Neck dissection for non-squamous malignancy.

Of 1030 patients who underwent neck dissection (radical, modified or selective) in a 27-year period 103 had malignant neck nodes from a primary site in the head and neck with a histological diagnosis other than squamous carcinoma. There were 71 men and 32 women in this group with a mean age of 55 years. 28 patients had neck dissection as part of their initial treatment and 75 for later nodal recurrence. Five-year survival was 52% (40-63%). Survival was site dependent, best for thyroid tumours and worst for tumours of the major salivary glands (chi 1(2) = 6.52, P < 0.05). Histology significantly affected survival, best for papillary tumours and worst for melanoma and undifferentiated tumours (chi 1(2) = 3.85, P < 0.05). Survival was worse with advanced N stage but varied little with node level. The number of nodes invaded had a highly significant effect on survival (chi 4(2) = 23.94, P < 0.001), but extracapsular rupture had no effect. Advanced T stage at the time of surgery had a significant adverse effect on survival using univariate analysis, but this effect disappeared using multivariate analysis. In the 75 patients who had neck dissections for nodal recurrence the presence of a simultaneous recurrence at the primary site had no significant effect on survival. These patients had a better 5-year survival than patients having neck dissection for squamous disease, but the usual predictors of survival in squamous carcinoma do not always apply to non-squamous malignancy.     

Lymph node metastases in the lower neck

Current knowledge suggests that lymph node metastases in the lower neck (supraclavicular fossa and posterior triangle) are associated with a poor survival. Very little systematic work has been published on this subject. This was a retrospective study carried out on a database where all patients were entered in a prospective manner over a 35-year period using a standard pro-forma. Data on 168 patients presenting with a lower neck node metastasis were retrieved. The main outcome measures were: association between variables and tumour-specific survival. Data were displayed in contingency tables and analysed by chi-square and categorical modelling. Recurrence and survival were plotted in a cause-specific manner using the Kaplan Meir method. Differences in curves were analysed using the log rank test. Multivariate analysis was carried out using Cox's proportional hazard model. The only association was between site and node level and histology. Head and neck tumours were associated with squamous histology (P = 0.0004) and supraclavicular nodes (P = 0.0047). Survival time was not significantly different when lower-neck lymph node metastasis from the head and neck was compared to non-head and neck metastasis: 5-year survival 30% and 10% respectively (P = 0.1363). Survival with posterior triangle metastases was significantly better than supraclavicular metastases (P = 0. 0059), confirmed on multivariate analysis. Laterality of metastasis had no effect on survival (P < 0.0001). There was no significant difference in survival between squamous and non-squamous metastases on Cox regression (P = not significant). There were 85 head and neck primaries including lymphomas, 53 infraclavicular primaries and 30 unknown primaries. There were 73 squamous cell carcinomas, 27 adenocarcinomas, 34 lymphomas, 28 undifferentiated tumours and six other tumours. Nearly half the primary tumours were below the clavicle. Survival was unaffected by laterality, primary site or histology, but was better for posterior triangle nodes.     

Soft tissue cervical metastases of squamous carcinoma of the head and neck

Some 497 of 3085 patients with squamous cell carcinoma of the head and neck treated between 1963 and 1990 had a later radical neck dissection at some time after initial treatment. The histological slides were all reviewed, firstly to confirm the presence of squamous cell carcinoma within the neck, and secondly to ascertain whether the metastasis was to soft tissue, to a lymph node or to both. The presence of extracapsular rupture in lymph node deposits was also assessed. Of the 497 patients, 138 had soft tissue deposits only, and 359 had nodal deposits only. Of the patients with nodal deposits 165 had extracapsular rupture and 194 did not. The 5-year survival of the 138 patients with soft tissue metastases was 27% compared with 33% for patients with extracapsular rupture and 50% for patients with no extracapsular rupture. Weighted logistic regression showed that soft tissue deposits were significantly more common in patients in poor general condition, plus poorly differentiated squamous cell carcinoma plus T₄ tumours (P < 0.005), and in patients with poorly differentiated squamous cell carcinoma plus T₄ tumours (P < 0.025). Cox's multivariate analysis with backward elimination showed that gender, histological differentiation, site of primary tumour and age of patient had no statistically significant effect on survival. The number of nodes (P < 0.0001), the presence of extracapsular rupture (P < 0.0001) and the presence of soft tissue free metastases (P < 0.001) were all highly significant. The N-status at recurrence also reached statistical significance (P < 0.0001).     

