Prognostic Impact of Preoperative Osteosarcopenia for Patients with Pancreatic Ductal Adenocarcinoma After Curative Resection.

BACKGROUNDS: The clinical significance of preoperative osteosarcopenia in pancreatic ductal adenocarcinoma (PDAC) has not been fully studied. The purpose of this study was to evaluate the role of preoperative osteosarcopenia in predicting the survival of patients with PDAC. METHODS: We retrospectively analyzed 265 patients who underwent curative surgical resection for PDAC between 2012 and 2018 in two Japanese institutes. The skeletal muscle index at the L3 vertebrae and the bone mineral density at the Th11 vertebra were calculated for the evaluation of osteosarcopenia before surgery. The relationship between perioperative osteosarcopenia and clinicopathological factors and prognosis was analyzed. RESULTS: The median overall survival (OS) and disease-free survival (DFS) of patients with osteosarcopenia were significantly shorter than those of patients without osteosarcopenia (OS: 23 and 48 months, respectively, P < 0.001; DFS: 13.4 and 21.2 months, respectively, P = 0.004). On multivariate analysis, osteosarcopenia was found to be an independent factor associated with OS (hazard ratio [HR] 1.98; 95% confidence interval [CI] 1.40-2.80; P < 0.001) and DFS (HR 1.53; 95% CI 1.11-2.10; P = 0.009). CONCLUSIONS: Preoperative osteosarcopenia may be a useful prognostic factor in patients with PDAC who undergo surgical resection. Further studies are needed to assess whether perioperative, nutritional interventions and rehabilitation contribute to improving the prognosis of these patients.

A Prospective Multicenter Phase II Trial of Neoadjuvant Chemotherapy with Gemcitabine Plus Nab-Paclitaxel for Borderline Resectable Pancreatic Cancer with Arterial Involvement.

BACKGROUND: Only two clinical trials have shown the effects of neoadjuvant treatment for borderline resectable pancreatic cancer with arterial involvement (BRPC-A). Here, we aimed to analyze the efficacy and safety of neoadjuvant gemcitabine plus nab-paclitaxel (GnP) for BRPC-A. PATIENTS AND METHODS: A prospective, single-arm, multicenter phase II trial was conducted. Patients who were radiologically and histologically diagnosed with BRPC-A were enrolled. A central review was conducted to confirm the presence of BRPC-A. Patients received two to four cycles of GnP before surgery. The primary endpoint of the study was the R0 resection rate. Overall survival (OS) was evaluated in an ancillary study. RESULTS: Thirty-five patients were enrolled, of whom 33 were subjected to central review and 28 were confirmed to have BRPC-A. All eligible patients with BRPC-A received neoadjuvant GnP. Nineteen patients underwent pancreatic resections. Postoperative complications of Clavien-Dindo IIIa or lower were observed in 11 patients. No treatment-related mortalities were observed. R0 resection was achieved in 17 patients (89%); the R0 resection rate was 61% in eligible patients. One patient underwent curative resection after termination of the treatment protocol, resulting in an overall R0 resection rate of 64%. The median overall survival (OS) and 2-year OS rate were 24.9 months [95% confidence interval (CI) 19.0 months to not estimatable] and 53.6%, respectively. OS in patients with BRPC-A who achieved overall R0 resection was significantly longer than that in the other patients (p = 0.0255). CONCLUSIONS: Neoadjuvant GnP is a safe and effective strategy for BRPC-A, providing a chance for curative resection and improved survival.

High frequency of bone recurrence as an initial recurrence site after radical surgery in T1N3 gastric cancer: a propensity score matching analysis.

PURPOSE: T1 gastric cancer (GC) with seven or more metastatic lymph nodes is extremely rare, and very few clinical studies have been conducted to evaluate the clinicopathological features of their recurrence. METHODS: We retrospectively analyzed the outcomes of T1 GC and T2-4 GC patients who had multiple nodal metastases after radical surgery from 2006 to 2020. Propensity score matching was performed to compare the two groups of patients. RESULTS: After propensity score matching, 18 of 22 patients in the T1 group and 36 of 144 patients in the T2-4 group were selected. Recurrence occurred in six patients (33.3%) in the T1 group. In the T1 group, the most common site of initial recurrence was bone (15.0%). The prevalence of bone recurrence was significantly higher in the T1 group than in the T2-4 group (P = 0.02). The median interval time between radical surgery and bone recurrence was 24 months, and the median survival time after bone recurrence was 14 months. CONCLUSION: Bone recurrence was more frequently identified as an initial recurrence site in T1 GC cases with multiple metastases after radical surgery compared with that in T2-4 GC cases. Careful attention should be paid to postoperative bone recurrence in the long-term postoperative course of these patients.

