed no significant association between slow culture conversion and Cmax-rfm after logarithmic transformation. Thus, there is probably no association between Cmax-rfm and slow culture conversion.

Fluorogenic nanocrystals for highly sensitive detection of C-reactive protein.

A solid-phase sandwich fluorescence immunoassay using nanocrystals of a fluorogenic precursor, fluorescein diacetate (FDA), conjugated with monoclonal antibodies for the detection of C-reactive protein (CRP), is described. FDA nanocrystals were coated with distearoylglycerophosphoethanolamine (DSPE), modified with amino(poly(ethylene glycol))(PEG(2000)-Amine) as an interface for coupling biomolecules. CRP was chosen as a model analyte because of its widely accepted role as a marker for acute inflammation and prospective heart failure. A low limit of detection (1.10 microg l(-1)) and high precision (CV = 2.72-9.48%) were achieved. Following the immunoreaction, the monoclonal anti-CRP conjugated nanocrystals were released by hydrolysis and dissolution instigated by the addition of a large volume of organic solvent-sodium hydroxide mixture. Using human serum samples from 66 patients with high heart attack risk and 19 healthy blood donors, this CRP fluorescence immunoassay showed a good correlation to the commercially available, turbidimetric immunoassay for CRP. This result was corroborated by the Bland-Altman plot that showed a mean difference between the two methods of only 0.36+/-1.46 mg l(-1). The study demonstrates that the organic fluorogenic FDA nanocrystals can be applied for the detection of CRP, which is a clinically interesting plasma protein with a low limit of detection.

Effect of Flos carthami on stress-activated protein kinase activity in the isolated reperfused rat heart.

The apoptotic death of cardiomyocytes due to ischemia/reperfusion is one of the major complications of heart disease. Ischemia/reperfusion has been shown to lead to the activation of the stress-activated protein (SAP) kinases and the p38/reactivating kinase (p38/RK). In this study, the direct effect of an aqueous Flos carthami (FC) extract on SAP kinases was investigated. When isolated rat hearts were perfused by Langendorff mode with media containing FC extract prior to the induction of global ischemia and the subsequent reperfusion, SAP kinase activity was inhibited 95%. Untreated ischemic/reperfused hearts showed a 57% elevation in the activity of SAP kinase. The in vitro effect of these FC extracts on SAP kinase was also tested. At a concentration of 10 microg/ml, the aqueous FC extract resulted in 50% inhibition of SAP kinase activity in ischemic heart tissue. Our results showed that FC affected both the interaction of SAP kinase with c-jun as well as the phosphotransferase reaction. These results clearly demonstrate that extracts from Flos carthami exerted inhibitory effects on SAP kinase. The administration of the FC extract may lead to a modulation of the apoptotic effect of SAP kinase activation induced during ischemia/reperfusion.

Olfactory function in patients with nasopharyngeal carcinoma following radiotherapy.

The aim of this study was to examine the impact of radiation treatment on olfactory function in patients with nasopharyngeal carcinoma (NPC). An olfactory function test battery was administered to 25 adult NPC patients having received radiotherapy, 24 adult nasopharyngeal carcinoma patients awaiting to receive radiation treatment, and 36 adult normal control subjects. Members of the three groups were matched in terms of age, educational level, and full-scaled IQ score. Comparing the test results revealed that the NPC patients with radiotherapy had olfactory information processing impairments including absolute threshold, odour-tactile cross-modality matching, verbal identification of odours, and recall and recognition of identity of odours. The deficits of suprathreshold olfactory functioning in these patients did not seem to arise from impaired absolute threshold sensitivity. Provided that the results are reproducible, an evaluation of olfactory functioning in NPC patients during the period of radiotherapy may be useful for detecting or even avoiding side effects of radiation.

Aorta wall motion monitoring by 1-d MRI of perpendicular diameters.

