Curative resection via right hemicolectomy and regional lymph node dissection for colonic adenomatous polyposis of unknown etiology with adenocarcinomas localized in the right side of the colon: a case report

BACKGROUND

APC and MUTYH are both well-known colorectal polyposis causative genes. However, 30-50% of colorectal adenomatous polyposis cases are classified as colonic adenomatous polyposis of unknown etiology and lack identifiable pathogenic variants. Although guidelines recommend total proctocolectomy for colonic adenomatous polyposis of unknown etiology with over 100 adenomas, evidence is lacking. This study presents a unique case of localized colonic adenomatous polyposis of unknown etiology with multiple adenocarcinomas, treated with hemicolectomy and regional lymph node dissection.

CASE PRESENTATION

The patient was a 72-year-old woman whose colonoscopy revealed numerous polyps and two adenocarcinomas localized in the right side of the colon, with no lesions in the left side. The patient had no family history of polyposis or colorectal cancer. No extracolonic lesions, enlarged lymph nodes, or distant metastases were found. Considering the patient's age and lesion localization, laparoscopic right hemicolectomy with regional lymph node dissection was performed. Histopathological diagnosis revealed three adenocarcinoma lesions with no lymph node metastasis. The most advanced pathological stage was T2N0M0 Stage I (UICC 8th edition). The patient was alive 5 years postoperatively, without recurrence of cancer or polyposis in the remaining colon and rectum. To diagnose hereditary colorectal cancer/polyposis, a germline multigene panel testing for APC, EPCAM, MBD4, MLH1, MLH3, MSH2, MSH3, MSH6, MUTYH, NTHL1, PMS2, POLD1, POLE, and TP53 was performed using DNA extracted from blood samples: however, no pathogenic variant was detected. Therefore, the patient was diagnosed with colonic adenomatous polyposis of unknown etiology.

CONCLUSIONS

In this rare case, colonic adenomatous polyposis of unknown etiology, with numerous adenomatous polyps and multiple adenocarcinomas localized in the right side of the colon, was successfully treated with right hemicolectomy and regional lymph node dissection. Despite genetic analysis, no causative germline variants were identified. Segmental colectomy according to the distribution of polyps might be a curative approach.

[A Case of Adenocarcinoma of Pancreatic Head of Liver Disfunction after Pancreaticoduodenectomy with Celiac Artery Stenosis Treated by Urgent Median Arcuate Ligament Release]

This patient visited our hospital for the purpose of detailed examination of prostate cancer in his seventies. Abdominal contrast-enhanced computed tomography(CT)revealed a low-density mass of 2 cm in the pancreatic head. He was diagnosed with pancreatic cancer. Pancreaticoduodenectomy was performed after 2 courses of gemcitabine and S-1 therapy were performed as neoadjuvant chemotherapy. An intraoperative clamp test of the gastroduodenal artery showed that the pulsation of the common hepatic artery and the proper hepatic artery was weak but sufficient, so the gastroduodenal artery was cut and the operation was completed as planned. A blood test on the 1st day after the operation showed elevated levels of AST 537 U/L, ALT 616 U/L, and 7 hours later blood sampling showed further increases in AST 1,455 U/L, ALT 1,314 U/L. After a detailed review of the preoperative CT, celiac artery stenosis due to compression of the arcuate ligament was suspected, and urgent median arcuate ligament release was performed on the same day. Dissection of the arcuate ligament significantly improved the pulsation of the common hepatic artery and proper hepatic artery. Postoperatively, hepatic enzymes improved and ISGPS showed Grade B pancreatic juice leakage, but the patient was discharged from the hospital on the 49th postoperative day without any other complications. He took S-1 as adjuvant chemotherapy, and no signs of recurrence have been observed 9 months after the operation.

[A Case of Strangulated Bowel Obstruction after a Laparoscopic Hartmann's Operation for Rectal Cancer]

A 98-year-old woman presented with hematochezia and a circumferential type 2 tumor in the rectum Rb identified on fiberoscopy. We a performed laparoscopic Hartmann's operation and D2 lymphadenectomy for advanced rectal cancer. A sigmoid colostomy was created via the intraperitoneal route. On the postoperative day 12, the patient experienced abdominal pain. Computed tomography showed that the small intestine formed a closed loop in the pelvic space. The patient was diagnosed with a strangulated bowel obstruction of the small intestine for which an emergency exploratory laparotomy was performed. The small intestine, which had passed through a defect between the lifted sigmoid colon and the left abdominal wall, was strangulated by the lifted sigmoid colon. We performed partial resection of the small intestine. The patient died on postoperative day 32 of acute deterioration of aortic valve stenosis. There have been few reports of strangulated bowel obstruction resulting from internal hernia associated with colostomy. These findings demonstrate that it is important to select the appropriate route for colostomy creation in each case.

[Investigation of the Short-Term Outcome of Perioperative Heparinization in Laparoscopic Surgery for Colorectal Cancer]

In aging society, the number of colorectal cancer patients who take antithrombotic drugs is increasing. However, there are not established guidelines for perioperative management for antithrombotic drugs in laparoscopic surgery. Here, we investigated the clinical outcomes of antithrombotic drugs withdrawal and perioperative heparinization in laparoscopic surgery for colorectal cancer patients taking antithrombotic drugs. From January 2015 to December 2017 in our center, patients who took antithrombotic drugs and underwent laparoscopic surgery for colorectal cancer were reviewed retrospectively. The association between postoperative complications and heparinizations was analyzed. Among 79 patients taking antithrombotic drugs, heparinization was performed in 40 patients(50.6%). The total length of hospital stay in heparinization group was 21 days and significantly longer than 13 days in the non-heparinization group. There were no significant differences in the operation time, intraoperative blood loss, and postoperative complications between the 2 groups. The antithrombotic drugs withdrawal and perioperative heparinization were suggested to be safe and feasible in laparoscopic surgery for patients with colorectal cancer.