Billroth-I reconstruction using an overlap method in totally laparoscopic distal gastrectomy: propensity score matched cohort study of short- and long-term outcomes compared with Roux-en-Y reconstruction.

BACKGROUND: Delta-shaped anastomosis is an established procedure for intracorporeal Billroth-I reconstruction (B-I). However, this procedure has several technical and economic problems. The aim of the current study was to present the technique of B-I using an overlap method (overlap B-I), which is a side-to-side intracorporeal gastroduodenostomy in laparoscopic distal gastrectomy (LDG), and to evaluate the short- and long-term outcomes of this overlap B-I procedure. METHODS: We retrospectively reviewed the medical records of 533 patients who underwent LDG with overlap B-I (n = 247) or Roux-en-Y reconstruction (R-Y) (n = 286). Patients with overlap B-I were propensity score matched to patients with R-Y in a 1:1 ratio. Short- and long-term outcomes of the two procedures were compared after matching. RESULTS: In the total cohort, anastomosis-related complications occurred in 2.4% of patients with overlap B-I, and 3.2% of those with R-Y (P = 0.794). Morbidity rate, including anastomosis-related complications, and postoperative course were comparable after overlap B-I performed by qualified versus general surgeons. Of 247 patients with overlap B-I, 169 could be matched. After matching, morbidity rate and postoperative course were comparable between the two procedures. Median operation time was significantly shorter for overlap B-I (205 min) than R-Y (252 min; P < 0.001). The incidence of readmission due to gastrointestinal complications was significantly lesser after overlap B-I (2.4%) compared with R-Y (21.9%; P < 0.001). The main causes of readmission after R-Y were bowel obstruction (7.3%) and gallstones (8.0%). Regarding the development of common bile duct (CBD) stones, 11 patients (3.8%) who underwent R-Y were readmitted due to CBD stones, whereas no patients who underwent B-I developed CBD stones. CONCLUSIONS: Overlap B-I is feasible and safe, even when performed by general surgeons. B-I was superior to R-Y concerning operation time and readmission due to gastrointestinal complications.

Significance of neoadjuvant therapy for borderline resectable pancreatic cancer: a multicenter retrospective study.

PURPOSE: Neoadjuvant therapy (NAT) is increasingly used to improve the prognosis of patients with borderline resectable pancreatic cancer (BRPC) albeit with little evidence of its advantage over upfront surgical resection. We analyzed the prognostic impact of NAT on patients with BRPC in a multicenter retrospective study. METHODS: Medical data of 165 consecutive patients who underwent treatment for BRPC between January 2010 and December 2014 were collected from ten institutions. We defined BRPC according to the National Comprehensive Cancer Network guidelines, and subclassified patients according to venous invasion alone (BR-PV) and arterial invasion (BR-A). RESULTS: The rates of NAT administration and resection were 35% and 79%, respectively. There were no significant differences in resection rates and prognoses between patients in the BR-PV and BR-A subgroups. NAT did not have a significant impact on prognosis according to intention-to-treat analysis. However, in patients who underwent surgical resection, NAT was independently associated with longer overall survival (OS). The median OS of patients who underwent resection after NAT (53.7 months) was significantly longer than that of patients who underwent upfront (17.8 months) or no resection (14.9 months). The rates of superior mesenteric or portal vein invasion, lymphatic invasion, venous invasion, and lymph node metastasis were significantly lower in patients who underwent resection after NAT than in those who underwent upfront resection despite similar baseline clinical profiles. CONCLUSIONS: Resection after NAT in patients with BRPC is associated with longer OS and lower rates of both invasion to the surrounding tissues and lymph node metastasis.

Long-Term Outcomes After Pancreatectomy for Pancreatic Ductal Adenocarcinoma in Elderly Patients: Special Reference to Postoperative Adjuvant Chemotherapy.