A method for monitoring the cross-sectional size of blood vessels rapidly is introduced. The method creates a one-dimensional (1-D) profile of a strip along the diameter of a vessel using magnetic resonance imaging (MRI). The strips can be much wider than pixels in a typical two-dimensional (2-D) image to increase the signal-to-noise ratio. A second strip perpendicular to the first is also imaged sequentially to allow the detection, estimation, and correction of errors in diameter measurements resulting from the strip inadvertently covering a chord, rather than a diameter. Diameter measurements derived from 1-D profiles agree with measurements derived from 2-D images. This method is nearly an order of magnitude faster than 2-D MRI and has the potential for real-time implementation. J. Magn. Reson. Imaging 1999;10:833-840.

Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control.

OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the control of early stage nasopharyngeal carcinoma (NPC) treated with a combination of external radiotherapy and brachytherapy, MATERIALS & METHODS: We reviewed the records of 133 patients with early stage nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who received definitive radiotherapy in Chang Gung Memorial Hospital from 1979 to 1991. The median follow-up time was 7.1 years with a minimum of 2 years. All patients were treated with megavoltage external radiotherapy to the nasopharynx area (63-72 Gy) followed by high dose rate intracavitary brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4 Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used to examine the effect of several variables on prognosis. RESULTS: The 5-year rates were 86.4% for local control, 84.7% for disease free survival, 88.5% for actuarial survival and 84.2% for overall survival. The treatment group (combination of time and dose of irradiation) was the most important prognostic factor according to Cox's proportional hazard model. Patients receiving radiation at a total dose of < or = 75 Gy completed in < 12 weeks showed the best prognosis. CONCLUSION: Treatment time and total treatment dose are both important factors in treating early stage NPC. Decreasing the total radiation time to < 12 weeks and not exceeding a radiation dose of 75 Gy gave the best results.

The clinical implications of hydronephrosis and the level of ureteral obstruction in stage IIIB cervical cancer.

PURPOSE: There are two criteria for the diagnosis of Stage IIIB cervical cancer in the FIGO staging system: tumor fixation to the pelvic side wall and/or the presence of hydronephrosis due to tumor. However, we often encounter hydronephrosis without tumor fixed to the pelvic side wall or the level of ureteral obstruction not corresponding to the main tumor mass in the pelvis. The clinical implication of these phenomena remains unclear. We investigated the Stage IIIB population treated at the Mallinckrodt Institute of Radiology and hypothesized that, if hydronephrosis presents without tumor fixation to the pelvic side wall or if the level of ureteral obstruction is above the main pelvic tumor mass, it most likely resulted from external compression of ureter(s) by enlarged lymph nodes and, consequently, a worse outcome is expected. METHODS AND MATERIALS: From 1959 to 1989, there were 297 patients with Stage IIIB cervical cancer who received definitive radiation therapy at the Mallinckrodt Institute of Radiology and were assessable for the presence of hydronephrosis and the level of ureteral obstruction. There were 281 patients who presented with tumor fixed to the pelvic side wall, and 62 of them were associated with concurrent hydronephrosis. An additional 16 patients presented with hydronephrosis without tumor fixation to the pelvic side wall. Among these 78 documented cases of hydronephrosis, the level of ureteral obstruction was above the true pelvis in 39 patients, and below the true pelvis in the other 39. Radiation therapy was individualized according to tumor extension and configuration; para-aortic lymph nodes were not routinely treated except in patients with clinical evidence of nodal metastasis. RESULTS: The progression-free survival (PFS) at 5 years was 35% in 62 patients with hydronephrosis and tumor fixed to the pelvic side wall vs. 43% in 213 patients with tumor fixed to the pelvic side wall only (p=0.12). However, PFS at 5 years decreased to 23% in 16 patients who presented with hydronephrosis without tumor fixation to the pelvic side wall (p < 0.001). When the level of ureteral obstruction was investigated, 5-year PFS was 39% vs. 22%, respectively, for the obstruction below vs. above the true pelvis (p=0.02). The majority of patients with ureteral obstruction above the true pelvis died of distant metastasis. CONCLUSIONS: The additional presence of hydronephrosis did not significantly worsen the PFS among Stage IIIB patients with tumor fixation to the pelvic side wall. However, hydronephrosis without tumor extending to the pelvic side wall or the level of ureteral obstruction above the true pelvis was associated with poor outcome due to a significant increase in distant failure. We propose that this population be separated from current Stage IIIB classification.