Second radical neck dissection

We report a series of 96 patients (62 men and 34 women) undergoing a second radical neck dissection for enlarged contralateral cervical nodes after primary treatment of a squamous cell carcinoma of the head and neck, including an ipsilateral radical neck dissection. The proportion of patients requiring a second later neck dissection varied from 0% for tumours of the nasopharynx, nasal cavity and paranasal sinuses, to 5% for tumours of the hypopharynx. The incidence of second neck dissection was not determined by the original T stage of the primary tumour, but patients with enlarged nodes at presentation were 5 times more likely to need a second neck dissection than those with no palpable nodes at presentation. Also, patients with a poorly differentiated tumour were twice as likely to need a second neck dissection as those with a well differentiated tumour. The overall 5-year survival after second neck dissection was 35% and the perioperative mortality 1.92%. Significant factors predicting survival after a second neck dissection were the time to recurrence, the clinical neck node status at recurrence, the number of histologically invaded nodes in the neck and the presence of extra-nodal disease.     

Cutaneous malignant melanoma of the head and neck

A computer-aided analysis of 5,109 patients with malignant melanoma was performed. Patient population characteristics according to body site (head and neck, extremity, and trunk) were determined for the following parameters: sex, histologic type of melanoma, Clark's level, Breslow thickness, age, clinical status of regional nodes, presence or absence of ulceration, and recurrence. Head and neck melanomas accounted for 17% of the total population (N=877). A detailed analysis of general population characteristics according to subsites within the head and neck region (ear, face, neck, nose, and scalp) was performed. Survival characteristics were determined for head and neck patients according to lymph node surgery, histologic type of tumor, and tumor thickness. The effect on survival of lymph node dissection (elective for stage I disease and therapeutic for stage II disease) was analyzed by univariate and multivariate methods. Elective lymph node dissection (ELND) was performed on 77 patients and 39 patients underwent therapeutic nodal dissection (TLND). Overall, survival was significantly improved following ELND as compared to TLND; however, multivariate analysis indicated the improved survival was related to variations of age within the population rather than the beneficial effect of lymph node surgery. Elective lymph node dissection did significantly reduce the incidence of recurrence for head and neck patients (p=0.002). Since recurrence was demonstrated to be directly related to survival, the trend toward improved survival following ELND after 5 years was felt to be important. There was no difference in survival according to the histologic type of melanoma.     

The role of neck dissection after chemoradiotherapy for oropharyngeal cancer with advanced nodal disease

OBJECTIVE: To analyze and compare the effectiveness of sequential platinum-based chemotherapy and radiotherapy with and without selective neck dissection in patients with N2a and greater stage node-positive squamous cell carcinoma of the oropharynx. DESIGN: Nonrandomized controlled trial. SETTING: Tertiary referral center. PATIENTS: Sixty-six patients with squamous cell carcinoma of the oropharynx staged N2a or greater. INTERVENTIONS: Platinum-based induction chemotherapy followed by definitive radiation therapy; and selective neck dissections 6 to 10 weeks following the completion of radiation therapy in patients with radiographic evidence suggesting residual neck disease. MAIN OUTCOME MEASURES: Locoregional recurrence and disease-free survival. RESULTS: Of 66 patients, 24 (36%) had complete responses in the primary local tumor (oropharynx) and regional disease (neck nodes), as assessed clinically and radiographically. These patients had lower rates of locoregional recurrence than did patients showing no or partial responses, but the differences were not significant (P>.05). Of 18 patients undergoing neck dissection, 10 (56%) had pathological evidence of residual tumor. Patients showing a complete response of regional and neck disease had significantly improved disease-specific and overall survival (P = .01 for both) compared with patients showing no or partial responses of their neck disease. Patients with no or partial responses who underwent neck dissections had significantly improved overall survival compared with similar patients who did not undergo neck dissections (P = .002). CONCLUSIONS: Even in patients with bulky nodal disease, a complete response in the neck to sequential chemotherapy and radiotherapy may indicate that neck surgery is not necessary for good locoregional control and improved disease-free survival. Neck dissection is recommended for patients with no or partial radiographic responses.     