BACKGROUND: The benefit of pancreatectomy for elderly patients with pancreatic ductal adenocarcinoma (PDAC) remains controversial. Moreover, adjuvant chemotherapy (AC) for elderly patients has not been fully evaluated. We investigated the long-term outcomes after pancreatectomy for PDAC in elderly patients with special reference to AC. METHODS: The medical records of 123 patients who underwent pancreatectomy for PDAC from 2007 to 2016 were retrospectively reviewed. The patients were divided into two groups: young (<75 years) and elderly patients (≥75 years). RESULTS: The study population comprised 91 young and 32 elderly patients. The postoperative clinical courses were not different between the two groups. AC was more frequently administered to young (85%) than elderly patients (66%; P = 0.04). The weekly dose of tegafur/gimeracil/oteracil potassium (S1) for AC was significantly lower in elderly (median 423 mg/m2) than young patients (median 491 mg/m2; P = 0.02). The prevalence of adverse events and the completion rate of AC were not significantly different between the two groups. There were no significant differences in recurrence-free survival (P = 0.73) or overall survival (P = 0.68) between the two groups in univariate analysis. Receipt of AC was not a significant independent factor for survival, and completion of planned AC was a significant independent factor for recurrence-free survival and overall survival in multivariate analysis. CONCLUSIONS: The benefit of pancreatectomy for PDAC was the same between young and elderly patients. Completion of planned AC was important, and lowered-dose AC using S1 for elderly patients might be safe and therapeutically useful.

Safety of laparoscopic distal gastrectomy for gastric cancer when performed by trainee surgeons with little experience in performing open gastrectomy.

PURPOSE: This study aimed to evaluate the surgical outcomes and clinical safety of laparoscopic distal gastrectomy (LDG) when performed by trainee surgeons with little prior experience in performing open gastrectomy, under the guidance of trainer surgeons. METHODS: From January 2008 until March 2015, 17 trainee surgeons and 5 trainer surgeons performed LDGs to treat 371 patients with clinical stage T1-T3 gastric cancer. Of these patients, 140 and 231 underwent LDG performed by trainee surgeons and trainer surgeons, respectively. We retrospectively analyzed the surgical outcomes of the two groups. RESULTS: Trainee surgeons required significantly longer operation times than the trainer surgeons, with respective mean operation times of 262 and 223 min (p < 0.001). However, the mean blood loss volumes, average numbers of retrieved lymph nodes, postoperative complications, and postoperative hospital stay lengths did not differ significantly between LDGs performed by trainee surgeons and trainer surgeons. CONCLUSIONS: The study findings suggest that, under the guidance of trainer surgeons, trainee surgeons with little experience with open gastrectomy and even without prior experience with LDG can perform radical surgeries safely.

The validity of the surgical indication for intraductal papillary mucinous neoplasm of the pancreas advocated by the 2017 revised International Association of Pancreatology consensus guidelines.

PURPOSE: This study was performed to evaluate the surgical indication for intraductal papillary mucinous neoplasm (IPMN) advocated by the 2017 revised International Association of Pancreatology consensus guidelines (IAPCG2017). METHODS: The medical records of 63 patients who underwent pancreatectomy for IPMN were retrospectively reviewed. RESULTS: Thirteen patients had main-duct IPMN, 25 had mixed IPMN, and 25 had branch-duct IPMN with frequencies of high-grade dysplasia or invasive carcinoma of 62, 24, and 28%, respectively. The sensitivity and specificity of high-risk stigmata for high-grade dysplasia or invasive carcinoma advocated by the IAPCG2017 were 90 and 67%, respectively. Of 17 patients with invasive carcinoma, all patients had high-risk stigmata, and 16 had an enhanced mural nodule (MN) of ≥ 5 mm. The sensitivity and specificity of a ≥ 5-mm enhanced MN for predicting invasive carcinoma were 94% and 87%, respectively. CONCLUSIONS: Introducing a size threshold for enhanced MNs into the assessment of high-risk stigmata increases the specificity without jeopardizing the sensitivity. The surgical indication for any type of IPMN may be determined using only a ≥ 5-mm enhanced MN. When the type of IPMN is classified strictly, about half of IPMNs are mixed type, and most are benign. The surgical indication for mixed IPMN should be reconsidered.

