OBJECTIVES: This study aimed to evaluate the efficacy and long-term stability of tunnel technique (TUN) and coronally advanced flap (CAF) combined with connective tissue graft (CTG) in treating gingival recession. METHODS: Databases including PubMed, Web of Science, Embase, and CNKI were electronically searched to collect randomized controlled trial (RCT) of CAF+CTG compared to TUN+CTG in the treatment of Miller class Ⅰ or Ⅱ gingival recession on September 1, 2022. RESULTS: There were 8 RCTs with 305 patients (454 recession sites) participating. The results of the Meta-analysis revealed that, in terms of mean root coverage (MRC) of main indicators, no significant difference was found between the CAF group and the TUN group in both short- and long-term results, which were [MD: 1.45%, 95%CI (-2.93%, 5.82%), P=0.52] and [MD: -0.70%, 95%CI (-6.41%, 5.00%), P=0.81]. However, the CAF group outperformed the TUN group in the long term [MD: 5.69%, 95%CI (0.87%, 10.50%), P=0.02], and the results of complete root coverage (CRC) analysis were similar to those of MRC. In the short term, the TUN group grew keratinized gingiva significantly faster than the CAF group [MD: -0.38 mm, 95%CI (-0.67 mm, -0.10 mm), P=0.008]. Long-term findings revealed no significant difference between the two groups [MD: -0.26 mm, 95%CI (-0.94 mm, 0.43 mm), P=0.46]. The TUN group's secondary index root coverage esthetic score (RES) was statistically significantly higher than the CAF group's [MD: 0.62, 95%CI (0.28, 0.96), P=0.000 3]. Given that there were few results included in the literature and the heterogeneity was too great, no significant difference was observed in the postoperative VAS pain index score [MD: 0.53, 95%CI (-1.96, 3.03), P=0.68]. CONCLUSIONS This study discovered that both CAF+CTG and TUN+CTG can achieve good root coverage in treating gingival recession, with CAF outperforming TUN and both groups achie-ving good long-term stability. After the operation, the TUN group had a higher RES than the CAF group. Given the limitations of this study, more high-quality studies are needed in the future to demonstrate the efficacy of TUN in gingival retraction surgery.
Humans ; Gingival Recession/surgery* ; Treatment Outcome ; Tooth Root ; Esthetics, Dental ; Gingiva/surgery*

Objective:To investigate the correlation between state-trait anxiety levels and quality of life before and after orthognathic surgery in patients with dentofacial deformities, and explore the feasibility of using the state-trait anxiety inventory(STAI) to screen postoperative patients with low quality of life.Methods:Patients with dentofacial deformities who underwent orthognathic surgery in Peking University Stomatological Hospital from September 2019 to March 2021 were selected as the research objects. STAI [including state anxiety inventory(SAI) and trait anxiety inventory(TAI)] and orthognathic quality of life questionnaire(OQLQ) were used to investigate patients before surgery, 2 weeks after surgery, 3 months after surgery and 6 months after surgery. The total scores of SAI and TAI ranged from 20 to 80 points, with higher scores implying a higher level of state-trait anxiety. The OQLQ includes four dimensions: social function, facial aesthetics, oral function and aesthetic perception, with total scores ranging from 22 to 88, higher scores representing a lower life quality level. SPSS 26.0 software used for statistical analysis, the measurement data was expressed as Mean±SD. Repeated measures ANOVA and the Bonferroni method were used to compare the SAI, TAI and OQLQ scores in different periods. Pearson correlation analysis was used to explore the correlation between patients’ demographic characteristics (gender, age, diagnostic classification, education, number of social contacts) and state-trait anxiety level, and life quality level at different periods, as well as the correlation between the state-trait anxiety level and the life quality level over time. Receiver operator characteristic(ROC) curve analysis was used to explore the feasibility of using the preoperative STAI scale to screen postoperative patients with low quality of life.Results:A total of 96 patients were included in this study, including 26 males and 70 females, aged (26.0±5.8) years. The SAI, TAI, and OQLQ total scores decreased during three postoperative periods compared to preoperative period ( P<0.01), indicating that the patients’ postoperative state-trait anxiety level decreased and their life quality level improved after surgery. Pearson correlation analysis showed a negative correlation between the patient’s social contact number and their SAI and TAI scores at postoperative 2 