Biomedical subjects

Anne W M Lee

Publications and source records attributed to Anne W M Lee.

6 recordsLinked to original sources

PubMed2026

A systematic review of international/national guidelines for the management of nasopharyngeal carcinoma: Convergence and divergence of recommendations.

Increasing numbers of clinical practice guidelines have been published by international/national groups for nasopharyngeal carcinoma (NPC), providing valuable references for clinicians in making evidence-based decisions on treatment. However, there are substantial discrepancies in various recommendations, leading to uncertainties in choosing the optimal strategies. The authors systematically searched databases and organizational websites for NPC guidelines published between January 2000 and November 2025. All identified guidelines underwent quality appraisal; in total, 26 clinical practice guidelines rated recommended for use were included. The recommendations covering all management aspects (diagnosis, staging, radiotherapy, systemic therapy, follow-up surveillance, biomarkers, and salvage of recurrent/metastatic diseases) were summarized and comparatively analyzed for consistency and disparities. Strong consensus exists for diagnostic workup, staging systems, and induction chemotherapy plus concurrent chemoradiotherapy for advanced disease, whereas marked disparities exist on radiotherapy details, particularly target volume delineation, elective coverage extent, and dose specifications. Although systemic therapy strategies for different stage groups were mostly consistent, substantial disparities exist in alternative options and treatment details. This first comprehensive systematic synthesis of international NPC guidelines provides a practical reference for clinicians to understand all recommendations and select optimal options based on local resources and expertise while identifying current controversies that demand future research for further standardization and harmonization.

Humans↗

PubMed2004

Primary tumor volume of nasopharyngeal carcinoma: prognostic significance for local control.

PURPOSE: To study the prognostic significance of primary tumor volume on local control of nasopharyngeal carcinoma. METHODS AND MATERIALS: Between 1998 and 2001, 308 consecutive patients with nasopharyngeal carcinoma treated with radical intent were staged with MRI. On the basis of the extent of tumor infiltration outlined by a diagnostic radiologist, the gross tumor volume of the primary and involved retropharyngeal nodes (GTV-P) was delineated by a radiation oncologist for three-dimensional conformal radiotherapy to the nasopharyngeal region using the Helax-TMS Planning System. All patients were treated with 2 Gy daily to a total dose of 70 Gy in 6-7 weeks. Additionally, chemotherapy was given to 128 patients (42%). RESULTS: The median GTV-P for the whole series was 22 cm(3) (range, 1.4-218 cm(3)). Although the GTV-P varied substantially within each T stage, the overall correlation between these two parameters was strongly significant (p <0.01), with the median GTV-P 2.7 cm(3) for T1, 13.2 cm(3) for T2, 28.1 cm(3) for T3, and 65.5 cm(3) for T4. With a median follow-up of 1.9 years (range, 0.1-3.9 years), the 3-year local failure-free rate was 87%. The 3-year local failure-free rate was 97% for patients with a GTV-P <15 cm(3) compared with 82% for those with a GTV-P > or =15 cm(3) (p <0.01). On multivariate analysis (with T stage as a covariate), GTV-P remained an independent prognostic factor for the local failure-free rate (hazard ratio, 1.01; 95% confidence interval, 1.00-1.02; p <0.01). CONCLUSION: Our data suggested that GTV-P is a strongly significant factor for predicting local control of nasopharyngeal carcinoma. The risk of local failure was estimated to increase by 1% for every 1 cm(3) increase in primary tumor volume.

Adolescent↗

PubMed2004

Magnetic Resonance for T-staging of nasopharyngeal carcinoma--the most informative pair of sequences.

OBJECTIVE: To evaluate the most informative pair of sequences in magnetic resonance (MR) for T-staging of nasopharyngeal carcinoma (NPC). METHODS: The MR images of 134 patients with newly diagnosed NPC, from 1996 to 2002, were retrospectively reviewed. All the patients were scanned using 1.5 Tesla MR systems. The images of the nasopharynx were reviewed by two qualified radiologists to determine the positive findings and the T-stage by UICC (6th edition) System, using each sequence separately. The T-stage derived from a single MR sequence was then compared with the T-stage based on the five selected sequences to assess the number and percentage of patients who were being understaged. Therefore, the overall percentage accuracy of each single sequence could be determined. A pair of sequences providing information to achieve almost 100% diagnostic accuracy was then derived. RESULTS: The overall percentage accuracy of five individual sequences of the nasopharynx is as follows: contrast-enhanced (CE) fat suppression (FS) axial T1 (94.8%), CE FS coronal T1 (88.1%), FS axial T2 (85.8%), non-contrast enhanced (NE) axial T1 (78.4%) and non-contrast enhanced (NE) coronal T1 (77.6%). CE FS axial T1 has the best accuracy. All the structures that are missed in CE FS axial T1, which lead to apparent understaging, are appreciated in NE axial T1-weighted images. CONCLUSION: Individual sequences supplement each other in the NPC staging. CE FS axial T1 is the most informative individual sequence. Combination of CE FS axial T1 and NE axial T1 of the nasopharynx provides sufficient information to achieve almost 100% diagnostic accuracy in T-staging; therefore, both should be included in the MR-staging protocol.

