Peter S. Y. Yu

Significant prognosticators after primary radiotherapy in 903 nondisseminated nasopharyngeal carcinoma evaluated by computer tomography

PURPOSE To evaluate the significant prognosticators in nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS From 1984 to 1989, 903 treatment-naive nondisseminated (MO) NPC were given primary radical radiotherapy to 60-62.5 Gy in 6 weeks. All patients had computed tomographic (CT) and endoscopic evaluation of the primary tumor. Potentially significant parameters (the patients age and sex, the anatomical structures infiltrated by the primary lesion, the cervical nodal characteristics, the tumor histological subtypes, and various treatment variables were analyzed by both monovariate and multivariate methods for each of the five clinical endpoints: actuarial survival, disease-free survival, free from distant metastasis, free from local failure, and free from regional failure. RESULTS The significant prognosticators predicting for an increased risk of distant metastases and poorer survival included male sex, skull base and cranial nerve(s) involvement, advanced Hos N level, and presence of fixed or partially fixed nodes or nodes contralateral to the side of the bulk of the nasopharyngeal primary. Advanced patient age led to significantly worse survival and poorer local tumor control. Local and regional failures were both increased by tumor infiltrating the skull base and/or the cranial nerves. In addition, regional failure was increased significantly by advancing Hos N level. Parapharyngeal tumor involvement was the strongest independent prognosticator that determined distant metastasis and survival rates in the absence of the overriding prognosticators of skull base infiltration, cranial nerve(s) palsy, and cervical nodal metastasis. CONCLUSIONS The significant prognosticators are delineated after the advent of CT and these should form the foundation of the modern stage classification for NPC.

A comparison of Ho's, international union against cancer, and American joint committee stage classifications for nasopharyngeal carcinoma

Five hundred sixty‐four nasopharyngeal carcinomas (NPC), mostly of undifferentiated histologic type, were studied for survival, distant metastasis, and local recurrence. All had computerized tomography of the nasopharynx and skull base (CT‐NP) and fiberoptic nasopharyngoscopy for evaluation of the primary tumor. Regional disease was assessed by palpation. A computer data base was formed on presentation, containing all information required for staging according to Hos, the International Union Against Cancer (UICC), and the American Joint Committee (AJC) classifications. The three were compared for their efficacy in predicting prognosis. Hos classification was superior to the other two because its overall stages differed from one another more significantly in the actuarial survival (ASR), disease‐free survival (DFS), and freedom from distant metastasis (FDM) rates, and its N staging was more accurate in predicting FDM. Stages T1 and T2 of UICC/AJC were similar in the freedom from local recurrence rate (FLR) and should be grouped together, equivalent to Hos T1. A more even patients number distribution among the stages also favored the use of Hos classification.

A Retrospective Study of the Role of Intracavitary Brachytherapy and Prognotic Factors Determining Local Tumour Control After Primary Radical Radiotherapy in 903 Non-Disseminated Nasopharyngeal Carcinoma Patients

The aims of this retrospective study were to determine the role of intracavitary brachytherapy given shortly after external beam radiotherapy in the primary radical treatment of non-metastatic nasopharyngeal (NPC) cancer patients, and the prognostic factors governing local tumour control. From 1984 to 1989, 903 patients with non-disseminated NPC who had had no previous treatment were managed at the Prince of Wales Hospital, where investigation and treatment methods had been standardized according to a departmental protocol. The external radiotherapy dose of 60.0-62.5 Gy in 6 weeks was given to all patients. Parapharyngeal booster radiotherapy with a single photon beam to 20 Gy in 2 weeks was given to those with parapharyngeal tumour extension. Computed tomography of the nasopharynx and skull base, and pretreatment nasopharyngoscopy and biopsy were performed in all patients. Nasopharyngoscopy was repeated at 4 weeks after the last day of external irradiation. Local persistence in 99 patients was treated additionally by intracavitary brachytherapy to 24 Gy in three fractions over 15 days. Fifty-one patients with early stage primary disease (Ho Stage T1 and T2n (nasal)) who responded completely to external radiotherapy were given adjuvant intracavitary brachytherapy to 18 Gy in three fractions over 15 days. Intracavitary therapy was an inadequate salvage treatment for the locally persisting T3, T20 (oropharyngeal) and T2p (parapharyngeal) disease, but there was a trend towards improved local control after intracavitary brachytherapy for the locally persisting T1 tumours. Adjuvant brachytherapy did not enhance local tumour control for the early T-stage tumours that completely responded to external radiotherapy. Both forms of intracavitary brachytherapy were safe with few and acceptable complications. In the 903 non-disseminated NPCs, the patients age and tumour involvement of the skull base and cranial nerves were significant independent prognostic factors governing local tumour control. In the 358 patients with Ho T3 disease, tumour involvement of the orbits and the laryngopharynx significantly worsened local tumour control. The presence of local persistence at 4 weeks after external radiotherapy, for which therapeutic brachytherapy was given, was marginally significant as a prognostic factor in addition to the presence of cranial nerve palsy.