Interstitial irradiation for squamous carcinoma of the oral cavity

Interstitial radiation delivered by iridium 192 implants was used to treat 38 patients with squamous carcinoma of the oral cavity. Thirty-six patients had either T1 or T2 tumours and no patient had palpable nodes at the time of implantation. Control of the primary tumour was achieved in all but 2 patients; these 2 were successfully treated by surgery. Fifteen patients (39%) went on to develop metastatic neck nodes. Nine were cured by radical neck dissection but the remaining 6 died of their disease. This gives a 5-year actuarial survival of 81%. Since all deaths occurred after the development of metastatic disease in the neck with control of the primary lesion, the evidence for and against prophylactic treatment of the neck lymphatics in clinically negative necks was reviewed. Prophylactic irradiation of the neck is probably preferable to any form of neck dissection but clear evidence that this improves long-term survival compared with careful follow-up and radical neck dissection for palpable nodes is still lacking.     

影响早期舌癌预后的因素及颈部的治疗

目的 分析早期舌体鳞癌的预后相关因素及颈淋巴处理方式对生存率的影响,探讨早期舌癌的颈部治疗策略.方法 回顾性分析1994年1月至2003年12月期间152例经手术治疗的早期舌癌患者的临床及随访资料,任意分为颈部观察组与颈清扫组两大组,其中颈清扫组分为肩胛舌骨肌上清扫组和全颈清扫组(即全颈清扫和改良颈清扫).分析早期舌癌预后的临床病理因素和颈部治疗与否及不同的颈淋巴处理方式对颈部复发转移和生存率的影响.结果 全组病例随访5年以上或至患者死亡,5年随访率为94.7%.颈部观察组32例与颈清扫组120例的颈部复发率分别为34.4%和14.2%,差异有统计学意义(χ2=6.865,P<0.01);Kaplan-Meier法统计5年生存率分别为68%和79%,差异无统计意义(χ2=1.699,P>0.05).肩胛舌骨肌上清扫组与全颈清扫组的颈部转移复发率及5年生存率差异均无统计学意义(P值均>0.05).病理诊断有淋巴结转移和治疗后颈部复发转移患者的5年生存率明显低于无淋巴结转移和治疗后无颈部复发转移者,差异均有统计学意义(P值均<0.01).结论 隐匿性淋巴转移和复发是影响早期舌癌预后最主要的因素.肩胛舌骨肌上淋巴清扫虽然不能提高5年生存率,但能明显地降低颈部复发率.鉴于早期舌癌的隐匿性高且颈部复发挽救率低,建议对未过中线的早期舌癌应行同侧Ⅰ、Ⅱ、Ⅲ区的清扫,以减少颈部复发率.     

Survival following recurrent malignant melanoma of the head and neck

A retrospective analysis of 877 patients who had malignant melanoma of the head and neck identified 366 patients who developed recurrent disease. Sex, race, age, histology, Clark level, thickness, ulceration, lymph node status, lymph node dissection, site of recurrence, and time to recurrence were analyzed to determine their effect on survival following the development of recurrent disease. Survival following the development of recurrence was found to be influenced by the site of first recurrence and the age of the patient at the time of recurrence. For a given age, patients who had initial recurrences at distant sites were three times as likely to die following recurrence than patients with local recurrence. Patients who had initial recurrences at distant sites were twice as likely to die following recurrence than patients with regional sites of recurrence (p<0.001).     

Conversion from Selective to Comprehensive Neck Dissection: Is It Necessary for Occult Nodal Metastasis? 5-Year Observational Study

Objectives

To compare the therapeutic results between selective neck dissection (SND) and conversion modified radical neck dissection (MRND) for the occult nodal metastasis cases in head and neck squamous cell carcinoma.

Methods

Forty-four cases with occult nodal metastasis were enrolled in this observational cohort study. For twenty-nine cases, SNDs were done and for fifteen cases, as metastatic nodes were found in the operative field, conversion from selective to MRNDs type II were done. Baseline data on primary site, T and N stage, extent of SND, extracapsular spread of occult metastatic node and type of postoperative adjuvant therapy were obtained. We compared locoregional control rate, overall survival rate and disease specific survival rate between two groups.

