The prognostic and predictive significance of perineural invasion in stage I to III colon cancer: a propensity score matching-based analysis.

BACKGROUND: Colorectal cancer (CRC) presents with varying prognoses, and identifying factors for predicting metastasis and outcomes is crucial. Perineural invasion (PNI) is a debated prognostic factor for CRC, particularly in stage I-III patients, but its role in guiding adjuvant chemotherapy for node-positive colon cancer remains uncertain. METHODS: We conducted a single-center study using data from the Colorectal Section Tumor Registry Database at Chang Gung Memorial Hospital, Taiwan. This prospective study involved 3,327 CRC patients, 1,536 of whom were eligible after application of the exclusion criteria, to investigate the prognostic value of PNI in stage I-III patients and its predictive value for node-positive/negative cancer patients receiving adjuvant chemotherapy. Propensity score matching (PSM) was used to minimize selection bias, and follow-up was performed with standardized procedures. RESULTS: PNI-positive (PNI+) tumors were associated with higher preoperative CEA levels and more frequent adjuvant chemotherapy. After PSM, PNI + tumors were associated with marginally significantly lower 5-year disease-free survival (DFS) and significantly lower overall survival (OS) rates in stages III CRC. However, no significant differences were observed in stages I and II. Subgroup analysis showed that among PNI + tumors, only poorly differentiated tumors had higher odds of recurrence. PNI did not predict outcomes in node-negative colon cancer. Adjuvant chemotherapy benefited PNI + patients with node-positive but not those with node-negative disease. CONCLUSIONS: Our study indicates that PNI is an independent poor prognostic factor in stage III colon cancer but does not predict outcomes in node-negative disease. Given the potential adverse effects of adjuvant chemotherapy, our findings discourage its use in node-negative colon cancer when PNI is present.

Venous Size Discrepancy Is a Critical Factor When Using Superficial Temporal Vessels as Recipient Vessels for Free Flaps.

BACKGROUND: Superficial temporal vessels have been used successfully as recipient vessels for head and neck reconstruction. This study evaluates the impact of several treatment variables on flap failure and take-back rate when using these recipient vessels. METHODS: We conducted a retrospective study of all microsurgical reconstructions using superficial temporal vessels as recipient vessels in a period of 10 years. Variables collected included previous treatments (radiotherapy, chemotherapy, neck dissection, free flap reconstruction), type of flaps used (soft tissue, osteocutaneous), and vessel size discrepancy between donor and recipient vessels. RESULTS: A total of 132 patients were included in the study. The flap success rate was 98.5%. The take-back rate was 10.6%. The most frequent reason for take-back was venous congestion secondary to thrombosis. None of the studied variables was associated with flap failure. Reconstructions using osteocutaneous flaps and vein diameter discrepancy (ratio ≥ 2:1) had significantly higher take-back rates. CONCLUSION: Flaps with a significant size discrepancy between donor and recipient veins (ratio ≥ 2:1) and fibula flaps (compared with soft tissue flaps) were associated with a higher risk of take-back. It is crucial to minimize venous engorgement during flap harvest and anastomosis, and limit vein redundancy during flap in-setting.

Hypoxia-induced epithelial-mesenchymal transition and fibrosis for the development of breast capsular contracture.

Fibrosis has been considered as a major cause of capsular contracture. Hypoxia has widely emerged as one of the driving factors for fibrotic diseases. The aim of this study was to examine the association between hypoxia-induced fibrosis and breast capsular contracture formation. Fibrosis, epithelial-mesenchymal transition (EMT), expression levels of hypoxia-inducible factor-1α (HIF-1α), vimentin, fibronectin, and matrix metalloproteinase-9 (MMP-9) in tissues from patients with capsular contracture were determined according to the Baker classification system. Normal breast skin cells in patients with capsular contracture after implant-based breast surgery and NIH3T3 mouse fibroblasts were cultured with cobalt chloride (CoCl2) to mimic hypoxic conditions. Treatment responses were determined by detecting the expression of HIF-1α, vimentin, fibronectin, N-cadherin, snail, twist, occludin, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1) and -2, as well as phosphorylated ERK. The expression levels of HIF-1α, vimentin, fibronectin, and fibrosis as well as EMT were positively correlated with the severity of capsular contracture. MMP-9 expression was negatively correlated the Baker score. Hypoxia up-regulated the expression of HIF-1α, vimentin, fibronectin, N-cadherin, snail, twist, TIMP-1 and -2, as well as phosphorylated ERK in normal breast skin cells and NIH3T3. Nonetheless, the expression levels of MMP-9 and occludin were down-regulated in response to CoCl2 treatment. This study is the first to demonstrate the association of hypoxia-induced fibrosis and capsular contracture.