Early tumour response and treatment toxicity after hyperfractionated radiotherapy in nasopharyngeal carcinoma

The aim of the present study was to undertake a planned interim analysis of a prospective randomized trial comparing the tumour response and the acute and subacute complications of hyperfractionated radiotherapy and conventional radiotherapy in non-metastatic nasopharyngeal carcinoma (NPC). 100 patients with newly diagnosed non-metastatic NPC were randomized to receive either conventional radiotherapy (Arm I) or hyperfractionated radiotherapy (Arm II). Stratification was done according to the T-Stage (modified Hos T-Stage classification). The biological effective dose (10 Gy) to the primary and the upper cervical lymphatics were 75.0 and 73.1 for Arm I and 84.4 and 77.2 for Arm II, respectively. Hyperfractionated radiotherapy was associated with significant mucositis which is of higher grade than conventional radiotherapy (p = 0.0001), but the duration of mucositis was similar between the two Arms and all study patients completed radiotherapy on schedule without interruption of radiotherapy. Early survival and tumour recurrence rates were comparable between the Arms. The preliminary results indicate that the hyperfractionated radiotherapy has excellent patient compliance in Chinese patients, with acceptable acute and subacute toxicities and the local and regional complete tumour response rates being comparable with conventional radiotherapy. The significance of the time required after start of radiotherapy to achieve a complete tumour response is discussed.

A retrospective comparison between different stage classifications for nasopharyngeal carcinoma

From 1984 to 1987, 659 patients with untreated nasopharyngeal carcinoma (NPC) were investigated by computed tomography of the nasopharynx and skull base, and fibreoptic nasopharyngoscopy. Thirty-one patients presenting with distant metastasis were treated palliatively; 628 were treated with intent to cure. Prospective staging was performed for the Hos classification but since all T- and N-stage data required for staging according to the Huangs, the Changsha and the UICC classifications were recorded and stored in a computer database, retrospective staging according to these classifications could be accurately performed. Hos classification was concluded to be the best in view of highly significant differences between the overall stages in survival and between N-stages in distant metastasis. The number of prognostically distinct overall stages and N-stages was greatest for Hos classification. Huangs T-stage classification was superior, however, because it emphasized the significant adverse effect on local tumour control of cranial nerve(s) palsy (Tn) and intracranial tumour extension (Tc). Changsha and UICC classifications were demonstrably less powerful in predicting NPC prognosis. Multiple sites of involvement within the nasopharynx by NPC had no adverse influence on local tumour control. The grouping together of both soft-tissue and skull-base lesions into Changshas T3 has been shown to be unjustified because of significant differences in local failure.