Humans↗

PubMed2003

Changing epidemiology of nasopharyngeal carcinoma in Hong Kong over a 20-year period (1980-99): an encouraging reduction in both incidence and mortality.

Epidemiological data from the Hong Kong Cancer Registry for the period 1980-99 were analyzed. Altogether 21,768 new cases of nasopharyngeal carcinoma (NPC) and 8,664 related deaths were registered. In both genders, the peak incidence occurred in the 50-59 years age group, and this age distribution pattern remained similar throughout. The age-standardized incidence rate steadily decreased from 28.5 in 1980-84 to 20.2 in 1995-99 per 100,000 males, and from 11.2-7.8 per 100,000 females, resulting in a total decrease of 29% for males and 30% for females over this 20-year period. The magnitude of total decrease in NPC mortality amounted to 43% and 50%, respectively, as the age-standardized mortality rate steadily decreased from 13.7 in 1980-84 to 7.8 in 1995-99 per 100,000 males, and from 4.5-2.2 per 100,000 females. The age-standardized mortality/incidence ratio also decreased from the peak of 0.48 in 1980-84 to 0.39 in 1995-99 for males, and from 0.40-0.29 for females. Females had significantly lower age-standardized incidence (male/female ratio 2.5-2.6, p < 0.01) and mortality (male/female ratio 3.0-3.5, p< 0.01) throughout the whole period. Furthermore, females had consistently lower mortality/incidence ratio: 0.29 vs. 0.39 in 1995-99. These data are highly suggestive of significant improvement in prevention and control of NPC in Hong Kong. Closer scrutiny of the differences in intrinsic and extrinsic factors between the genders might help to show important factors affecting oncogenesis and prognosis. Possible ways for further reduction of incidence and mortality are discussed.

Adult↗

PubMed2003

Contribution of radiotherapy to function preservation and cancer outcome in primary treatment of nasopharyngeal carcinoma.

Development of primary treatment for nasopharyngeal carcinoma is summarized and the contribution of radiotherapy (RT) is reviewed. Accumulation of knowledge, together with technological advances, has led to significant improvement both for tumor control and organ preservation. With contemporary RT, it is possible to achieve a 10-year disease-specific survival of 47% with a severe late complication rate of 5%. Presenting stage is one of the most important prognostic factors, but unfortunately late presentation and delayed diagnosis remains a common problem. The average local control rate is 80% for tumor confined within the nasopharynx, but only 50% for those associated with erosion of the base of the skull or cranial nerve involvement. Nodal deposits from nasopharyngeal carcinoma are much more radiosensitive than those from other head and neck cancers. An average control rate of 75% can be achieved with RT alone, even in patients with nodes > 6 cm in diameter. Successful locoregional control is important, not only because it is crucial for survival but also because it is associated with a lower incidence of distant failure (29% versus 41%). Distant failure remains a sinister problem, especially for patients presenting with advanced T or N-stage cancers. Randomized trials exploring the value of additional chemotherapy are reviewed. The significant improvement in 3-year overall survival achieved by the addition of concurrent and adjuvant chemotherapy (78% versus 47%) recently reported is encouraging, but remaining uncertainties are also discussed.

Brachytherapy↗

PubMed2002

Factors affecting risk of symptomatic temporal lobe necrosis: significance of fractional dose and treatment time.

PURPOSE: To study the factors affecting the risk of symptomatic temporal lobe necrosis after different fractionation schedules. METHODS AND MATERIALS: One thousand thirty-two patients with T1-2 nasopharyngeal carcinoma treated with radical radiotherapy in Hong Kong during 1990-1995 were studied. They were treated at four different centers with similar techniques but different fractionation schedules: 984 patients were given 1 fraction daily throughout (q.d.), and 48 patients were irradiated twice daily (b.i.d.) for part of the course. The median total dose was 62.5 Gy (range 50.4-71.2), dose per fraction was 2.5 Gy (range 1.6-4.2), and overall treatment time (OTT) was 44 days (range 29-70). In addition, 500 patients received supplementary doses for parapharyngeal extension, 113 received booster doses by brachytherapy, and 114 received sequential chemotherapy using cisplatin-based regimes. RESULTS: Altogether, 24 patients developed symptomatic temporal lobe necrosis: 18 from the q.d. group and 6 from the b.i.d. group. The 5-year actuarial incidence ranged from 0% (after 66 Gy in 33 fractions within 44 days) to 14% (after 71.2 Gy in 40 fractions within 35 days). Multivariate analyses showed that the risk was significantly affected by the fractional effect of the product of total dose and dose per fraction (hazard ratio [HR] = 1.04, 95% confidence interval [CI] 1.02-1.05), OTT (HR 0.88, 95% CI 0.80-0.97), and b.i.d. scheduling (HR 13, 95% CI 3-54). Repeating the analyses for patients treated with the q.d. schedules confirmed the independent significance of OTT in addition to the product of total dose and dose per fraction. CONCLUSION: The tentative results suggest that in addition to fractional dose, the OTT also had significant impact on the risk of temporal lobe necrosis, and b.i.d. scheduling increased the hazard further.

Adolescent↗