[A Case of Retroperitoneal Leiomyosarcoma Resected Radically by Pancreaticoduodenectomy with Vascular Resection]

A 54-year-old woman visited to a doctor nearby medical clinic complaining of loss of appetite. She was diagnosed with right hydronephrosis on abdominal ultrasonography, and referred to our hospital for further examination. Contrast abdominal computed tomography(CT)revealed that a 6.2 cm tumor with a contrast-enhancing effect inside in the retroperitoneum near the lower pole of the right kidney. She was diagnosed with hydronephrosis due to infiltration of the right kidney of a retroperitoneal tumor. The tumor was suspected of invading the duodenum and inferior vena cava, but no obvious lymph node or distant metastasis was observed. Abdominal MRI revealed a tumor showed hyperintensity on T2-weighted and diffusion-weighted images. We performed pancreaticoduodenectomy with inferior vena cava resection and right nephrectomy. The pathological diagnosis was leiomyosarcoma originating from retroperitoneum and pT2, pN0, pM0, pStage ⅢA. The postoperative course was good, and she was discharged 10 days after the operation. Thoracoabdominal CT showed a tumor 4 cm at the hepatic hilum three months after surgery, and EOB-MRI showed many tumors other than the same site, so multiple liver metastases were diagnosed as recurrence. Doxorubicin has been started and is still being treated.

[A Case of Liver Metastasis Complete Resection for Concurrent Overlapping Cancer of the Transverse Colon and Renal Cell Carcinomas that were Difficult to Differentiate from Hepatocellular Carcinoma]

A 79-year-old man visited the hospital because of constipation. Colonoscopy showed a transverse colon carcinoma. Dynamic CT showed a renal neoplastic lesion and 2 lesions in the liver with early staining and late wash out, and the liver lesions showed ring enhancement on EOB-MRI. The preoperative diagnosis was either transverse colon cancer, renal cell carcinoma, hepatocellular carcinoma, or metastatic liver cancer. The patient underwent partial transverse colon resection, partial right nephrectomy, and partial hepatic resection. Additional to the 2 liver lesions in S6, an intraoperative ultrasound showed 1 tumor in S5; therefore, 3 partial hepatectomies were performed. Histopathological findings revealed that the tumors in S5 and S6 were liver metastases of transverse colon cancer and renal cell carcinoma, respectively. The final diagnosis was transverse colon cancer, pT4a, pN0, pM1, pStage Ⅳa and papillary renal cell carcinoma, pT1a, pN0, pM1, pStage Ⅳ. For 9 months postoperatively, there was no apparent recurrence.

Pre‐emptive oral clarithromycin to reduce the skin toxicity of panitumumab treatment for metastatic colorectal cancer

79

Background: Chemotherapy with panitumumab is expected to be well tolerated and improve survival in patients with metastatic colorectal cancer (mCRC). However, skin toxicities are its most common adverse events. The aim of this trial was to evaluate the efficacy and safety of pre-emptive antibiotic treatment with clarithromycin (CAM) to prevent panitumumab skin toxicities. Methods: We conducted a phase lll, multicenter, open-label, randomized clinical trial on mCRC patients treated with pani- tumumab. Eligible patients were randomly assigned 1:1 to pre-emptive antibiotic and control groups. In the pre-emptive group, CAM administration (200 mg twice per day) continued daily through the panitumumab treatment period. The control regimen consisted of skin care only. The primary end point was the incidence of grade ≥ 2 skin toxicities during the 6-week skin treatment period. Results: Of 156 enrolled patients, 78 received pre-emptive antibiotic treatment, and 78 received reactive treatment. The number and incidence of grade ≥ 2 skin toxicities during the 6-week skin treatment period were 16 (21.3%) and 41 (54.7%) for the pre-emptive and control groups, respectively (HR, 0.32; 95% CI, 0.17–0.56). There was almost no difference in the rate of other adverse events between the two groups, but the incidence of grade ≥ 3 diarrhea in the pre-emptive group was high, at 8% vs. 1.3% in the control group. There were no treatment-related deaths. Conclusions: Prophylactic oral CAM together with relatively simple skin care was found to be effective in suppressing the development of grade ≥ 2 skin toxicities induced by panitumumab. Clinical trial information: UMIN000011485.

Intra-abdominal desmoid-type fibromatosis successfully resected using laparoscopic fluorescence imaging with indocyanine green after intersphincteric resection for rectal cancer

Successful resection of intra-abdominal tumors using indocyanine green (ICG) fluorescence imaging has not been reported. Here, we report a rare case of an intra-abdominal desmoid-type fibromatosis successfully resected using this technique after intersphincteric resection (ISR) for rectal cancer. One year after ISR for rectal cancer in a 47-year-old man, computed tomography showed a 50-mm intra-abdominal tumor near the left common iliac vein. Surgical resection was performed. The tumor was located in the mesentery of the remnant rectum after ISR. ICG fluorescence imaging confirmed the blood supply to the mesentery of the distal remnant rectum after tumor excision. The anal canal was successfully preserved without creating a permanent colostomy. The tumor was safely resected with resection margins, diagnosed as desmoid-type fibromatosis. No tumor recurrence was observed 6 months post-resection. This was the first case report to demonstrate the utility of this technique for an intra-abdominal tumor resection.

[A Resected Case of Adeno-Squamous Carcinoma of Gallbladder with Liver Invasions]

A patient was 70-year-old female. Because unknown fever following operation of left knee in December 20XX-1, abdominal simple CT was performed, diagnosed as cholecystitis and liver abscesses. However, her unknown fever did not improve with antibiotics therapy. Abdominal enhanced CT and MRI revealed to gallbladder cancer with liver invasion and metastases. These lesions were relatively localized in liver S4a/S5 and gallbladder, hepatoduodenal mesentery. Because unknown fever was exhausting, cholecystectomy, S4a+S5 hepatectomy with extrahepatic bile duct resection and lymph node dissemination were performed in January 20XX+1. In these pathological findings, there were moderate to poorly differentiated adenocarcinoma with squamous cell differentiation in almost area of gallbladder, diagnosed as adeno-squamous carcinoma with liver invasion and metastasis(pT3a[SI][H-inf], int, INF-β, ly1, v3, pn1, pN1, pM1, pStage ⅣB). One months after operation, abdominal CT revealed multiple liver metastatic recurrences. She died 7 months after operation. Although gallbladder adeno-squamous carcinoma has a poor prognosis, these many cases had a tendency to local infiltration accompanied with tumor fever. If curative resection might be obtained and the symptoms might be improved, aggressive resection should be performed.

Pre-emptive oral clarithromycin reduces the skin toxicity of panitumumab treatment for metastatic colorectal cancer

PURPOSE

Chemotherapy with panitumumab is expected to be well tolerated and improve survival in patients with metastatic colorectal cancer (mCRC). However, skin toxicities are its most common adverse events. The aim of this trial was to evaluate the efficacy and safety of pre-emptive antibiotic treatment with clarithromycin (CAM) to prevent panitumumab skin toxicities.