Neuropsychological function in patients with nasopharyngeal carcinoma after radiotherapy.

A neuropsychological test battery was administered to 27 adult patients with nasopharyngeal carcinoma (NPC) who had received radiotherapy, 28 adult patients with NPC awaiting radiotherapy, and 35 normal adult controls. The 27 patients with radiotherapy had a conventional dosage, 220 cGy per fraction, or less. The median interval between the completion of radiotherapy and the evaluation of neuropsychological function was 1.7 years. Groups were matched for age and educational level. The results showed that our NPC group with radiotherapy had neuropsychological impairments in the areas of auditory attention/concentration, immediate and delayed verbal recall and immediate visual recall, and recent memory, higher-order visuospatial abilities, and bimanual dexterity. Thus neuropsychological dysfunction may occur in patients with NPC within the first 2 years after radiotherapy.

Concurrent 5-fluorouracil, leucovorin, etoposide, cisplatin and radiotherapy for locally advanced non-small cell lung cancer.

BACKGROUND: The prognosis of Stage III unresectable non-small cell lung cancer may be improved by concurrent chemoradiotherapy. In this study, we attempted to evaluate the feasibility, tolerance, efficacy and toxicities of the combination of thoracic radiation and chemotherapy with a novel regimen that included 5-fluorouracil, leucovorin, etoposide and cisplatin (the FLEP regimen) in the treatment of this group of patients. PATIENTS AND METHODS: From July 1995 to September 1996, 20 untreated patients with locally advanced non-small cell lung cancer were enrolled in the study. Radiation at a dose of 44 Gy was initially delivered in daily fractions of 2 Gy 5 days a week to the tumor and mediastinum, followed by a boost to the tumor (20 to 26 Gy according to patients tolerance). Concurrently with thoracic irradiation, patients were treated with chemotherapy consisting of cisplatin at the dose of 60 mg/m2/d for 1 day, etoposide at the dose of 60 mg/m2/d for 2 days, and 5-FU 500 mg/m2/d plus leucovorin 50 mg/d infusion for 48 hours. Cycles of chemotherapy were repeated every 3 weeks for a maximum of 3 cycles. RESULTS: Seventeen of 20 patients were assessable. The overall response rate was 70.6% (95% confidence interval = 49-92%). No complete response was achieved. The median response duration for all responding patients is not yet estimable, with a range of 3.5 to 15.5+ months. Eleven patients remain progression-free for 4 to 15 months. The median survival for the entire group is not estimable. The major toxicity was esophagitis. Other grade 3 or 4 toxicities were not frequently observed. CONCLUSION: Combined-modality therapy with FLEP regimen and radiation is a promising treatment with a high response rate and acceptable toxicity for locally advanced non-small cell lung cancer.

Sustained complete remission after incomplete chemoradiation complicated with pelvic cellulitis in a patient with recurrent cervical carcinoma.

We report on a 52-year-old female patient with a bulky, recurrent cervical carcinoma involving the vagina and bladder, who developed entero-recto-vesicovaginal fistulas and sepsis with pelvic cellulitis after external radiation of 40 Gy and 2 courses of concurrent chemotherapy. Chemoradiation was interrupted and an ileostomy was performed. After recovery, no residual tumor was detectable. Thirteen months after ceasation of chemoradiation, repair of vesicovaginal and rectovaginal fistulas via posterior sagittal approach was performed. Revision of double bowel ileostomy and ileo-T-colostomy was performed 17 months later. The patient enjoyed the restoration of enteral and urinary function only temporarily. She developed rectovesical fistula and underwent an ileostomy again 6 months later. She had another episode of peritonitis and upper gastrointestinal bleeding and expired at 4 years from initiation of salvage therapy. She had no evidence of cancer recurrence during a series of laparotomies and biopsies. The dramatic regression of the tumor may be attributed to its extraordinary radiosensitivity or chemosensitivity. The acute pelvic inflammatory complications may also contribute to the tumor cell killing. The prognosis of recurrent cervical carcinoma is invariably poor except in small tumors confined to vagina. This case gives support to the efficacy of chemoradiation and the potential role of biologic therapy in treatment of this dismal disease.