Neutrophil-to-lymphocyte ratio and mural nodule height as predictive factors for malignant intraductal papillary mucinous neoplasms.

BACKGROUND: Accurate preoperative prediction for malignant IPMN is still challenging. The aim of this study was to investigate the validity of neutrophil-to-lymphocyte ratio (NLR) and mural nodule height (MNH) for predicting malignant intraductal papillary mucinous neoplasm (IPMN). METHODS: The medical records of 60 patients who underwent pancreatectomy for IPMN were retrospectively reviewed. RESULTS: NLR tended to be higher in malignant IPMN (median: 2.23) than in benign IPMN (median: 2.04; p = .14). MNH was significantly greater in malignant IPMN (median: 16 mm) than in benign IPMN (median: 8 mm; p < .01). The optimal cutoff values for the NLR and MNH were 3.60 and 11 mm, respectively. The sensitivity and specificity of NLR ≥3.60 for predicting malignant IPMN were 40% and 93%, and those of MNH ≥11 mm were 73% and 77%, respectively. Univariate analysis revealed that NLR ≥3.60 (p < .01) and MNH ≥11 mm (p < .01) were significant predictive factors. On multivariate analysis, enhanced solid component was identified as an independent factor, but NLR ≥3.60 and MNH ≥11 mm were not. CONCLUSIONS: NLR and MNH are suboptimal tests in predicting malignant IPMN; however, they can be useful to assist in clinical decision-making.

Effect of postoperative major complications on prognosis after pancreatectomy for pancreatic cancer: a retrospective review.

PURPOSE: To investigate the impact of postoperative complications on survival after curative resection for pancreatic cancer. METHODS: We reviewed retrospectively the medical records of 122 patients who underwent curative R0 resection for pancreatic cancer. Major complications included pancreatic fistula and hemorrhage of grade B or C according to the International Study Group of Pancreatic Fistula or Surgery criteria, and other complications of grade ≥III according to the Clavien-Dindo classification. RESULTS: Thirty-eight patients (31 %) suffered major postoperative complications and 40 patients (33 %) suffered minor complications only. Univariate survival analysis showed that patients with major complications had a significantly worse prognosis than those without major complications, with regard to recurrence-free survival (RFS) (P < 0.01) and overall survival (OS) (P < 0.01), whereas minor complications did not affect survival. Major complications significantly inhibited or delayed adjuvant chemotherapy. Multivariate survival analysis showed that the absence of postoperative major complications was an independent favorable factor for RFS (hazard ratio 0.48; 95 % confidence interval: 0.28-0.85) and OS (hazard ratio 0.47; 95 % confidence interval 0.27-0.81). CONCLUSIONS: Postoperative major complications after pancreatectomy for pancreatic cancer affect the prognosis.

Validity of the management strategy for intraductal papillary mucinous neoplasm advocated by the international consensus guidelines 2012: a retrospective review.

PURPOSE: The aim of this study was to investigate the validity of the management strategy for intraductal papillary mucinous neoplasms (IPMNs) advocated by the international consensus guidelines 2012 (ICG2012). METHODS: The medical records of 49 patients who underwent pancreatectomy for IPMN were retrospectively reviewed. RESULTS: According to preoperative imaging, 10 patients (20 %) had main-duct IPMNs, 20 (41 %) had mixed IPMNs, and 19 (39 %) had branch-duct IPMNs, with malignancy frequencies of 80, 15, and 37 %, respectively. Twenty-seven patients had high-risk stigmata and 21 had worrisome features, with malignancy frequencies of 59 and 10 %, respectively. The sensitivity, specificity, and positive and negative predictive values of high-risk stigmata for malignancy were 88, 65, 59, and 91 %, respectively. Lesions were malignant in 88 % of patients with an enhanced solid component, which was significantly correlated with the prevalence of malignancy (P < 0.01). However, of the 10 patients who underwent pancreatectomy solely due to a main pancreatic dilation of ≥10 mm, 9 (90 %) had benign IPMNs. CONCLUSIONS: Many mixed IPMNs defined according to ICG2012 are benign. Although the management strategy advocated by ICG2012 has been improved relative to the Sendai criteria, the different high-risk stigmata carry unequal weights. Consequently, ICG2012 remains suboptimal for predicting malignant IPMN.