METHODS

We conducted a phase lll, multicenter, open-label, randomized clinical trial on mCRC patients treated with panitumumab. Eligible patients were randomly assigned 1:1 to pre-emptive antibiotic and control groups. In the pre-emptive group, CAM administration (200 mg twice per day) continued daily through the panitumumab treatment period. The control regimen consisted of skin care only. The primary end point was the incidence of grade ≥ 2 skin toxicities during the 6-week skin treatment period.

RESULTS

Of 156 enrolled patients, 78 received pre-emptive antibiotic treatment, and 78 received reactive treatment. The number and incidence of grade ≥ 2 skin toxicities during the 6-week skin treatment period were 16 (21.3%) and 41 (54.7%) for the pre-emptive and control groups, respectively (HR, 0.32; 95% CI, 0.17-0.56). There was almost no difference in the rate of other adverse events between the two groups, but the incidence of grade ≥ 3 diarrhea in the pre-emptive group was high, at 8% vs. 1.3% in the control group. There were no treatment-related deaths.

CONCLUSION

Prophylactic oral CAM together with relatively simple skin care was found to be effective in suppressing the development of grade ≥ 2 skin toxicities induced by panitumumab.

CLINICAL TRIAL REGISTRATION

UMIN000011485 DATE OF REGISTRATION: Sep 1st, 2013.

[A Case of Mesh Infection Due to Transverse Colon Cancer]

A 69-year-old female underwent a mesh repair for an abdominal incisional hernia 4 years previously in our hospital. She visited local hospital for abdominal pain and fever. Abdominal CT showed a localizes abscess formation above the mesh, then she was taken to our hospital. We suspected mesh infection and performed emergent mesh removal. After the operation, we examined for her anemia. Her colonoscopy and CT findings pointed to transverse colon cancer. We performed right hemicolectomy, and final diagnosis was transverse colon cancer pT4aN0M0, pStage Ⅱb. She underwent adjuvant chemotherapy, and 9 months after surgery, no recurrence was found.

[Capecitabine and Oxaliplatin(CAPOX)plus Bevacizumab as Second-Line Chemotherapy for Metastatic Colorectal Cancer]

OBJECTIVE

To evaluate the efficacy and safety of CAPOX plus bevacizumab as second-line chemotherapy for metastatic colorectal cancer.

METHODS

In this multicenter phase Ⅱ study, the planned number of patients was 48, but owing to poor case accumulation, registration was discontinued for 20 patients. The primary endpoint was the response rate(RR). Secondary endpoints were progression-free survival(PFS), overall survival(OS), disease control rate(DCR), and safety.

RESULTS

First-line treatment was combined with irinotecan in 14 cases and bevacizumab in 12 cases. The median number of second- line treatment courses was 7, and the median treatment period was 203 days. The reason for discontinuation of treatment was disease progression in 13 cases, adverse events in 4 cases, and other reasons in 3 cases. The best response was PR in 5 cases, SD in 8 cases, and NE in 4 cases. The RR was 25%, and the DCR was 65%. The median PFS was 7.2 months, and the median OS was 18.6 months. Grade≥3 adverse events were neutropenia in 3 cases and diarrhea and peripheral neuropathy in 2 cases each. There were no treatment-related deaths.

CONCLUSION

CAPOX plus bevacizumab was a safe and effective second-line treatment option for metastatic colorectal cancer.

[Bilateral Multiple Liver Metastases after Pancreatoduodenectomy for a Duodenal Neuroendocrine Tumor-A Case Report]

The patient was a 79-year-old woman. In January 20XX, upper gastrointestinal endoscopy revealed a duodenal tumor with bleeding and ulceration. This tumor was diagnosed as a duodenal neuroendocrine tumor(NET)based on biopsy findings. In March 20XX, the patient underwent pancreatoduodenectomy with lymph node dissemination. Based on these pathological findings, the tumor was diagnosed as a duodenal NET(G2)with a lymph node metastasis(T2, N1, M0, Stage Ⅲ). Twenty months after the operation, abdominal CT revealed multiple liver metastases(S4, S7, and S8). After this recurrence, she underwent the subcutaneous somatostatin analogue injection therapy every 28 days, and transarterial chemoembolization( TACE)when these recurrent tumors showed remarkable regrowth, once a year, accounting for her age. She has maintained good disease control for 5 years.

[Resection of the Acinar Cell Carcinoma of the Pancreas with Lymph Node Recurrence along the Lesser Curvature of the Stomach-A Case Report]

A 78-year-old woman had undergone subtotal stomach-preserving pancreatoduodenectomy for acinar cell carcinoma (ACC)of the pancreatic head approximately 2 years before presentation, and the pathological diagnosis had been pT2pN0pM0, fStageⅠB(JPS 7th). Adjuvant chemotherapy was discontinued after 3 months because of side effects. Contrast- enhanced CT and PET-CT 2 years postoperatively revealed a tumor measuring 2 cm with a high concentration of FDG in the minor curvature of the stomach. During laparotomy, a 3 cm large lymph node was palpated in the minor curvature of the stomach, and a small lymph node was found adjacently. We diagnosed the patient with multiple lymph node recurrences and performed gastric lymph node dissection of the minor curvature. The pathological diagnosis was a single 2 cm large ACC lymph node metastasis. The patient did not consent to postoperative adjuvant chemotherapy and showed no recurrence for 1 year and 7 months postoperatively. Pancreatic ACC is a rare pancreatic tumor, and its clinicopathologic features are still largely unknown. In recent years, there have been reports of active resection or long-term survival with anti-cancer drug treatment even in recurrent cases, such as the present case. However, the indication and method of anti-cancer treatment are unclear and might need the accumulation of many more cases.

[A Case of Mature Teratoma in the Hepatoduodenal Ligament]

A 60's woman was admitted to our hospital because of palpitations that occurred with exertion. Coronary angiography computed tomography(CT)of suspected angina detected a tumor in the pancreatic head region. Abdominal CT showed a poorly enhanced 40×32 mm solid tumor in the hepatoduodenal ligament that contained a fatty component and calcification. During surgery, the tumor was located in the hepatoduodenal ligament, adhered to the pancreatic head, common hepatic artery, gastroduodenal artery, portal vein and common bile duct. However, the tumor was resected by preserving them. The tumor contained stratified squamous epithelium, a sebaceous gland, nerve, a pancreatic gland, and an adrenal gland. The histological diagnosis was a mature cystic teratoma. The patient showed no recurrence in 2 years and 10 months post-surgery. Mature teratomas in the hepatoduodenal ligament are extremely rare. Some reports showed that combined resection was performed when the tumor was in contact with the common bile duct, portal vein, and arteries. However, in our case, the tumor was removed relatively safely without combined resection.