Results

Among the 29 patients who underwent SND, only one patient had a nodal recurrence which occurred in the contralateral undissected neck. On the other hand, among the 15 patients who underwent conversion MRND, two patients had nodal recurrences which occurred in previously undissected neck. According to the Kaplan Meier survival curve, there was no statistically significant difference for locoregional control rate, overall survival rate and disease specific survival rate between two groups (P=0.2719, P=0.7596, and P=0.2405, respectively).

Conclusion

SND is enough to treat occult nodal metastasis in head and neck squamous cell carcinoma and it is not necessary to convert from SND to comprehensive neck dissection.     

Planned Early Neck Dissection Before Radiation for Persistent Neck Nodes After Induction Chemotherapy

Optimal management of advanced neck metastases as part of an organ preservation treatment approach for head and neck squamous carcinoma (HNSC) is unclear. Since 1989, our management paradigm for patients on organ preservation was modified to incorporate planned early neck dissection before radiation therapy for patients who did not achieve a complete response (CR) of neck nodes after induction chemotherapy (IC). The purpose of this study was to determine if planned early neck dissection is a safe and effective approach in the management of advanced nodal disease as part of organ preservation. Fifty-eight consecutive patients with advanced HNSC who were entered in organ preservation trials using induction chemotherapy and radiation with surgical salvage were studied. Median follow-up was 26 months. Of the 58 patients, 71% were stage IV. Patients were grouped by nodal response to chemotherapy and N class, and were analyzed with respect to patterns of recurrence, complications, and survival. Overall, the rate of CR of neck nodes was 49%. Fifty-one percent had less than a complete response of neck nodes after IC and required planned early neck dissection. There were no significant differences in patterns of recurrence, complications, interval time to start of radiation, recurrence, or survival rates between the CR and less than CR groups. These data suggest that planned early neck dissection for patients with less than CR in the neck after IC is not detrimental with respect to neck relapse or overall survival. We believe that planned early neck dissection can be safely incorporated into future organ preservation treatment protocols for patients with advanced head and neck carcinoma.     

Non-squamous malignancy in lymph nodes: the occult primary

The present study presents 105 patients seen at a head and neck specialist clinic with a neck gland which subsequently proved to be a non-squamous malignancy. Of the 105 patients, 50 patients were eventually found to have a tumour in the head and neck region, 30 to have a distant primary and in 25 no primary site was ever found. The majority of patients were diagnosed in the clinic after careful examination and most of the remainder were diagnosed during endoscopy/biopsy. Chest radiography was the most useful investigation for diagnosing primary tumours of the lung. The 5-year-survival for the whole group of 105 patients was 28% (95% CI 17–39). The 5-year-survival for the head and neck primary tumour group was 44% (95% CI 25–60). The median survival of patients with a distant primary tumour was only a 6 months, there was one 5-year-survivor. The median survival for those in whom the primary was never discovered was 18 months. However, a reasonable proportion of these patients survived, five being alive at 5 years. The difference between survival for the three groups was statistically significant (P < 0.001). The most common histological type was undifferentiated/anaplastic tumours (37 out of 105) and this was followed by adenocarcinoma (33 out of 105). There was a significant difference in the survival between these two groups (χ²= 2.02, d.f. = 1, P= NS). Multi-variate analysis suggested that survival was better in the older age group and was affected by histology (P= 0.0093, P= 0.0332 respectively). The present study suggests that the treatment of patients in whom the primary site is eventually found to be in the head and neck region is rewarding with the same survival as a similar group of patients with squamous cell carcinoma. Sixty of the group of 105 patients had excision biopsies of the neck node and this did not affect survival.     