Conversion surgery for initially unresectable locally advanced pancreatic ductal adenocarcinoma after chemotherapy followed by carbon-ion radiotherapy: a case report.

BACKGROUND: Recent advances in chemotherapy and chemoradiotherapy have enabled conversion surgery (CS) to be performed for selected patients with initially unresectable locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC). Many studies indicate CS might extend the survival of patients with initially unresectable LA PDAC. However, several clinical questions concerning CS remain, such as the optimal preoperative treatment. Carbon-ion radiotherapy (CIRT) is a unique radiotherapy that offers higher biological effectiveness than conventional radiotherapy. Here, we report a long-term survival case with initially unresectable LA PDAC who underwent CS after chemotherapy followed by CIRT. CASE PRESENTATION: The patient was a 72-year-old Japanese woman with unresectable LA pancreatic head cancer with tumor contact to the superior mesenteric artery (SMA). She underwent four courses of chemotherapy (gemcitabine plus nanoparticle albumin-bound paclitaxel). However, the lesion did not shrink and tumor contact with the SMA did not improve after chemotherapy. Because the probability of achieving curative resection was judged to be low, she underwent radical dose CIRT, and chemotherapy was continued. She complained of vomiting 2 months after CIRT. Although imaging studies showed no tumor growth or metastasis, a duodenal obstruction which was speculated to be an adverse effect of CIRT was observed. She could not eat solid food and a trans-nasal feeding tube was inserted. Therapeutic intervention was required to enable enteral nutrition. We proposed several treatment options. She chose resection with the expectation of an anti-tumor effect of chemotherapy and CIRT rather than course observation with tube feeding or bypass surgery. Therefore, subtotal-stomach-preserving pancreatoduodenectomy with portal vein resection was performed as CS. Pathological examination of the resected specimen revealed an R0 resection with a histological response of Evans grade IIA. Postoperatively, she recovered uneventfully. Adjuvant chemotherapy with tegafur/gimeracil/oteracil (S1) was administrated. At the time of this report, 5 years have passed since the initial consultation and she has experienced no tumor recurrence. CONCLUSIONS: The present case suggests that multidisciplinary treatment consisting of a combination of recent chemotherapy and CIRT may be beneficial for unresectable LA PDAC. However, further studies are required to assess the true efficacy of this treatment strategy.

Transvaginal resection of a gastrointestinal stromal tumor of the rectum: a case report.

BACKGROUND: The most common curative treatment for gastrointestinal stromal tumors (GISTs) is local excision. For rectal GISTs, however, local excision is difficult because of the anatomical features of the rectum. The optimal surgical approach is still under debate, and less invasive methods are desired. We herein report a case of transvaginal resection of a rectal GIST in a young woman. CASE PRESENTATION: A 21-year-old woman was diagnosed with a resectable GIST in the anterior rectal wall and underwent transvaginal tumor resection. The posterior vaginal wall was incised, revealing the tumor fully covered by the rectal mucosa. The rectal adventitia and muscular layer were incised, and the tumor was resected en bloc without rupture. The postoperative course was favorable, and the patient was discharged on postoperative day 12. No findings consistent with recurrence were present 6 months postoperatively. CONCLUSION: Transvaginal tumor resection is a treatment option as a minimally invasive procedure for GISTs in the anterior rectal wall in female patients.

Prognostic significance of lymph node metastasis in pancreatic tail cancer: A multicenter retrospective study.

Background: Distal pancreatectomy (DP) with lymph node (LN) dissection is the standard procedure for pancreatic ductal adenocarcinoma of the tail (Pt-PDAC). However, the optimal surgery including extent of LN dissection is still being debated. The present study investigated the incidence and prognostic impact of LN metastasis on patients suffering from Pt-PDAC. Patients and method: This multicenter, retrospective study involved 163 patients who underwent DP for resectable Pt-PDAC at 12 institutions between 2013 and 2017. The frequency of LN metastasis and the effect of LN dissection on Pt-PDAC prognosis were investigated. Results: There were high incidences of metastases to the LNs along the splenic artery in the patients with Pt-PDAC (39%). The rate of metastases in the LNs along the common hepatic, left gastric, and celiac arteries were low, and the therapeutic index for these LNs was zero. In pancreatic tail cancer located more distally, there were no metastases to the LNs along the common hepatic artery. Multivariate analysis revealed that tumor size was the only independent factor related to recurrence-free survival (HR = 2.01, 95% CI = 1.33-3.05, p = 0.001). The level of pancreas division and LN dissection along the common hepatic artery did not affect the site of tumor recurrence or recurrence-free survival. Conclusions: LN dissection along the hepatic artery for Pt-PDAC has little significance. Distal pancreatic transection may be acceptable in terms of oncological safety, but further examination of short-term outcomes and preservation of pancreatic function is required.

Mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater: a case report.

BACKGROUND: Mixed neuroendocrine-non-neuroendocrine neoplasms of the ampulla of Vater are rare and heterogenous, making it difficult to achieve a definitive preoperative diagnosis. Herein, we describe a patient in whom a provisional diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater was made preoperatively. CASE PRESENTATION: Computed tomography revealed an enhancing periampullary tumor in a 69-year-old man with obstructive jaundice. Subsequent duodenoscopy revealed an ulcerated lesion in the swollen ampulla of Vater, from which six biopsies were collected. Pathological examination revealed adenocarcinoma in five of them. The remaining one was a neuroendocrine neoplasm according to immunohistochemical analysis. With a provisional diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater, the patient underwent subtotal stomach-preserving pancreaticoduodenectomy with modified Child's reconstruction and was discharged without complications. Pathological examination revealed both adenocarcinoma and neuroendocrine carcinomas, each accounting for ≥ 30% of the tumor, resulting in a definitive diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater. Lymph node metastases with neuroendocrine components were also observed. Adjuvant chemotherapy was not administered because of the patient's renal dysfunction. Liver and lymph node metastases were detected 2 months after surgery, the neuroendocrine component being considered responsible for that relapse. The patient underwent platinum-based chemotherapy at 50% dosage, which initially resulted in significant tumor shrinkage; however, he died 6 months after surgery. CONCLUSIONS: While these tumors' heterogeneity make definitive preoperative diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater difficult, the possibility of this disease can be considered by careful examination. Further study is needed to establish the optimal diagnostic criteria and treatment strategy.

Preoperative frailty as a predictive factor for postoperative complications in patients with pancreatic cancer.

Frailty is considered one of the most important indicators of a patient's general condition. However, only a few studies have investigated the association between preoperative frailty and postoperative complications in pancreatic cancer. Therefore, this study aimed to examine this association in patients with pancreatic cancer. We retrospectively reviewed 52 consecutive patients who underwent pancreatectomy for pancreatic cancer between July 2019 and March 2021. Patients were classified into two groups according to the presence of postoperative complications. Their characteristics and clinical parameters, including physical function, were analyzed. Patients with postoperative complications had a higher prevalence of frailty (58.8% vs 14.3%, p = 0.003) and a shorter 6-min walk distance (380 m vs 436 m, p = 0.020) than those without postoperative complications. Logistic regression analysis identified preoperative frailty as the only independent risk factor for complications after pancreatectomy (p = 0.002). Preoperative frailty is associated with postoperative complications of pancreatectomy. Since preoperative frailty can be easily evaluated, it is a useful predictor of postoperative complications after pancreatectomy.

Anaplastic lymphoma kinase-positive inflammatory myofibroblastic tumor of the breast: a case report and review of the literature.

BACKGROUND: Few reports of inflammatory myofibroblastic tumor (IMT) of the breast have been published worldwide. Furthermore, primary anaplastic lymphoma kinase (ALK)-positive IMT of the breast is extremely rare. To date, only six patients with ALK-positive IMT have been reported in the literature. CASE PRESENTATION: A 52-year-old woman underwent a medical examination, and a left breast mass was detected. She did not feel a mass in her chest. Mammography showed a focal asymmetric density at the lower outer portion of the left breast. Breast ultrasonography showed a 1.2-cm hypoechoic lesion with relatively clear boundaries and poor blood flow. Magnetic resonance imaging and computed tomography revealed a solitary heterogeneous mass in the left breast. Pathologic examination revealed a fibrosing lesion with proliferation of fibroblastic cells arranged in a storiform pattern and admixed inflammatory cells. Immunohistochemical examination showed that the tumor cells were positive for ALK. Under the preoperative diagnosis of IMT, we performed partial mastectomy with adequate margins. The postoperative diagnosis was pathologically confirmed as IMT. Immunohistochemical staining also showed overexpression of ALK-1 in the tumor. The patient had a good clinical course for 24 months postoperatively, without recurrence or metastasis. CONCLUSIONS: IMT of the breast shows nonspecific imaging findings, making preoperative diagnosis difficult. Nevertheless, IMT has the characteristics of low-grade neoplasms with recurrence, invasion, and metastatic potential. Our report emphasizes the importance of determining a treatment plan as soon as possible based on an accurate diagnosis to improve the prognosis of this disease.