Efficacy of Negative Pressure Wound Therapy Followed by Delayed Primary Closure for Abdominal Wounds in Patients with Lower Gastrointestinal Perforations: Multicenter Prospective Study

Objectives:

The efficacy of negative pressure wound therapy (NPWT) and its application to severely contaminated wounds sustained during surgery remain to be established. Here, we evaluated the efficacy of utilizing NPWT until delayed primary closure (DPC) by assessing the infection rates in patients with lower gastrointestinal perforations.

Methods:

This prospective multicenter cohort study included 56 patients that underwent abdominal surgery for lower gastrointestinal perforations in eight institutions, from February 2016 to May 2017. All patients received NPWT after surgery before attempting DPC. The extent of peritonitis was categorized according to Hinchey's classification. Patients in stages II-IV were included.

Results:

Five patients had surgical site infections (SSIs) during NPWT and did not receive a DPC (9%). Of the 51 patients that received DPCs, 44 had no infection (91%) and 7 developed SSIs after the DPC (13.7%). For stages II, III, and IV, the SSI rates were 0%, 22.6%, and 35.7%, respectively; the median (range) times to wound healing were 15 (10-36), 19 (11-99), and 19 (10-53) days, respectively. There were no significant differences between the stages.

Conclusions:

NPWT followed by DPC resulted in low infection rates in each peritonitis stage. This approach appears promising as an alternative to traditional DPC alone for treating lower gastrointestinal perforations.

Adjuvant Chemotherapy after Neoadjuvant Chemotherapy and Long-term Outcomes of CAPOX Plus Bevacizumab Followed by TME for High-risk Localized Rectal Cancer

Objectives:

We previously reported the feasibility of neoadjuvant capecitabine and oxaliplatin plus bevacizumab as a treatment for locally advanced rectal cancer (UMIN000003219). The aim of this study is to investigate the prognostic relevance of neoadjuvant chemotherapy followed by total mesorectal resection (TME).

Methods:

Twenty-five patients of our prior multicenter prospective study of neoadjuvant chemotherapy followed by TME enrolled to this study. We analyzed the adjuvant chemotherapy regimen, and the duration between surgery and initial chemotherapy treatment. Five-year progression-free survival and overall survival were estimated using the Kaplan-Meier method.

Results:

Among survivors, the median follow-up time was 66 months. Recurrence occurred in six patients, all of whom had suboptimal tumor regression after neoadjuvant chemotherapy. Five patients died from other causes. The rate of local recurrence and distant metastasis was 17.4% and 8.7%, respectively. Five-year progression-free survival was 70.0%, and 5 year overall survival was 84.0%.

Conclusions:

We report the long-term survival of patients who received neoadjuvant chemotherapy without radiation followed by TME, revealing a generally favorable prognosis.

Gradient subthalamic neurodegeneration and tau pathology in the hypoglossal nucleus as essential pathological markers of progressive supranuclear palsy - Richardson syndrome

Progressive supranuclear palsy - Richardson syndrome (PSP-RS) was first described in 1964 by Steele et al. Tau pathology has not been reported in the hypoglossal nuclei of PSP-RS patients, whereas Steele et al. described gliosis with no remarkable neuronal losses in the hypoglossal nucleus. This study aimed to investigate the distribution and degree of tau pathology-associated neurodegeneration, with an emphasis on the hypoglossal nucleus, in patients with PSP-RS. Six clinicopathologically proven PSP-RS cases were included in this study. All patients were clinicopathologically and immunohistochemically re-evaluated. This study confirmed the following neuropathological characteristics of PSP-RS: (1) neurodegeneration usually affects the striatonigral system and cerebellar dentate nucleus; (2) the cerebellar afferent system in PSP-RS is affected by absent-to-mild neurodegeneration; and (3) the extent of tau distribution throughout the central nervous system is greater than the extent of neurodegeneration. Furthermore, we found that subthalamic neurodegeneration was more prominent in the ventromedial region than in the dorsolateral region. Nevertheless, the tau pathology showed no remarkable differences between these two sites. Interestingly, the tau pathology was frequently observed in the hypoglossal nuclei of PSP-RS patients. Gradient neurodegeneration of the subthalamus and tau pathology in the hypoglossal nucleus could be regarded as essential pathological features of PSP-RS.

[A Case of Neuroendocrine Carcinoma Treated with Salvage Surgery after Systemic Chemotherapy]

A man in his 50s was admitted to our hospital due to hematemesis.Esophagogastroduodenoscopy revealed an 8 cm type 2 gastric tumor.The tumor was histologically diagnosed as a neuroendocrine carcinoma.CT showed that the tumor had directly infiltrated the liver but there was no distant metastasis.We performed open distal gastrectomy, D2 lymph node dissection, partial hepatectomy, and cholecystectomy.Four months after the surgery, metastases of the right adrenal gland and dorsal part of the inferior vena cava were found.Although a significant tumor reduction was obtained by 12 courses of chemotherapy with CDDP plus CPT-11, this effective treatment was discontinued for the patient's convenience.Fifteen months after the surgery, metastasis of the right adrenal gland and dorsal part of inferior vena cava demonstrated re-growth without any further metastasis.After 4 courses of the same regimen, a partial response was obtained for the recurrences.As a salvage surgery, we performed open right adrenal gland and the lymph nodes of dorsal of IVC resection.The patient is alive without recurrence 1 year after the salvage surgery.