Therapeutic selective neck dissection: a 25-year review

OBJECTIVES/HYPOTHESIS: The aim of the study was to show the efficacy of selective neck dissection in combination with postoperative radiation therapy in controlling squamous cell carcinoma metastatic to the cervical lymph nodes. The study compared the incidence of recurrences and overall disease-free survival between comparable cohorts undergoing a selective neck dissection and classic radical or modified neck dissection. STUDY DESIGN: Retrospective, 25-year review was made of data from a tertiary care academic facility comprising both private patients and veterans. METHODS: Inclusion criteria studied patients with untreated head and neck cancer who had squamous carcinoma metastatic to cervical lymph nodes on histological examination and were treated with a selective (n = 61), modified (n = 54), or radical neck dissection (n = 61). The three groups were compared with respect to regional control and overall cancer-free survival. All patients remained cancer free at the primary site, received postoperative radiation therapy, and had a minimum follow-up of 2 years. The median follow-up was 4.3 years. RESULTS: Control of recurrent carcinoma in the neck, as well as the incidence of overall cancer-free survival, was comparable in the three cohorts with no significant statistical difference. Eight of 176 sides of the necks (4.5%) showed evidence of recurrence (2 of 61 [3.3%] in the selective neck dissection group and 6 of 115 [5.2%] in the radical and modified neck dissection group. Disease-free 2-year survival was 80% in the selective neck dissection group and 64% in the radical and modified neck dissection group. CONCLUSION: Selective neck dissection, when used in combination with postoperative radiation therapy, is an efficacious way to manage metastatic squamous cell carcinoma to the neck.     

Managing regional metastasis in patients with cutaneous head and neck melanoma – is selective neck dissection appropriate?

Background

Neck dissection is recommended for patients with head and neck cutaneous melanoma and nodal metastasis. However, there appears to be no clear evidence to guide the extent of nodal resection.

Methods

Loco-regional recurrence (LR), overall survival (OS) and progression free survival (PFS) was retrospectively compared between patients who had Comprehensive neck dissection (CND) and Selective neck dissection (SND).

Results

There was no difference in LR, OS and PFS between CND (n = 18) and SND groups (n = 79). Extra capsular extension (ECE), frontal disease and increasing number of involved nodes resulted in worse OS and PFS but had no impact on LR.

Conclusion

Patients with disease limited to one node without ECE can be effectively treated by SND alone. In patients who have these unfavourable pathological features more extensive nodal resection does not improve outcome if they receive radiotherapy. Extent of neck dissection or adjuvant radiotherapy has no impact on overall survival.     

Treatment of oropharyngeal carcinoma by irradiation or by surgery

Of previously untreated patients with squamous cell carcinoma of the oropharynx, 145 are reviewed in this study. All were treated in the Department of Head and Neck Surgery at the University of Liverpool from 1990 to 1997. Seventy-seven patients were treated with irradiation, 28 patients by surgery and 40 patients were deemed not suitable for any curative treatment. Univariate analysis showed no difference in the two groups treated by curative modalities but multivariate analysis did suggest that the surgical group tended to have larger neck node metastases. The 5-year tumour specific actuarial survival for all patients was 53%, 65% for the radiotherapy group and 51% for the surgery group. The difference was not statistically significant (χ²₁ = 1.5070). The modality of treatment had no affect on either the development of a primary or neck node recurrence or the survival after such a recurrence. Where neck node disease was present it was treated as appropriate. As is generally standard practice, lymph nodes over 2 cm were treated with radical neck dissection whether the patient was having irradiation therapy or surgery. If the patient was having irradiation therapy, the neck dissection was carried out before and irradiation after operation, both on the primary and on the neck, if appropriate. It is concluded that irradiation therapy in properly selected cases in combined head and neck clinics is a safe and effective treatment for squamous cell carcinoma of the oropharynx. Neck node disease should be treated appropriately, but there is no support for the old adage that whatever form of treatment is being used for the neck node should also be used for the primary site.     

The significance of immunohistochemically demonstrated nodal micrometastases in patients with squamous cell carcinoma of the head and neck

OBJECTIVES/HYPOTHESIS: Patients with primary squamous cell carcinoma of the head and neck have a relatively high risk of occult lymph node metastases. Pathological demonstration of these metastases may be difficult, and the detection of such occult metastases may identify patients who are at an increased risk for early recurrence or reduced survival. Immunohistochemistry may be applied in the identification of occult metastases that may be missed on routine (H&E) histological examination. The aim of the study is to determine the prevalence and prognostic significance of immunohistochemically identified micrometastases in squamous cell carcinoma of the head and neck. STUDY DESIGN: A retrospective analysis of neck dissection specimens having no evidence of metastatic disease. METHODS: Lymph nodes from neck dissections performed on 10 patients with squamous cell carcinoma of the head and neck without conventional histological evidence of nodal metastases were subsequently stained for cytokeratins by the monoclonal antibody cocktail AE1/AE3 to detect micrometastases. RESULTS: Occult micrometastases were found in the lymph nodes 5 of 10 patients examined. There was no association between the site of primary tumor, or T tage, and the presence of occult metastases. Three of five patients found to have occult metastases developed recurrence in the neck, whereas only one of five patients with no evidence of micrometastases had regional recurrence. There was no significant discrepancy in the patient survival rate. CONCLUSIONS: Metastatic tumor cells are frequently present in lymph nodes, even in patients without histological evidence of nodal metastases by conventional methods. The presence of micrometastases may identify patients at increased risk for recurrence and may indicate poorer prognosis. The true clinical significance of these occult metastases will be determined by a long-term follow-up.     