weeks (SAI: r=-0.30, P=0.003; TAI: r=-0.35, P<0.001). SAI and TAI scores were positively correlated in different periods ( r=0.48-0.84, P<0.01). Preoperative SAI scores and TAI scores were correlated with preoperative social function, aesthetic perception, facial aesthetic scores and total OQLQ scores (SAI: r=0.39-0.52, P<0.01; TAI: r=0.32-0.51, P<0.01). Preoperative SAI scores were positively correlated with social function and aesthetic perception scores and total OQLQ scores at 2 weeks postoperatively and with aesthetic perception, social function at 6 months postoperatively ( r=0.20-0.52, P<0.05 or <0.01). Postoperative SAI scores were positively correlated with OQLQ scores in all dimensions and total scores except for oral function scores at 3 months postoperatively, which were not correlated with the same period ( r= 0.24-0.55, P<0.05 or <0.01). Preoperative TAI scores were positively correlated with social function scores at 2 weeks( r=0.36, P<0.001) and 3 months( r=0.21, P=0.041) postoperatively. Postoperative TAI scores were positively correlated with OQLQ scores in all dimensions and total scores except for oral function scores at 2 weeks postoperatively, which were not correlated with oral function scores at the same period ( r=0.21-0.58, P<0.05 or <0.01). ROC curve analysis showed that preoperative SAI scores >34.5 and >33.5 screened people with low life quality level at postoperative 3 months and 6 months, with an area under the curve (AUC) of 0.75 (95% CI: 0.62-0.87, P=0.001) and 0.71 (95% CI: 0.59-0.84, P=0.003), respectively. Preoperative TAI scores >43.5, >42.5 and >33.5 can screen patients with low quality of life at 2 weeks, 3 months and 6 months after surgery, with AUC of 0.64(95% CI: 0.52-0.75, P=0.046), 0.73(95% CI: 0.60-0.85, P=0.001)and 0.67(95% CI: 0.55-0.80, P=0.016)respectively. Conclusion:The preoperative and postoperative state-trait anxiety level of patients with dentofacial deformity is correlated with the overall level of quality of life, social function, aesthetic perception and facial aesthetics. The preoperative application of STAI scale can screen patients with low quality of life after orthognathic surgery.

Objective:To investigate the correlation between state-trait anxiety levels and quality of life before and after orthognathic surgery in patients with dentofacial deformities, and explore the feasibility of using the state-trait anxiety inventory(STAI) to screen postoperative patients with low quality of life.Methods:Patients with dentofacial deformities who underwent orthognathic surgery in Peking University Stomatological Hospital from September 2019 to March 2021 were selected as the research objects. STAI [including state anxiety inventory(SAI) and trait anxiety inventory(TAI)] and orthognathic quality of life questionnaire(OQLQ) were used to investigate patients before surgery, 2 weeks after surgery, 3 months after surgery and 6 months after surgery. The total scores of SAI and TAI ranged from 20 to 80 points, with higher scores implying a higher level of state-trait anxiety. The OQLQ includes four dimensions: social function, facial aesthetics, oral function and aesthetic perception, with total scores ranging from 22 to 88, higher scores representing a lower life quality level. SPSS 26.0 software used for statistical analysis, the measurement data was expressed as Mean±SD. Repeated measures ANOVA and the Bonferroni method were used to compare the SAI, TAI and OQLQ scores in different periods. Pearson correlation analysis was used to explore the correlation between patients’ demographic characteristics (gender, age, diagnostic classification, education, number of social contacts) and state-trait anxiety level, and life quality level at different periods, as well as the correlation between the state-trait anxiety level and the life quality level over time. Receiver operator characteristic(ROC) curve analysis was used to explore the feasibility of using the preoperative STAI scale to screen postoperative patients with low quality of life.Results:A total of 96 patients were included in this study, including 26 males and 70 females, aged (26.0±5.8) years. The SAI, TAI, and OQLQ total scores decreased during three postoperative periods compared to preoperative period ( P<0.01), indicating that the patients’ postoperative state-trait anxiety level decreased and their life quality level improved after surgery. Pearson correlation analysis showed a negative correlation between the patient’s social contact number and their SAI and TAI scores at postoperative 2 weeks (SAI: r=-0.30, P=0.003; TAI: r=-0.35, P<0.001). SAI and TAI scores were positively correlated in