Image-guided localization of small lung nodules in video-assisted thoracic surgery

The advancement of imaging technology has recently facilitated single port minimally-invasive thoracic surgery techniques. Cone-beam computed tomography (CBCT) shows promising results in visualizing the target lesion and its surrounding critical anatomy, with an error of less than 2 mm. The integration of CBCT with the operating room (OR) to form the hybrid OR, provides unparalleled real-time imaging of the patient, which can be used with electromagnetic navigation bronchoscopy to confirm successful navigation and increase procedural accuracy particularly for small peripheral pulmonary targets. Furthermore, implantation of hookwires or microcoils that are widely used to localize the lesion can take place in the hybrid suite, eliminating the common complications and discomfort associated with the conventional workflow carried out in the radiology suite. Displacement leading to localization failure can be also reduced, and sublobar resection will be performed without resecting a larger area of parenchyma than desired. This one-stop, paradigm-shifting concept for simultaneously diagnosing and managing small pulmonary lesions in the hybrid OR can lead to reduced invasiveness and improved patient care.

Penetrating thoracic injury with retained foreign body: can video-assisted thoracic surgery take up the leading role in acute management?

Video-assisted thoracic surgery (VATS) is widely adopted in acute management of patient with thoracic trauma, but its use in penetrating thoracic injuries with retained foreign bodies were rarely reported. We described three of such cases using VATS as the first line approach. Identification of injuries, control of bleeders, clot evacuation, resection of damaged lung parenchyma and safe retrieval of foreign bodies were all performed via complete VATS within short operative time. Patient were uneventfully discharged during early post-operative period. We suggest that, for haemodynamically stable patients, VATS offers a safe and minimally-invasive alternative to conventional thoracotomy for penetrating thoracic injury with retained foreign bodies.

Mitral valve repair using a semirigid ring: patient selection and early outcomes

Background Commonly used complete mitral annuloplastic rings include saddle-shaped and semirigid rings, with no clear indication for either type. A semirigid ring may be preferred in patients whose native mitral saddle shape is well maintained. We present our experience of using semirigid rings for mitral valve repair. Methods We routinely measured the annular height-to-commissural width ratio by 3-dimensional transesophageal echocardiography prior to mitral repair. We generally chose a semirigid (Memo 3D) ring in patients whose annular height-to-commissural width ratio was normal (≥ 15%). The same semirigid ring with an additional chordal guiding system (Memo 3D ReChord) was selected for patients with anterior leaflet or bileaflet pathology. Over an 18-month period, 66 patients with severe degenerative (n = 60) or functional (n = 6) mitral regurgitation had Memo 3D (n = 32) or Memo 3D ReChord (n = 34) rings implanted. Results Postoperative 3-dimensional transesophageal echocardiography was completed in all patients (mean follow-up 7 ± 5 months). The majority of patients had no or mild residual mitral regurgitation; only two had moderate (2+) mitral regurgitation. There was no mortality at 30-days or on midterm follow-up. Conclusions Our series represents the first Asian clinical experience using the Memo 3D ReChord ring. Although the long-term durability of mitral repair with this type of semirigid annuloplastic ring warrants further validation, our current clinical data are encouraging.

Endovascular Fenestration for Distal Aortic Sealing After Frozen Elephant Trunk With Thoraflex

We describe a case of total arch replacement with frozen elephant trunk for chronic type B aortic dissecting aneurysm, which resulted in inadvertent landing of the frozen elephant trunk into the false lumen. A radiofrequency puncture system-assisted controlled endovascular fenestration of the dissection flap was performed at the upper abdominal aorta and subsequent thoracic endovascular stenting, successfully redirecting the blood flow from the false to the true lumen. Our case illustrated a possible way to seal distal reentry in chronic type B aortic dissection.

Coil Embolization of Diverticulum of Kommerell: A Targeted Hybrid Endovascular Technique

A 57-year-old man was incidentally found to have a dissected diverticulum of Kommerell originating from aberrant origin of right subclavian artery during follow-up for treated colon cancer. A right carotid-axillary bypass was followed by embolization of aberrant artery and the diverticulum by deployment of multiple detachable coils using the Penumbra Ruby System (Penumbra, Alameda, CA). Angiography after embolization showed exclusion of flow to the aberrant artery and a patent right carotid-axillary bypass. The patient recovered uneventfully and remained well for 12 weeks after the operation, without any complications. We believe this targeted endovascular approach can avoid complications related to the coverage of thoracic aorta and reduce the risk of access vessel trauma.