Implications of tumour in resection margins following surgical treatment of squamous cell carcinoma of the head and neck

Presence of tumour at the resection margin following primary surgical treatment for squamous cell carcinoma of the head and neck is thought to adversely affect prognosis. To confirm this we performed a review of 478 patients treated by primary surgery for squamous cell carcinoma of the head and neck and sub-divided them into those exhibiting postive margins and those with negative margins following resection. Uni-variate and multi-variate statistical methods were used to analyse survival figures and a variety of parameters associated with the presence of positive resection margins. We found 5-year survival was decreased if resection margins were found to be positive (P < 0.025). The presence of positive resection margins was also significantly associated with time to tumour recurrence (P < 0.001) and survival with nodal recurrence (P < 0.001). Other factors which were significantly associated with survival using Cox's multi-variate analysis were site of tumour (P < 0.005), nodal extracapsular rupture (P < 0.05) and pathological T-stage (P < 0.05). Uni-variate analysis revealed no significant associations betweent the presence of positive margins and the patient's age, sex, tumour site, degree of tumour differentiation, and nodal status, though using multiple logistic regression, the general condition of the patient (P < 0.01) and the tumour site P < 0.05) were significantly related. The results support the concept that every effort should be made to obtain negative resection margins when undertaking primary ablative surgery for squamous cell carcinoma of the head and neck.     

Malignant melanoma of the scalp.

Malignant melanoma of the scalp has a significantly worse prognosis than cutaneous melanoma arising in other head and neck sites. In this series, 125 patients were treated for Stage I invasive melanoma of the scalp and followed 3 to 19 years. Survival rates for these patients were calculated on the basis of several factors. Survival after treatment was not affected by the age and sex of the patient, size and site of the primary, or treatment of the primary lesion, although local failure was higher among those treated by primary excision and closure. Patients undergoing elective neck dissection with histologically negative nodes had significantly better survival rates than those with histologically positive nodes or patients in whom a neck dissection was not performed.     

Effect of tumour thickness and other factors on the risk of regional disease and treatment of the N0 neck in early oral squamous carcinoma

A high occult metastatic rate and a high regional recurrence rate are reported among patients with early oral squamous carcinoma; however, considerable controversy exists regarding the merits of elective neck dissection in this group. The purpose of the present study was to examine the influence of various histological factors on the risk of occult neck disease, neck conversion and recurrence among 63 patients with stage I and II oral cancer. Tumour thickness (P = 0.0175) and size (P = 0.023) were both significantly predictive of outcome. Among tumours of a given thickness, those with infiltrative margins also showed a tendency towards a poorer outcome; however, this was not significant (P = 0.0768). Patients undergoing elective neck dissection with pathological evidence of cervical metastases or with subsequent neck recurrence had a better 3-year survival (55%) than those developing neck conversion after primary neck observation (20%). Our data would suggest considering tumours greater than 5 mm in thickness or with infiltrative margins as potential candidates for elective neck treatment.     

Cervical lymph node metastases. Incidence and implications of extracapsular carcinoma

The incidence and prognostic significance of extracapsular spread (ECS) of tumor in cervical lymphatics was investigated. The surgical specimens from 349 patients treated for squamous cell carcinoma by radical neck dissection between 1978 and 1982 have been examined retrospectively. Follow-up data were available relative to recurrence rate, site of recurrence, and disease-free intervals. Fifty-nine percent of the patients with N1 cervical metastases had ECS. Patients were classified according to the histopathologic findings in the radical neck dissection specimens. The three groups identified were patients with normal nodes, patients with no ECS, and patients with ECS. The histopathologic evidence of ECS was associated with a statistically significant reduction in survival when compared with patients without ECS. The disease-free interval between treatment and the development of recurrent disease was shorter for patients with ECS than for patients with no ECS.