Patterns, timing and predictors of recurrence following pancreaticoduodenectomy for distal cholangiocarcinoma: An international multicentre retrospective cohort study

INTRODUCTION

Patients undergoing pancreaticoduodenectomy for distal cholangiocarcinoma (dCCA) often develop cancer recurrence. Establishing timing, patterns and risk factors for recurrence may help inform surveillance protocol strategies or select patients who could benefit from additional systemic or locoregional therapies. This multicentre retrospective cohort study aimed to determine timing, patterns, and predictive factors of recurrence following pancreaticoduodenectomy for dCCA.

MATERIALS AND METHODS

Patients who underwent pancreaticoduodenectomy for dCCA between June 2012 and May 2015 with five years of follow-up were included. The primary outcome was recurrence pattern (none, local-only, distant-only or mixed local/distant). Data were collected on comorbidities, investigations, operation details, complications, histology, adjuvant and palliative therapies, recurrence-free and overall survival. Univariable tests and regression analyses investigated factors associated with recurrence.

RESULTS

In the cohort of 198 patients, 129 (65%) developed recurrence: 30 (15%) developed local-only recurrence, 44 (22%) developed distant-only recurrence and 55 (28%) developed mixed pattern recurrence. The most common recurrence sites were local (49%), liver (24%) and lung (11%). 94% of patients who developed recurrence did so within three years of surgery. Predictors of recurrence on univariable analysis were cancer stage, R1 resection, lymph node metastases, perineural invasion, microvascular invasion and lymphatic invasion. Predictors of recurrence on multivariable analysis were female sex, venous resection, advancing histological stage and lymphatic invasion.

CONCLUSION

Two thirds of patients have cancer recurrence following pancreaticoduodenectomy for dCCA, and most recur within three years of surgery. The commonest sites of recurrence are the pancreatic bed, liver and lung. Multiple histological features are associated with recurrence.

Do some patients receive unnecessary parenteral nutrition after pancreatoduodenectomy? Results from an international multicentre study

Backgrounds/Aims

After pancreatoduodenectomy (PD), an early oral diet is recommended; however, the postoperative nutritional management of PD patients is known to be highly variable, with some centers still routinely providing parenteral nutrition (PN). Some patients who receive PN experience clinically significant complications, underscoring its judicious use. Using a large cohort, this study aimed to determine the proportion of PD patients who received postoperative nutritional support (NS), describe the nature of this support, and investigate whether receiving PN correlated with adverse perioperative outcomes.

Methods

Data were extracted from the Recurrence After Whipple's study, a retrospective multicenter study of PD outcomes.

Results

In total, 1,323 patients (89%) had data on their postoperative NS status available. Of these, 45% received postoperative NS, which was "enteral only," "parenteral only," and "enteral and parenteral" in 44%, 35%, and 21% of cases, respectively. Body mass index < 18.5 kg/m2 (p = 0.03), absence of preoperative biliary stenting (p = 0.009), and serum albumin < 36 g/L (p = 0.009) all correlated with receiving postoperative NS. Among those who did not develop a serious postoperative complication, i.e., those who had a relatively uneventful recovery, 20% received PN.

Conclusions

A considerable number of patients who had an uneventful recovery received PN. PN is not without risk, and should be reserved for those who are unable to take an oral diet. PD patients should undergo pre- and postoperative assessment by nutrition professionals to ensure they are managed appropriately, and to optimize perioperative outcomes.

Does an extensive diagnostic workup for upfront resectable pancreatic cancer result in a delay which affects survival? Results from an international multicentre study

Backgrounds/Aims

Pancreatoduodenectomy (PD) is recommended in fit patients with a carcinoma (PDAC) of the pancreatic head, and a delayed resection may affect survival. This study aimed to correlate the time from staging to PD with long-term survival, and study the impact of preoperative investigations (if any) on the timing of surgery.

Methods

Data were extracted from the Recurrence After Whipple's (RAW) study, a multicentre retrospective study of PD outcomes. Only PDAC patients who underwent an upfront resection were included. Patients who received neoadjuvant chemo-/radiotherapy were excluded. Group A (PD within 28 days of most recent preoperative computed tomography [CT]) was compared to group B (> 28 days).

Results

A total of 595 patents were included. Compared to group A (median CT-PD time: 12.5 days, interquartile range: 6-21), group B (49 days, 39-64.5) had similar one-year survival (73% vs. 75%, p = 0.6), five-year survival (23% vs. 21%, p = 0.6) and median time-todeath (17 vs. 18 months, p = 0.8). Staging laparoscopy (43 vs. 29.5 days, p = 0.009) and preoperative biliary stenting (39 vs. 20 days, p < 0.001) were associated with a delay to PD, but magnetic resonance imaging (32 vs. 32 days, p = 0.5), positron emission tomography (40 vs. 31 days, p > 0.99) and endoscopic ultrasonography (28 vs. 32 days, p > 0.99) were not.