[A Case of Long-Term Disease Control after Administration of Oxaliplatin for Esophagogastric Junction Squamous Cell Carcinoma]

There are few reports of using oxaliplatin(L-OHP)for esophageal squamous cell carcinoma.We report a case of long-term disease control after administration of L-OHP for esophagogastric junction squamous cell carcinoma(EG).A woman in her 40s was diagnosed with EG(cT3, cN2, cM0, cStage Ⅲ).She received thoracoscopic, laparoscopic-assisted, subtotal esophagectomy with 3-field dissection after 3 courses of preoperative chemotherapy with DCF(docetaxel hydrate, cisplatin, 5- fluorouracil).Reconstruction was achieved using a retrosternally shifted gastric tube and transesophageal gastro-tubing. Pathological examination showed EG(ypT3, ypN2, ypM0, ypStage Ⅲ)(chemotherapy evaluation: Grade 1a).After 12 months, para-aortic lymph node recurrence(#112aoP, #16a2lat)was observed on a follow-up CT examination.First, we administered 5 courses of chemotherapy with SOX(S-1 100mg/m2 day 1-14 and L-OHP 100 mg/m2 day 1).Recurrent lymph nodes shrunk slightly, and there were no new lesions.Subsequently, there was no other adverse event except for Grade 1 chemotherapy-induced neuropathy.Second, we administered 3 courses of chemotherapy with FOLFOX(5-FU 400mg/m2, L-OHP 85mg/m2, Leucovorin 200 mg/m2 day 1, 5-FU 1,600mg/m2/46 hr)in combination with radiotherapy(total 60 Gy/ 30 Fr).Recurrent lymph nodes shrunk slightly, and there were no new lesions.Subsequently, there was no other adverse event except for Grade 1 chemotherapy-induced neuropathy.No new recurrence was observed 19 months after the first recur- rence.The patient continues to receive weekly nab-PTX(85mg/m2).A regimen that includes L-OHP is useful in the treatment of advanced or recurrent esophageal squamous cell carcinoma.

P254 The differential impact of renal resistive index on future cardiovascular event in the hospitalised cardiovascular patients according to left ventricular ejection fraction: J-VAS study

Introduction

Renal resistive index (RRI) not only reflects renal vascular hemodynamics but also correlates well with systemic arterial stiffness. RRI associated with cardiovascular events in the selected group of cardiovascular patients including heart failure (HF). However, previous study limited only in the preserved ejection fraction (EF) patients.

Purpose

To determine the differential impact of RRI on cardiovascular events among cardiovascular patients according to EF.

Methods

A retrospective analysis of the Jichi Vascular Hemodynamics in Hospitalised Cardiovascular Patients (J-VAS) cohort. EF and RRI were measured in all patients, then categorised into groups of reduced EF (rEF < 40%), mid-range EF (mrEF 41-49%), and preserved EF (pEF≥50%). The latter group was subdivided into RRI≥0.8 and <0.8 to identify the risk of the primary endpoint, which was the composite of cardiac death, HF, acute coronary syndrome (ACS), aortic disease, arterial occlusion, and stroke.

Results

We included 1765 patients (mean age 64.7 years, 76% men). The most common diagnoses were ACS(66%) and HF(25%). During the median follow up of 1.9 years, 252 cardiovascular events occurred, 30.7%, 17.7%, and 10.4% in the rEF, mrEF and pEF group. RRI≥0.8 associated with the primary endpoint in the patients with pEF (Hazard ratio(HR), 1.69; 95%confident interval(CI) 1.11-2.58), but the association was not found in the other EF groups. Multivariate Cox regression analysis putting the pEF with RRI < 0.8 as a reference, pEF with RRI≥0.8 had a comparable risk for the primary endpoint to the mrEF group (HR, 1.55; 95%CI, 1.04-2.30 and HR, 1.92; 95%CI, 1.31-2.80, respectively), while the risk was highest in the rEF group (HR, 3.80; 95%CI, 2.73-5.29).

Conclusions

The risk of cardiovascular events in cardiovascular patients with pEF related to renal vascular hemodynamic alterations justified by RRI. In the patients with pEF, those with high RRI had comparable risk to the mrEF patients.

Risk of RRI≥0.8 for the primary endpoint Preserved EF HR (95%CI); P Mid-range EF HR (95%CI); P Reduced EF HR (95%CI); P Model 1 2.05 (1.39-3.02); P <0.001 1.60 (0.81-3.18); P =0.179 0.94 (0.53-1.67); P =0.838 Model 2 1.86 (1.25-2.78); P =0.002 1.33 (0.65-2.72); P =0.430 0.93 (0.52-1.66); P =0.792 Model 3 1.69 (1.11-2.58); P =0.015 1.10 (0.51-2.36); P =0.810 0.70 (0.38-1.28); P =0.242 Adjusted hazard ratio of RRI≥0.8 for the primary endpoint, RRI≥0.8 associated with a significant risk for the primary endpoint in the pEF group but not in the mrEF and rEF group. Model 1 was adjusted for age, sex and body mass index (BMI). Model 2 was adjusted for age, sex, BMI, smoking, dyslipidemia, and diabetes. Model 3 was adjusted for age, sex, BMI, smoking, dyslipidemia, diabetes, and glomerular filtration rate (GFR).

Abstract P254 Figure. Survival plot of the 4 subgroups

[A Case of Pancreatic Head Cancer after Esophagectomy and Gastrectomy Treated with Pancreatoduodenectomy]

A woman in her 40s was hospitalizedfor jaundice. Six years before, she hadbeen diagnosedwith synchronous esophageal andgastric cancers andhadund ergone subtotal esophagectomy andtotal gastrectomy, accompaniedby reconstruction with the pedicled jejunum. Multimodal imaging revealed a tumor at the pancreatic head, probably pancreatic cancer, which induced severe stenosis of the intrapancreatic bile duct. Scraping cytology findings of the lesion via the percutaneous transhepatic cholangial drainage(PTCD)route strengthenedthe suspicion. In the image, although no obvious invasion of the major vessels or apparent distant metastases were detected, an abnormal shadow was found continuously lining the main tumor andpara -aortic region, which was a contraindication for curative resection. Therefore, we performed neoadjuvant chemotherapy with gemcitabine plus S-1. After 3 courses, the lesion size reduced notably, and pancreatoduodenectomy was performed. The pathological diagnosis was pancreatic cancer(ph, ypT3, ypN1a, ypM0, ypStage ⅡB). Except for pancreatic fistulas(Clavien-Dindo Ⅲa), the postoperative clinical course was uneventful, andshe was dischargedon postoperative day 27. To date, the patient is alive without recurrence and is undergoing adjuvant chemotherapy with S-1.