Machine learning-based model for prediction and feature analysis of recurrence in pancreatic neuroendocrine tumors G1/G2.

BACKGROUND: Pancreatic neuroendocrine neoplasms (PanNENs) are a heterogeneous group of tumors. Although the prognosis of resected PanNENs is generally considered to be good, a relatively high recurrence rate has been reported. Given the scarcity of large-scale reports about PanNEN recurrence due to their rarity, we aimed to identify the predictors for recurrence in patients with resected PanNENs to improve prognosis. METHODS: We established a multicenter database of 573 patients with PanNENs, who underwent resection between January 1987 and July 2020 at 22 Japanese centers, mainly in the Kyushu region. We evaluated the clinical characteristics of 371 patients with localized non-functioning pancreatic neuroendocrine tumors (G1/G2). We also constructed a machine learning-based prediction model to analyze the important features to determine recurrence. RESULTS: Fifty-two patients experienced recurrence (14.0%) during the follow-up period, with the median time of recurrence being 33.7 months. The random survival forest (RSF) model showed better predictive performance than the Cox proportional hazards regression model in terms of the Harrell's C-index (0.841 vs. 0.820). The Ki-67 index, residual tumor, WHO grade, tumor size, and lymph node metastasis were the top five predictors in the RSF model; tumor size above 20 mm was the watershed with increased recurrence probability, whereas the 5-year disease-free survival rate decreased linearly as the Ki-67 index increased. CONCLUSIONS: Our study revealed the characteristics of resected PanNENs in real-world clinical practice. Machine learning techniques can be powerful analytical tools that provide new insights into the relationship between the Ki-67 index or tumor size and recurrence.

Predictive factors for early recurrence after pancreaticoduodenectomy in patients with resectable pancreatic head cancer: A multicenter retrospective study.

BACKGROUND: Patients diagnosed with resectable pancreatic ductal adenocarcinoma often experience early recurrence even after upfront R0 resection. This study aimed to define early recurrence and identify preoperative risk factors for early recurrence after upfront pancreaticoduodenectomy in patients with resectable pancreatic ductal adenocarcinoma of the pancreatic head. METHODS: This multicenter, retrospective study involved 500 patients who underwent pancreaticoduodenectomy resectable pancreatic ductal adenocarcinoma of the pancreatic head at 10 institutions between 2007 and 2016. Preoperative, intraoperative, and postoperative clinicopathological results were compared between early and non-early recurrence groups. Predictors of early recurrence were determined using statistical analyses. RESULTS: Log-rank tests revealed a significant difference (P < .001) between recurrence within 3 to 6 months and 6 to 9 months. Early recurrence was subsequently defined as recurrence within 6 months. Patients were categorized into early recurrence (n = 104) and non-early recurrence groups (n = 389). The median overall survival of the early and non-early recurrence groups was 8.6 months and 42.6 months (P < .001), respectively. Preoperatively, high carbohydrate antigen 19-9 levels ≥120 U/mL, retroperitoneal invasion, and diabetes mellitus were identified as independent predictive risk factors for early recurrence according to multivariate analysis. Comparing survival rates among patients with 3, 2, 1, or none of these factors, the median overall survival was 17.6 (n = 90), 21.2 (n = 184), 47 (n = 141), and 61.5 (n = 73) months, respectively. CONCLUSION: The optimal period that defines the early recurrence for resectable pancreatic ductal adenocarcinoma of the pancreatic head is 6 months. Tumor size ≥20 mm, preoperative carbohydrate antigen 19-9 levels ≥120 U/mL, retroperitoneal invasion of the tumor, and the presence of diabetes mellitus are independently associated with early recurrence.