different periods ( r=0.48-0.84, P<0.01). Preoperative SAI scores and TAI scores were correlated with preoperative social function, aesthetic perception, facial aesthetic scores and total OQLQ scores (SAI: r=0.39-0.52, P<0.01; TAI: r=0.32-0.51, P<0.01). Preoperative SAI scores were positively correlated with social function and aesthetic perception scores and total OQLQ scores at 2 weeks postoperatively and with aesthetic perception, social function at 6 months postoperatively ( r=0.20-0.52, P<0.05 or <0.01). Postoperative SAI scores were positively correlated with OQLQ scores in all dimensions and total scores except for oral function scores at 3 months postoperatively, which were not correlated with the same period ( r= 0.24-0.55, P<0.05 or <0.01). Preoperative TAI scores were positively correlated with social function scores at 2 weeks( r=0.36, P<0.001) and 3 months( r=0.21, P=0.041) postoperatively. Postoperative TAI scores were positively correlated with OQLQ scores in all dimensions and total scores except for oral function scores at 2 weeks postoperatively, which were not correlated with oral function scores at the same period ( r=0.21-0.58, P<0.05 or <0.01). ROC curve analysis showed that preoperative SAI scores >34.5 and >33.5 screened people with low life quality level at postoperative 3 months and 6 months, with an area under the curve (AUC) of 0.75 (95% CI: 0.62-0.87, P=0.001) and 0.71 (95% CI: 0.59-0.84, P=0.003), respectively. Preoperative TAI scores >43.5, >42.5 and >33.5 can screen patients with low quality of life at 2 weeks, 3 months and 6 months after surgery, with AUC of 0.64(95% CI: 0.52-0.75, P=0.046), 0.73(95% CI: 0.60-0.85, P=0.001)and 0.67(95% CI: 0.55-0.80, P=0.016)respectively. Conclusion:The preoperative and postoperative state-trait anxiety level of patients with dentofacial deformity is correlated with the overall level of quality of life, social function, aesthetic perception and facial aesthetics. The preoperative application of STAI scale can screen patients with low quality of life after orthognathic surgery.

Objective:To evaluate the three-dimensional soft tissue changes at nasolabial region of female patients with maxillary protrusion after orthognathic surgery with maxillary setback.Methods:Peking University School and Hospital of Stomatology admitted 88 female patients with maxillary protrusion, aged 18-42 years old, with an average age of 28.2 years old. The segmental Le Fort Ⅰ osteotomies were performed in all patients with extraction of maxillary first premolars to create space for maxillary setback. The patients with maxillary protrusion and mandibular retraction received bilateral sagittal split ramus osteotomy(BSSRO)to move mandibular body, while the patients with bimaxillary protrusion received subapical osteotomy. 3dMD photos were taken preoperative 1-3 days and at least 6 months after operation to obtain three-dimensional facial images. The postoperative soft tissue changes of three-dimensional landmarks, line space and angles were measured with the use of Geomagic Studio 2013, and three-dimensional deviation analysis was applied. Paired t test was performed on the measured results. P<0.05 was considered statistically significant. Results:The distance of the subnasale in sagittal direction in patients with maxillary protrusion was (-10.90±18.60) mm preoperatively, (-10.05±18.62) mm ( t=-7.66, P<0.001)postoperatively, and setback of (0.85±1.00) mm; Labrale superius was (-15.18±18.67) mm preoperatively, (-11.92±18.9) mm postoperatively, and setback of (3.26±1.40) mm. Preoperative nasal width was (37.32±2.32) mm, postoperative for (38.08±2.32) mm ( t=-4.85, P<0.001)and increased by (0.76±1.47) mm.The lip width was (49.17±3.54) mm before surgery and (47.68±3.74) mm ( t=5.77, P<0.001)after surgery ( t=5.77, P<0.001), decreased by (1.49±2.42) mm. Philtrum length was (15.20±2.32) mm preoperatively and (15.78±2.17) mm ( t=-4.70, P<0.001)postoperatively, increased by (0.58±1.16) mm; The nasolabial angle was 101.98°±9.34° before surgery and 109.05°±8.59° ( t=-12.36, P<0.001)after surgery, increased by 6.99°±5.35°. The three-dimensional deviation analysis result showed that the soft tissue in the parasnasal area was moved forward (1.54±0.73) mm. Conclusions:3dMD can reflect the three-dimensional soft tissues changes after orthognathic surgery directly and accurately. After maxillary setback, the nasal base and upper lip of patients were significantly retrograded, and the paranasal area appeared forward, accompanied by increase in the nasolabial angle, lengthening of the philtrum length, vermillion length decrease, increase in nasal width and decrease in lip width.