[Two Cases of Intraductal Papillary Neoplasm of the Bile Duct(IPNB)Resected with Hepatectomy]

Case 1: A man in his 70s was referred to our hospital for further examination of a liver tumor(S3, 3 cm)detected by ultrasonography. Multimodal image examination showed a cystic lesion with solid papillary components located in the S4 accompanied by dilatation of the surrounding intrahepatic bile duct. Although biliary cytology did not indicate confirmed malignancy, the lesion was thought to be an intraductal papillary neoplasm of bile duct(IPNB)with malignant potential, and a left lobectomy was performed. Histopathological examination revealed a papillary tumor in the intrahepatic bile duct which consisted of atypical epithelial cells of pancreatobiliary type, and the lesion was diagnosed as an IPNB with high-grade intraepithelial neoplasia. Case 2: A woman in her 70s was referred to our hospital because of a liver tumor(S4, 8 cm)detected by ultrasonography. Multimodal image examination showed a cystic lesion localized to the liver(S3, 8 cm), and endoscopic retrograde cholangiopancreatography(ERCP)showed continuity of the cyst and the intrahepatic bile duct. The biliary cytology was positive, and the lesion was thought to be a malignant IPNB. After preoperative drainage of the cystic lesion, a left lobectomy was conducted. Histopathological examination showed that the papillary tumor localized to the bile duct and atypical epithelium cells of pancreatobiliary type were infiltrating into the surrounding matrix. We diagnosed this tumor as an IPNB with an associated invasive carcinoma.

[A Case of Lymph Node Recurrence with Invasion to the Trachea after the Resection of Esophageal Cancer Treated by Multidisciplinary Treatment]

A 78-year-old man who underwent esophagectomy for middle thoracic esophageal squamous cell carcinoma(pT1bN0M0, pStage Ⅰ)was diagnosed with lymph node recurrence 12 months after the initial surgery. He received chemoradiotherapy(5- fluorouracil plus cisplatin); however, the treatment was terminated at the middle of the treatment course because of progressive disease. He received chemotherapy(docetaxel plus 5-fluorouracil plus cisplatin)as a second-line treatment, which was also canceled due to serious adverse events. Partial response was achieved after the second therapy; therefore, surgical excision was performed. Thirteen months after the second surgery, he was diagnosed with second local recurrence with invasion to the trachea. Another course of chemotherapy(docetaxel[2-weekly]plus 5-fluorouracil plus cisplatin)was administered, which also achieved a partial response. Thus, surgical excision with partial tracheal resection and mediastinal tracheostomy was performed. He has been alive without recurrence for 6 months after the final operation. In case of postoperative solitary lymph node recurrence of esophageal cancer, long-term survival can be expected with multidisciplinary treatment.

Correlation between Skeletal Muscle Mass and Adverse Events of Neoadjuvant Chemotherapy in Patients with Gastric Cancer

PURPOSE

Neoadjuvant chemotherapy (NAC) followed by surgery is a promising treatment strategy for patients with advanced gastric cancer. Severe toxicity associated with the treatment may reduce the dose intensity of chemotherapy, resulting in the effect of chemotherapy being attenuated. Recently, skeletal muscle mass has been reported to be associated with the treatment outcomes of cancer patients. The purpose of this study was to clarify whether pretreatment skeletal muscle mass is a predictor of adverse events as well as the relationship between changes in skeletal muscle mass and adverse events during NAC.

METHODS

This study included 41 advanced gastric cancer patients who were treated with NAC followed by surgery. Body composition was assessed before and after NAC. The relationship between the pre-NAC body composition and adverse events was investigated as well as the relationship between changes in body composition and adverse events.

RESULTS

Univariate and multivariate analyses revealed that low pre-NAC skeletal muscle mass was the only factor significantly associated with severe diarrhea (p = 0.03). There was no significant difference in body weight before and after NAC, but skeletal muscle mass was significantly reduced after NAC (-5.93 ± 7.69%, p < 0.01). Furthermore, patients who experienced severe diarrhea showed significantly greater relative skeletal muscle decrease than those who did not (p = 0.03).

CONCLUSIONS

Pre-NAC low skeletal muscle mass was a useful predictor of severe diarrhea. Prevention of severe adverse events may contribute to maintaining the skeletal muscle mass.

Distinct Clinical Factors in Hospitalized Patients with Diverticular Bleeding and Diverticulitis

BACKGROUND/AIMS

It is unclear why colonic diverticular bleeding and diverticulitis rarely coexist. This study compared the characteristics of these conditions.

METHODS

This single-center retrospective study examined 310 consecutive patients hospitalized with an episode of diverticular disease (cases) and outpatients without a diverticular episode (controls) from January 2012 to December 2015. We investigated distinct clinical factors in hospitalized patients with diverticular bleeding and diverticulitis.

RESULTS

We identified 183 patients with 263 episodes of diverticular bleeding and 127 patients with 135 episodes of diverticulitis during the study period. Patients with diverticular bleeding were significantly older than those with diverticulitis (median age 76 vs. 56 years) and had more cardiovascular disease, hypertension, diabetes, cerebrovascular disease, chronic kidney disease, lipid disorder, or a poorer performance status. Significantly more diverticular bleeding patients were taking antiplatelet drugs, anticoagulant drugs, proton pump inhibitors, or laxative agents. Multivariate analysis revealed that an age > 65 years (OR 5.42), and antiplatelet agent use (OR 7.29) were more significant risk factors for diverticular bleeding than for diverticulitis.

CONCLUSIONS

Elderly people using antiplatelet drugs may be more susceptible to diverticular bleeding than diverticulitis.

Survival outcomes of appendiceal mucinous neoplasms by histological type and stage: Analysis of 266 cases in a multicenter collaborative retrospective clinical study

AIM

Appendiceal mucinous neoplasms are rare, and thus the literature is sparse with regard to histological types, staging, and prognosis. In particular, it is unclear how long-term outcome may differ between mucinous adenocarcinomas and other adenocarcinomas. In the present study, we aimed to investigate the histological types and stages of appendiceal neoplasms, and to evaluate the prognostic impacts of these factors in patients with mucinous adenocarcinomas and non-mucinous adenocarcinomas.

METHODS

Patients with appendiceal tumors diagnosed between 2007 and 2016 were retrospectively identified from the databases of 19 institutions in the Clinical Study Group of Osaka University, Colorectal Group.

RESULTS

A total of 266 patients with appendiceal tumors were identified, of whom 130 had pathologically diagnosed adenocarcinomas, including 57 with mucinous adenocarcinomas and 73 with non-mucinous adenocarcinomas. Five-year overall survival (OS) rates were 64.5% for mucinous adenocarcinomas, and 49.0% for non-mucinous adenocarcinomas. OS was significantly shorter among patients with non-mucinous adenocarcinomas compared to mucinous adenocarcinomas. Among patients with mucinous adenocarcinomas, 5-year OS rates were 53.6% for stage 0/I, 82.6% for II/III, and 48.4% for IV. Among patients with non-mucinous adenocarcinomas, 5-year OS rates were 90.9% for stage 0/I, 68.8% for II/III, and 7.1% for IV. Analysis of patients with stage IV disease revealed significantly shorter OS among patients with non-mucinous adenocarcinomas compared to mucinous adenocarcinomas.