Predictors for Reconstruction and Mood Disorder Associated With Reconstruction in Patients With Breast Cancer and Mastectomy: A Retrospective Cohort Study.

This study used Taiwan's National Health Insurance medical claims to investigate the predictors for operative modes chosen by early-stage breast cancer patients; as well as to assess whether operative modes are associated with risk of mood disorder. We included 36,377 patients with breast cancer who received surgery between 2000 and 2008, and were followed to the end of 2010; they were further classified into 3 groups: mastectomy alone (n = 34,900), along with early reconstruction (n = 1080), and along with delayed reconstruction (n = 397). The results showed that age, insurance premium, urbanization level, and postsurgery chemotherapy and radiotherapy were all significant predictors for the selection of operative modes. Breast cancer patients with mastectomy alone, early reconstruction, and delayed reconstruction showed a cumulative incidence rate of mood disorder of 36.90%, 41.56%, and 33.89%, respectively. The multiple cox proportional model further revealed that early (hazard ratio [HR] = 1.06, 95% confidence interval (CI) = 0.93-1.21) and delayed (HR = 1.17, 95% CI = 0.96-1.42) reconstruction were associated with a slightly higher but insignificant risk of mood disorder, as compared to the patients received no reconstruction.

The modified finger-trap suture technique: a biomechanical comparison of a novel suture technique for graft fixation.

PURPOSE: The purpose of this study was to compare the tendon graft holding power of the newly devised modified finger-trap (MFT) suture technique with other currently used sutures. METHODS: We used 40 fresh-frozen porcine flexor profundus tendons randomly divided into 4 groups of 10 specimens. The experimental procedure was designed to assess percent elongation of the suture-tendon construct across four different tendon-grasping techniques: MFT suture, Krackow stitch, locking SpeedWhip stitch (Arthrex, Naples, FL), and nonlocking SpeedWhip stitch. The suture configurations of the MFT suture and Krackow stitch were completed with a No. 2 FiberWire suture (Arthrex). The locking SpeedWhip and nonlocking SpeedWhip stitches were completed with a loop of No. 2 FiberWire suture and a FiberLoop needle (Arthrex). Each tendon was pre-tensioned to 100 N for three cycles and then cyclically loaded to 200 N for 200 cycles. Finally, each tendon was loaded to failure. Percent elongation, load to failure, and mode of failure for each suture-tendon construct were measured. RESULTS: During the pre-tension phase, the MFT suture had the smallest percent elongation (P = .021) of the suture-graft construct (13.5% ± 1.9%) compared with the Krackow (16.9% ± 1.2%), locking SpeedWhip (17.6% ± 0.6%), and nonlocking SpeedWhip (33.3% ± 5.6%) stitches. During cyclic loading, the MFT suture also showed a significantly smaller percent elongation (P = .037) of the suture-graft construct (27.8% ± 4.9%) than the Krackow (35.8% ± 5.4%), locking SpeedWhip (33.7% ± 5.4%), and nonlocking SpeedWhip (43.8% ± 7.8%) stitches. The load to failure and cross-sectional area were not significantly different across all the suture groups. CONCLUSIONS: The newly devised MFT suture provided better percent elongation and equal load to failure compared with the Krackow and SpeedWhip suture techniques tested in this in vitro biomechanical evaluation. CLINICAL RELEVANCE: The MFT suture is a simple method that is an attractive alternative to the Krackow and SpeedWhip suture techniques for tendon graft fixation in ligament reconstruction.

Reconstruction of a massive femoral bone defect using a double-barreled free vascularized fibular bone graft after wide resection of femoral chondrosarcoma.

Salvaging the limb after malignant bone tumor ablation is a tough challenge for a reconstructive surgeon confronting such extensive bone defects. A 40-year-old male without any underlying disease was incidentally diagnosed with a chondrosarcoma over his left femoral bone. An orthopedic surgeon did a wide resection of the malignant bone tumor, leaving a massive bone defect about 11.3 cm in length. A double-barreled free vascularized fibular bone was designed to reconstruct the femoral bone defect. The maximal fibular bone graft harvested was 19 cm long; after the osteotomy, one barrel was 11 cm and the other was 8 cm. An iliac crest cancellous bone graft was harvested to fill the residual space. The pathology report showed a grade 1 well-differentiated conventional chondrosarcoma, and further adjuvant therapy was not suggested. At a 3-year follow-up, plain radiography showed a good bony union of the graft, and the patient could easily tolerate daily activity. A vascularized double-barreled fibular graft is an ideal option for reconstructing a massive defect in weight-bearing bone: it provides not only sufficient mechanical strength but also good union for early rehabilitation. We describe the long-term results after reconstruction and provide a literature review of long-bone chondrosarcoma.