Objective:To evaluate the three-dimensional soft tissue changes at nasolabial region of female patients with maxillary protrusion after orthognathic surgery with maxillary setback.Methods:Peking University School and Hospital of Stomatology admitted 88 female patients with maxillary protrusion, aged 18-42 years old, with an average age of 28.2 years old. The segmental Le Fort Ⅰ osteotomies were performed in all patients with extraction of maxillary first premolars to create space for maxillary setback. The patients with maxillary protrusion and mandibular retraction received bilateral sagittal split ramus osteotomy(BSSRO)to move mandibular body, while the patients with bimaxillary protrusion received subapical osteotomy. 3dMD photos were taken preoperative 1-3 days and at least 6 months after operation to obtain three-dimensional facial images. The postoperative soft tissue changes of three-dimensional landmarks, line space and angles were measured with the use of Geomagic Studio 2013, and three-dimensional deviation analysis was applied. Paired t test was performed on the measured results. P<0.05 was considered statistically significant. Results:The distance of the subnasale in sagittal direction in patients with maxillary protrusion was (-10.90±18.60) mm preoperatively, (-10.05±18.62) mm ( t=-7.66, P<0.001)postoperatively, and setback of (0.85±1.00) mm; Labrale superius was (-15.18±18.67) mm preoperatively, (-11.92±18.9) mm postoperatively, and setback of (3.26±1.40) mm. Preoperative nasal width was (37.32±2.32) mm, postoperative for (38.08±2.32) mm ( t=-4.85, P<0.001)and increased by (0.76±1.47) mm.The lip width was (49.17±3.54) mm before surgery and (47.68±3.74) mm ( t=5.77, P<0.001)after surgery ( t=5.77, P<0.001), decreased by (1.49±2.42) mm. Philtrum length was (15.20±2.32) mm preoperatively and (15.78±2.17) mm ( t=-4.70, P<0.001)postoperatively, increased by (0.58±1.16) mm; The nasolabial angle was 101.98°±9.34° before surgery and 109.05°±8.59° ( t=-12.36, P<0.001)after surgery, increased by 6.99°±5.35°. The three-dimensional deviation analysis result showed that the soft tissue in the parasnasal area was moved forward (1.54±0.73) mm. Conclusions:3dMD can reflect the three-dimensional soft tissues changes after orthognathic surgery directly and accurately. After maxillary setback, the nasal base and upper lip of patients were significantly retrograded, and the paranasal area appeared forward, accompanied by increase in the nasolabial angle, lengthening of the philtrum length, vermillion length decrease, increase in nasal width and decrease in lip width.

Objective: The clinical application of free perforator flaps in aesthetic repairing of the wounds of electric injuries in forearms and palms. Methods: 20 cases of skin tissue defects of electric injuries in forearms and palms were collected in this group, including 18 male patients and 2 female patients ranged from 20 to 50 years. The size of the skin defects are from 7 cm×5 cm to 18 cm×8 cm. 20 cases of forearms and palms with electric injuries, all of which were repaired by the transplantation of free musculocutaneous perforator monoflaps with anastomosis of interregional blood vessels. 10 cases of wounds in forearms were treated with lateral femoral circumflex artery perforator flaps with sensate nerves. The other 10 cases of wounds in palms were treated with medial plantar artery perforator flap with sensate nerves, with a flap area of 8 cm× 6cm to 20 cm×9 cm. In the donor area, 10 cases were closed with aesthetic suture and 10 cases were repaired with skin grafts. Results: All flaps survived in 20 cases. Artery crisis was found in 1 case on the second day after surgery, and this flap with anastomosis of blood vessels also survived after surgical exploration without delay. The shapes and functions of palms and forearms were observed basically restored from a aesthetic point of view from a follow-up of 3 months to 36 months. Most touch, pain and warm senses were restored in cases with sensate nerves. And a two-point discrimination was 9—11 mm. A satisfactory functional recovery was achieved. The donor sites were found well-healed without any obvious scars or functional disorders. Conclusions Because of the advantages of hidden donor sites, reliable blood supply, closed texture and good abrasion-resistance, the multiple perforator sublobe flaps with sensate nerves could be adopted, and after thinning could be used as the free flaps to repair the wounds. These have predicted that this method is one of the desirable methods of aesthetic repairing and functional reconstruction of subunits skin tissue defects in palms and forearms.