CONCLUSION

Our present findings showed a better prognosis in patients with mucinous adenocarcinomas compared to non-mucinous adenocarcinomas. In this setting, Union for International Cancer Control staging was associated with prognosis for non-mucinous adenocarcinomas, but not for mucinous adenocarcinomas.

[A Case of Adenosquamous Carcinoma of Pancreas Treated with Conversion Surgery after Systemic Chemotherapy]

A man in his 60s reported upper abdominal pain; close examination revealed a tumor in the body-tail of the pancreas that was suspected to be infiltrating the stomach. Multiple liver lesions(S3, S4)were also detected. Histological examination by EUS-FNA showed poorly-differentiated carcinoma; thus, this case was diagnosed with unresectable pancreatic cancer with liver metastases(cT3, cN1[No. 7], cM1[P0, H1], cStage Ⅳ: JPS 7th). After 2 kinds of systemic chemotherapy(9 courses of GEM plus nab-PTX and 9 courses of modified FOLFIRINOX), obvious distant metastases or local progression did not appear and conversion surgery was scheduled. Although a metastatic lesion was identified at S5 of the liver just before the surgery, it was assumed that an R0 resection could be achieved; therefore, the operation(distal pancreatectomy with combined proximal gastrectomy, left adrenalectomy, lymph node dissection, partial hepatectomy of S5, and cholecystectomy)was performed. Histopathological examination showed squamous metaplasia of the epithelial tissue combined with glandular formation. This case was, thus, diagnosed as adenosquamous carcinoma of pancreas. This patient was discharged 90 days after the operation. The patient is still alive 2 years and 2 months since the first diagnosis.

mFOLFOX6 plus bevacizumab to treat liver-only metastases of colorectal cancer that are unsuitable for upfront resection (TRICC0808): a multicenter phase II trial comprising the final analysis for survival

BACKGROUND

The TRICC0808 trial is a phase II multi-institutional trial that investigated the efficacy of preoperative mFOLFOX6 + bevacizumab (BV) therapy for liver-only metastasis that is unsuitable for upfront resection. The R0 resection rate in the efficacy analysis has been reported to be 44.4%, and the final analysis for survival was conducted (data fixation on February 16, 2015).

METHODS

Six cycles of mFOLFOX6 + BV therapy were applied to patients with liver-only metastases, which were > 5 cm in diameter or more than four tumors (H2 and H3), and hepatectomy was performed if possible. Primary and secondary endpoints were the R0 hepatectomy rate and overall survival (OS), respectively.

RESULTS

Of 46 patients registered, OS was analyzed for 45 patients in whom the 3-year OS rate from the starting date of chemotherapy was 44.0% with a 33.6-month median survival time (MST). The 3-year OS rate of 31 patients with hepatectomy, including resection after an additional chemotherapy, was 61.3% with a 43.1-month MST, which was significantly better than 0% of the 3-year OS rate with a 21.0-month MST of 14 patients without hepatectomy (p value < 0.0001). In 24 patients who underwent hepatectomy after six cycles of protocol chemotherapy, the 3-year relapse-free survival rate was 8.3%, with a 36.8-month MST.

CONCLUSIONS

This final analysis of the TRICC0808 trial revealed a better long-term survival in patients with hepatectomy after mFOLFOX6 + BV therapy, although most examined patients eventually developed recurrence. Thus, hepatectomy after chemotherapy might improve the survival in patients with advanced liver metastases, although cure remains difficult.

Medication-related osteonecrosis of the jaw after tooth extraction in cancer patients: a multicenter retrospective study

Root amputation, immunosuppressive therapy, mandibular tooth extraction, pre-existing inflammation, and longer duration of treatment with bone-modifying agents were significantly associated with an increased risk of medication-related osteonecrosis of the jaw. Hopeless teeth should be extracted without drug holiday before the development of inflammation in cancer patients receiving high-dose bone-modifying agents.

INTRODUCTION

No studies have comprehensively analyzed the influence of pre-existing inflammation, surgical procedure-related factors such as primary wound closure, demographic factors, and drug holiday on the incidence of medication-related osteonecrosis of the jaw (MRONJ). The purpose of this study was to retrospectively investigate the relationships between these various factors and the development of MRONJ after tooth extraction in cancer patients receiving high-dose bone-modifying agents (BMAs) such as bisphosphonates or denosumab.

METHODS

Risk factors for MRONJ after tooth extraction were evaluated with univariate and multivariate analyses. The following parameters were investigated in all patients: demographics, type and duration of BMA use, whether BMA use was discontinued before tooth extraction (drug holiday), the duration of such discontinuation, the presence of pre-existing inflammation, and whether additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed.

RESULTS

We found that root amputation (OR = 22.62), immunosuppressive therapy (OR = 16.61), extraction of mandibular teeth (OR = 12.14), extraction of teeth with pre-existing inflammation, and longer duration (≥ 8 months) of high-dose BMA (OR = 7.85) were all significantly associated with MRONJ.

CONCLUSIONS

Tooth extraction should not necessarily be postponed in cancer patients receiving high-dose BMA. The effectiveness of a short-term drug holiday was not confirmed, as drug holidays had no significant impact on MRONJ incidence. Tooth extraction may be acceptable during high-dose BMA therapy until 8 months after initiation.

Efficacy of Negative-Pressure Wound Therapy for Preventing Surgical Site Infections after Surgery for Peritonitis Attributable to Lower-Gastrointestinal Perforation: A Single-Institution Experience

BACKGROUND AND PURPOSE

For patients at high risk, such as those with lower-gastrointestinal perforations, it is important to establish a preventive method that reduces the incidence of surgical site infections (SSIs) significantly. We applied negative-pressure wound therapy (NPWT) as part of a delayed primary closure approach to prevent SSIs. This study evaluated the value of this technique.

METHODS

We included prospectively 28 patients undergoing abdominal surgery for peritonitis caused by a lower-gastrointestinal perforation between May 2014 and November 2015. Historical controls comprised retrospective data on 19 patients who had undergone primary suturing for managing peritonitis incisions for a lower-gastrointestinal perforation from January to December 2013.

RESULTS

We found a significant association between the SSI incidence and the type of incision management (10.7% with NPWT and delayed closure vs. 63.2% with primary suturing; p < 0.001). There was no significant difference between the groups in the length of the hospital stay (22 days for NPWT and delayed closure vs. 27 days for primary suturing; p = 0.45). No severe adverse events were observed related to NPWT.