Acute toxicities and feasibility of altered fractionated radiotherapy in nasopharyngeal carcinoma.

BACKGROUND: Altered fractionated radiotherapy (AFR) has been used for many years in the treatment of cancer. Although AFR therapy improves tumor control, it also increases acute radiation toxicities, which may make patients withdraw from treatment. Here, we report on the efficacy of AFR in the treatment of nasopharyngeal cancer (NPC). METHODS: From September 1993 to October 1994, 68 NPC patients received AFR in Chang Gung Memorial Hospital-Linkou. The efficacy of two types of AFR were studied: (a) Hyperfractionated radiotherapy (HFT) in which irradiation was given twice a day throughout the radiotherapy course with a total radiation dose of 81.6 Gy/68 fractions in 7 weeks; and (b) Concomitant boost radiotherapy (CBT) in which additional concommitant radiotherapy was administered only during the last 2 weeks of the radiotherapy course. The total radiation dose of CBT was 72.3 Gy/42 fractions in 6 weeks. Twenty-six patients received HFT and 42 received CBT. RESULTS: The percentage of grade 3 complications was 73% in CBT and 65% in HFT. The mean number of treatment days was 57.1 in HFT (median, 53; range 48-63) and 43.9 in CBT (median, 43; range 40-60). No patient withdrew from or prolonged the treatment because of acute radiation toxicities. CONCLUSION: Our results demonstrated that NPC patients can tolerate HFT and CBT radiotherapy with sufficient psychological support. Further randomized trials will be continued in our institution.

Adaptive rival penalized competitive learning and combined linear predictor model for financial forecast and investment.

We propose a prediction model called Rival Penalized Competitive Learning (RPCL) and Combined Linear Predictor method (CLP), which involves a set of local linear predictors such that a prediction is made by the combination of some activated predictors through a gating network (Xu et al., 1994). Furthermore, we present its improved variant named Adaptive RPCL-CLP that includes an adaptive learning mechanism as well as a data pre-and-post processing scheme. We compare them with some existing models by demonstrating their performance on two real-world financial time series--a China stock price and an exchange-rate series of US Dollar (USD) versus Deutschmark (DEM). Experiments have shown that Adaptive RPCL-CLP not only outperforms the other approaches with the smallest prediction error and training costs, but also brings in considerable high profits in the trading simulation of foreign exchange market.

A longitudinal study of multimodal evoked potentials in patients following radiotherapy for nasopharyngeal carcinoma.

Radiation rhombencephalopathy and radiation myelopathy may occur in patients months or years after radiotherapy for malignancy of the head and neck. We obtained multimodal evoked potentials longitudinally in 26 patients with proven nasopharyngeal carcinoma. Recordings were made before radiotherapy and at 1 week, 3 months, 9 months, 15 months, and 24 months after radiotherapy. All absolute latencies of evoked response before and after radiation were within normal limits. However, the I-III interpeak latencies of brainstem auditory evoked potentials and the onset latencies of motor evoked potentials in the whole group of patients at 15 months after radiation were significantly longer than those before radiotherapy, whereas the latencies at 24 months were not significantly different. The N20 latencies of somatosensory evoked potentials after radiotherapy were significantly prolonged at 3 months of follow-up; the prolongation then became normal. They indicate that a subclinical reversible radiation-induced dysfunction may occur in the auditory, sensory, and motor systems.

Combination chemotherapy with carmustine and cisplatin before, during, and after radiotherapy for adult malignant gliomas.