Objective To explore the clinical significance of blood flow reserve fraction in the treatment of coronary stent implantation.Methods A total of 46 patients with positive coronary angiography were included.Criteria for positive coronary angiography:coronary angiography confirmed at least a coronary artery stenosis was more than or equal to 50%.According to the results,the patients were divided into the control group(24 cases) and observation group(22 cases).Results 1.There was no significant difference in baseline level(P>0.05);2.The operation time,number of stents and the contrast agent dosage of the observation group were (63.20±9.92)min,(0.50±0.65) and (182.94±39.30)mL,which were significantly less than those of the control group,the differences were statistically significant(operation time t=2.69,P=0.01;number of stents t=2.56,P=0.02;contrast agent dosage t=6.98,P=0.00).There was no significant difference between the control group and the observation group in angina pectoris and MACE attack.Conclusion Blood flow reserve score is an important guiding parameter for PCI treatment of coronary artery stenosis.

Objective To quantitatively analyze the changes of facial symmetry and temporomandibular joint structure at different periods after intraoral condylectomy combined with orthognathic surgery,and to evaluate the long-term stability after the operation.Methods Spiral CT data of 10 cases treated by intraoral condylectomy combined with orthognathic surgery were collected,and then reconstructed by ProPlan software.Mark points were drawn on the 3D-images reconstructed immediately after the operation,and 6 months and 12 months after the operation.The measurements parameters included condylar axis angle in three dimensions,condylar-glenoid relative position and condylar facial morphology related indicators.The results were statistically analyzed by the consistency test and the variance of repeated measurement data.Results The facial asymmetry of the patients was corrected after operation,the height of the affected mandibular ascending ramus(T1:[67.81±6.95] mm,T2:[64.49±6.24] mm,T3:[63.05±7.07] mm) as well as the degree of pogonion deviation decreased(T1:[2.79±4.93] mm,T2:[0.37±4.20] mm,T3:[0.33 ± 3.97] mm) (P＜0.05).But the tilt angle of the occlusion plane and the degree of mandibular height asymmetry had no significant difference between all the post-operative periods(P＞0.05).The post-operative 3D changes of the position and shape of the resected and its contralateral condylar showed that the bilateralcondylar axis angle in the horizontal plane gradually grew after operation(affected condyle:71.95°±7.47°,74.73°±8.44°,76.56°±5.22°;control condyle:72.60°±5.56°,76.00°±5.30°,77.19°±6.20° and had significant difference between all the post-operative periods)(P＜0.05),the condyle moved slowly upward on both sides (superior space on the affected side:[8.78±4.38] mm,[4.11±2.49] mm,[3.27±1.96] mm;on the control side:[3.63t1.49] mm,[2.52±1.19] mm,[2.38±1.11] mm)(P＜0.05),and moved inward only on the affected side(P＜0.05).All the above changes slowed down over time,and the disc-condyle-fossa relative position tended to be stable over time as well.The condyle diameter on the inside-outside direction gradually decreased on the affected side(T1:[14.98±2.39] mm,T2:[14.04±2.68] mm,T3:[13.74±2.89] mm)(P＜0.05),and the surface morphology,of the resected condyle was similar to the normal side.There were also some condylar surface morphological changes on the control side,but no statistical significance was found between different periods after the peration(P＞0.05).Conclusions The intraoral condylectomy combined with orthognathic surgery can eliminate condylar lesions effectively and correct the facial asymmetry caused by condylar benign tumor and hyperplasia.The facial symmetry can be maintained well after the operation,and the post-operative condylar morphology changes tended to be stable six months after the operation.