CONCLUSION

The use of NPWT and delayed primary closure was an effective measure for preventing SSI in patients undergoing abdominal surgery for peritonitis caused by lower-gastrointestinal perforation.

Skeletal Muscle Loss during Neoadjuvant Chemotherapy Is an Independent Risk Factor for Postoperative Infectious Complications in Patients with Advanced Esophageal Cancer

OBJECTIVE

Neoadjuvant therapy followed by surgery has been the standard treatment for advanced esophageal cancer. Severe toxicities may influence body composition, including skeletal muscle mass, and increase postoperative complications. The purpose of this study was to evaluate the influence of sarcopenia, changes in body composition, and adverse events during neoadjuvant chemotherapy (NACT) on postoperative complications in esophageal cancer patients.

METHODS

A total of 83 patients with esophageal cancer undergoing NACT followed by esophagectomy were included. Body composition was assessed before chemotherapy and before esophagectomy. The relationships between postoperative infectious complications and sarcopenia, changes in body composition, and adverse events during NACT were investigated.

RESULTS

Univariate analysis revealed that skeletal muscle loss during NACT, but not preoperative sarcopenia, was significantly higher in the complication (+) group. Febrile neutropenia tended to occur frequently in the complication (+) group. Multivariate analysis demonstrated that skeletal muscle loss was the only factor significantly associated with infectious complications (p = 0.029). Among adverse events, febrile neutropenia was significantly associated with a decrease in skeletal muscle mass.

CONCLUSION

Loss of skeletal muscle mass during NACT was a significant risk factor for postoperative infectious complications in patients with esophageal cancer. Prevention of severe adverse events may reduce postoperative infectious complications.

[Two Cases of Locally Recurrent Rectal Cancer Undergoing Preoperative Chemoradiationtherapy]

Case 1 is a 68-year-old woman with locally recurrent rectal cancer(LRRC)developed 5 years after resection of primary rectal cancer. The tumor seized right lateral side in pelvic. We performed tumor excision after preoperative chemoradiation comprised external beam radiation with oral S-1(tegafur/gimeracil/oteracil). He has been relapse-free for 3 years 3months after surgery. Case 2 is a 74-year-old man with LRRC developed 2 years after resection of primary rectal cancer. The tumor was located dorsal to anastomosis site in pelvic. We performed abdominoperineal resection for LRRC after preoperative chemoradiation with oral S-1. He has been relapse-free for 2 years. It was suggested that preoperative radiotherapy combined with oral FU for local recurrence after rectal cancer may contribute to distant and local control.

Changes regarding Age and Correlations between Serum Lipids and Body Mass Index in Humankind

Objectives: To improve insight into age and gender related distributions of serum lipids and their correlation with body mass index (BMI).

Methods: Serum lipids embracing atherogenic index (AI) and BMI were analyzed from the results obtained in 19,823 men and 14,788 women undergoing a health examination between 1986 and 1996.

Results: The changes in total cholesterol (TC), triglyceride (TG), AI and BMI differed regarding gender. Although high-density lipoprotein-cholesterol (HDL-C) showed a flat pattern for all ages in both genders, its level in women was higher than in men. The ratio of the number in the unsuitable range to those in the suitable range increased with age as to TC in both sexes, then more than half of the population have an unsuitable level in the sixth decade. As for the correlation between serum lipids and BMI: TC, TG and AI correlated positively, but HDL-C correlated negatively. There were significant gaps between both age and gender.

Conclusions: We suggest that the normal range of values of serum lipids needs to be revised according to gender and age to evaluate the risk status for a cardio-cerebrovascular disease more precisely in the field of preventive medicine. Simpler guidelines are preferable in specialized care as well as in general practice, particularly since computer technology is not yet universally adapted. In the near future, when computed information technology will be as common as the electricity and the telephone are current on the whole earth, all guidelines will have to be computed on the spot and personally.

[A Case of Diaphragmatic Metastasis from Adenocarcinoma of the Rectum Treated via Surgical Resection]

A 67-year-oldman underwent lower anterior resection for rectal cancer andresection of liver metastatic tumor 5 years later. Seven years and 2 months after the initial surgery, a soft tissue mass was detected in the left diaphragm. Further retrospective review of CT scan images showedthat the diaphragmatic tumor was present just before the hepatectomy. Partial resection of the left diaphragm was performed, and no relapse has occurred since then for 2 years. Most cases of diaphragmatic metastasis are considered to arise from dissemination, but we considered this case as more likely to be hematogenous. When surgery is chosen to treat metastatic tumors of colorectal cancer, checking for other metastasis via preoperative imaging andperforming curative resection is important.

A multicenter retrospective study of the risk factors associated with medication-related osteonecrosis of the jaw after tooth extraction in patients receiving oral bisphosphonate therapy: can primary wound closure and a drug holiday really prevent MRONJ?

Root amputation, extraction of a single tooth, bone loss or severe tooth mobility, and an unclosed wound were significantly associated with increased risk of developing medication-related osteonecrosis of the jaw (MRONJ). We recommend a minimally traumatic extraction technique, removal of any bone edges, and mucosal wound closure as standard procedures in patients receiving bisphosphonates.

INTRODUCTION

Osteonecrosis of the jaws can occur following tooth extraction in patients receiving bisphosphonate drugs. Various strategies for minimizing the risk of MRONJ have been advanced, but no studies have comprehensively analyzed the efficacy of factors such as primary wound closure, demographics, and drug holidays in reducing its incidence. The purpose of this study was to retrospectively investigate the relationships between these various risk factors after tooth extraction in patients receiving oral bisphosphonate therapy.

METHODS

Risk factors for MRONJ after tooth extraction were evaluated using univariate and multivariate analysis. All patients were investigated with regard to demographics; type and duration of oral bisphosphonate use; whether they underwent a discontinuation of oral bisphosphonates before tooth extraction (drug holiday), and the duration of such discontinuation; and whether any additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed.

RESULTS

We found that root amputation (OR = 6.64), extraction of a single tooth (OR = 3.70), bone loss or severe tooth mobility (OR = 3.60), and an unclosed wound (OR = 2.51) were significantly associated with increased risk of developing MRONJ.

CONCLUSIONS

We recommend a minimally traumatic extraction technique, removal of any bone edges, and mucosal wound closure as standard procedures in patients receiving bisphosphonates. We find no evidence supporting the efficacy of a pre-extraction short-term drug holiday from oral bisphosphonates in reducing the risk of MRONJ.