Twenty-two patients, aged 16 to 67, who had malignant gliomas after surgical resection were treated with carmustine and cisplatin intravenous infusion before, during, and after radiotherapy. All patients had subtotal or total resection, or biopsy as the initial procedure. Twenty-one patients who had at least 2 cycles of chemotherapy and finished the whole course of radiotherapy were considered to be evaluable for responses. Among them, 5 had glioblastoma multiforme, 16 had anaplastic astrocytoma. The median time to tumor progression was 35 weeks (range 12-130 weeks) and median survival time was 66 weeks (range 10-156 weeks). Early progression occurred more frequently in patients with biopsy only and subtotal resection, and in patients with glioblastoma than in those with anaplastic astrocytoma. This combined modality treatment program was associated with reversible hematologic toxicity which was severe in 2 patients, and with ototoxicity in 1 patient, nephrotoxicity in 2 patients. Combination of carmustine and cisplatin with cranial irradiation for malignant gliomas is moderately toxic and appears to offer no obvious survival advantage compared with radiation therapy plus BCNU alone.

Localised plasmacytomas in Taiwan: comparison between extramedullary plasmacytoma and solitary plasmacytoma of bone.

The clinical features and response to therapy of 32 Chinese patients with localised plasmacytoma are presented, and a comparison between extramedullary plasmacytoma (EMP) and solitary plasmacytoma of bone (SPB) is made. Twenty-two patients had SPB and ten had EMP, accounting for 9% of all of our plasma cell neoplasms. Both groups had a male predominance with a median age of 54 years for SPB and 63 years for EMP. The common sites of SPB included vertebral bodies (15) and the skull (4). Most EMPs occurred in the oronasopharynx (6) and paranasal sinuses (2). An M-protein was detected in eight patients with SPB and in six with EMP. Seventeen patients with SPB and seven with EMP received radiation therapy, and all achieved initial local control. The pattern of failure in 22 patients with SPB manifested as local recurrence in two, multiple bone metastases without bone marrow plasmacytosis in two, multiple EMP progression in two, and development of multiple myeloma (MM) in one. There were two local recurrences, one further solitary bone involvement and one MM conversion in the EMP group. Local recurrence or dissemination was associated with the appearance of M-protein or an increase in the M-protein level in both groups. There was no significant difference in M-protein status or incidence and patterns of failure between the two groups. Patients with EMP had a more favourable overall survival than those with SPB (P = 0.03). The 5 year disease-free survival rate was 79% for EMP and 58% for SPB (P = 0.53). Patients aged less than 60 years had a better overall survival in the SPB group, but location of tumour, presence of M-protein, radiation dose and chemotherapy did not influence prognosis in either group. Our results indicate that adequate local therapy can result in long-term survival with a low frequency of MM progression for patients with localised plasmacytomas, and both EMP and SPB appear to be similar in terms of frequency and patterns of failure.

Solitary plasmacytoma of bone.

From 1978 to 1992, 19 patients were diagnosed with solitary plasmacytoma of bone (SPB) accounting for 5.5% of plasma cell neoplasms in Chang Gung Memorial Hospital. Fourteen were male and five were female, with ages ranging from 21 to 71 years (median, 53 years). M-protein was detected at diagnosis in five patients, and during follow-up in three. The most common sites of SPB were the vertebral bodies, with seven involving the thoracic, four involving the lumbar and two involving the cervical spine. The remaining sites included the skull in four, and femur and pelvis in one each. Fifteen of the patients received local radiotherapy, local control was achieved in all; nine patients were alive with no evidence of disease for seven to 77 months, two patients remained in apparent remission at 14 and 92 months, two patients progressed to multiple myeloma at 12 and 84 months, one patient developed extramedullary plasmacytoma at three months, and one patient died of intercurrent disease at four months. The four patients who were not treated with radiation therapy ultimately developed local recurrence or dissemination within four years. In our series, local recurrence or dissemination was always associated with the appearance of, or an increase in, the M-component; thus, measurement of M-protein is helpful in assessing tumor control or progression. Based on our experience and a review of the literature, it is recommended that irradiation of the primary sites is the treatment of choice. Chemotherapy is indicated in those patients with disease progression, recurrence, or dissemination.