Objective To explore the efficiency and adverse effects of the effective EP ( etoposide+cisplatin) therapy and its subsequent maintenance therapy with different durations in patients with small cell lung cancer ( SCLC ) . Methods Clinical data of 104 SCLC patients diagnosed and treated at the Jilin Province Cancer Hospital between September 2010 and December 2013 were retrospectively analyzed.Among them, 35 patients were subsequently treated with a 4?week maintenance therapy following the original therapeutic regimen after the effective EP therapy (4?week maintenance therapy group), 35 patients were treated with a subsequent 6?week maintenance therapy ( 6?week maintenance therapy group ) , and 34 patients were treated without maintenance therapy ( control group) .52 patients were in limited stage, and 52 patients were in extensive stage. The progression?free survival (PFS), overall survival (OS) and adverse effects in the 4?week maintenance therapy group, 6?week maintenance therapy group and control group were analyzed. Results The median PFS in the control group, 4?week maintenance therapy group and 6?week maintenance therapy group was 4.0, 3.5, and 4.0 months, respectively, and the median OS was 9.0, 10.0 and 12.0 months, respectively, showing no significant difference among the groups (P>0.05 for all). The median PFS was prolonged by 2 months as compared with the control group after the 4?week maintenance therapy in the patients with complete remission in first?line chemotherapy ( P=0.041) , while the median OS was not improved ( P=0. 131). Neither the median PFS nor median OS showed statistically significant difference between each two groups in the patients with partial remission in first?line chemotherapy ( P>0.05 for all) . In the limited stage, the median PFS in the control group, 4?week maintenance therapy group, and 6?week maintenance therapy group was 5.0, 6.5, and 4.0 months, respectively, and median OS was 11.0, 13.5, and 13.0 months, respectively, the differences showed no statistical significance ( P>0.05 for all) . In the extensive stage, the median PFS in the control group, 4?week maintenance therapy group, and 6?week maintenance therapy group was 3.0, 3.0, and 3.5 months, respectively, showing significant differences ( P=0.015);the median OS was 6.5, 8.0, and 8.0 months, respectively, presenting no statistically significant differences (P=0.096). In addition, the PFS in the 6?week maintenance therapy group was significantly improved as compared with that in the control group ( P=0. 016 ) . Compared with the control group, the incidence rates of nausea ( grade 3?4 ) , vomiting, hypodynamia, leukopenia, neutropenia, and thrombocytopenia in the 4?week maintenance therapy group and 6?week maintenance therapy group were increased significantly ( P<0.05 for all) , however, the side effects were tolerable. Conclusion Prolonging the treatment cycle of EP therapy can improve the PFS in SCLC patients in first?line CR chemotherapy and extensive stage.

Objective To explore the efficiency and adverse effects of the effective EP ( etoposide+cisplatin) therapy and its subsequent maintenance therapy with different durations in patients with small cell lung cancer ( SCLC ) . Methods Clinical data of 104 SCLC patients diagnosed and treated at the Jilin Province Cancer Hospital between September 2010 and December 2013 were retrospectively analyzed.Among them, 35 patients were subsequently treated with a 4?week maintenance therapy following the original therapeutic regimen after the effective EP therapy (4?week maintenance therapy group), 35 patients were treated with a subsequent 6?week maintenance therapy ( 6?week maintenance therapy group ) , and 34 patients were treated without maintenance therapy ( control group) .52 patients were in limited stage, and 52 patients were in extensive stage. The progression?free survival (PFS), overall survival (OS) and adverse effects in the 4?week maintenance therapy group, 6?week maintenance therapy group and control group were analyzed. Results The median PFS in the control group, 4?week maintenance therapy group and 6?week maintenance therapy group was 4.0, 3.5, and 4.0 months, respectively, and the median OS was 9.0, 10.0 and 12.0 months, respectively, showing no significant difference among the groups (P>0.05 for all). The median PFS was prolonged by 2 months as compared with the control group after the 4?week maintenance therapy in the patients with complete remission in first?line chemotherapy ( P=0.041) , while the median OS was not improved ( P=0. 131). Neither the median PFS nor median OS showed statistically significant difference between each two groups in the patients with partial remission in first?line chemotherapy ( P>0.05 for all) . In the limited stage, the median PFS in the control group, 4?week maintenance therapy group, and 6?week maintenance therapy group was 5.0, 6.5, and 4.0 months, respectively, and median OS was 11.0, 13.5, and 13.0 months, respectively, the differences showed no statistical significance ( P>0.05 for all) . In the extensive stage, the median PFS in the control group, 4?week maintenance therapy group, and 6?week maintenance therapy group was 3.0, 3.0, and 3.5 months, respectively, showing significant differences ( P=0.015);the median OS was 6.5, 8.0, and 8.0 months, respectively, presenting no statistically significant differences (P=0.096). In addition, the PFS in the 6?week maintenance therapy group was significantly improved as compared with that in the control group ( P=0. 016 ) . Compared with the control group, the incidence rates of nausea ( grade 3?4 ) , vomiting, hypodynamia, leukopenia, neutropenia, and thrombocytopenia in the 4?week maintenance therapy group and 6?week maintenance therapy group were increased significantly ( P<0.05 for all) , however, the side effects were tolerable. Conclusion Prolonging the treatment cycle of EP therapy can improve the PFS in SCLC patients in first?line CR chemotherapy and extensive stage.