Conclusions

Although a treatment delay may give rise to patient anxiety, our findings would suggest this does not correlate with worse survival. A delay may be necessary to obtain further information and minimize the number of PD patients diagnosed with early disease recurrence.

Anticoagulation after pancreatic surgery with venous resection (TIGRESS): What should we do? Results from an international survey

Backgrounds/Aims

Patients who undergo pancreatic surgery with venous resection have high rates of morbidity/mortality. Also, they are high-risk for postoperative venous thromboembolism. Whether this group should be routinely anticoagulated is unknown. This study aimed to establish current anticoagulation practices.

Methods

A survey (https://form.jotform.com/220242489107048) was sent out to pancreatic surgeons. Questions covered center volume, venous resection/reconstruction techniques and anticoagulation policies.

Results

Sixty-five centers from 17 countries responded. Following a "side-bite" venous resection with a patch repair, 40% used an autologous vein patch, 27% used peritoneum, and 27% used a bovine patch. After formally resecting a segment of vein, 17% of centers used an interposition graft (IG). Left renal vein (41%) and polytetrafluoroethylene (73%) grafts were the most commonly used autologous and prosthetic IGs, respectively. Following a prosthetic IG, an autologous IG, and a "side-bite" resection, 59%, 28%, and 19% of centers provided therapeutic anticoagulation, respectively (66% used low molecular-weight heparin). The duration of therapy provided varied from inpatient stay only (14%) to six months (32%).

Conclusions

Our global survey indicates that anticoagulation practices are highly variable. Centers do not agree on when to anticoagulate, how to anticoagulate, or the duration of therapy. A robust trial is required to provide clarity.

Postoperative complications after pancreatoduodenectomy for malignancy: results from the Recurrence After Whipple's (RAW) study

BACKGROUND

Pancreatoduodenectomy (PD) is associated with significant postoperative morbidity. Surgeons should have a sound understanding of the potential complications for consenting and benchmarking purposes. Furthermore, preoperative identification of high-risk patients can guide patient selection and potentially allow for targeted prehabilitation and/or individualized treatment regimens. Using a large multicentre cohort, this study aimed to calculate the incidence of all PD complications and identify risk factors.

METHOD

Data were extracted from the Recurrence After Whipple's (RAW) study, a retrospective cohort study of PD outcomes (29 centres from 8 countries, 2012-2015). The incidence and severity of all complications was recorded and potential risk factors for morbidity, major morbidity (Clavien-Dindo grade > IIIa), postoperative pancreatic fistula (POPF), post-pancreatectomy haemorrhage (PPH) and 90-day mortality were investigated.

RESULTS

Among the 1348 included patients, overall morbidity, major morbidity, POPF, PPH and perioperative death affected 53 per cent (n = 720), 17 per cent (n = 228), 8 per cent (n = 108), 6 per cent (n = 84) and 4 per cent (n = 53), respectively. Following multivariable tests, a high BMI (P = 0.007), an ASA grade > II (P < 0.0001) and a classic Whipple approach (P = 0.005) were all associated with increased overall morbidity. In addition, ASA grade > II patients were at increased risk of major morbidity (P < 0.0001), and a raised BMI correlated with a greater risk of POPF (P = 0.001).

CONCLUSION

In this multicentre study of PD outcomes, an ASA grade > II was a risk factor for major morbidity and a high BMI was a risk factor for POPF. Patients who are preoperatively identified to be high risk may benefit from targeted prehabilitation or individualized treatment regimens.

Serious complications of pancreatoduodenectomy correlate with lower rates of adjuvant chemotherapy: Results from the recurrence after Whipple's (RAW) study

INTRODUCTION

Adjuvant chemotherapy (AC) can prolong overall survival (OS) after pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC). However, fitness for AC may be influenced by postoperative recovery. We aimed to investigate if serious (Clavien-Dindo grade ≥ IIIa) postoperative complications affected AC rates, disease recurrence and OS.

MATERIALS AND METHODS

Data were extracted from the Recurrence After Whipple's (RAW) study (n = 1484), a retrospective study of PD outcomes (29 centres from eight countries). Patients who died within 90-days of PD were excluded. The Kaplan-Meier method was used to compare OS in those receiving or not receiving AC, and those with and without serious postoperative complications. The groups were then compared using univariable and multivariable tests.

RESULTS

Patients who commenced AC (vs no AC) had improved OS (median difference: (MD): 201 days), as did those who completed their planned course of AC (MD: 291 days, p < 0.0001). Those who commenced AC were younger (mean difference: 2.7 years, p = 0.0002), more often (preoperative) American Society of Anesthesiologists (ASA) grade I-II (74% vs 63%, p = 0.004) and had less often experienced a serious postoperative complication (10% vs 18%, p = 0.002). Patients who developed a serious postoperative complication were less often ASA grade I-II (52% vs 73%, p = 0.0004) and less often commenced AC (58% vs 74%, p = 0.002).

CONCLUSION

In our multicentre study of PD outcomes, PDAC patients who received AC had improved OS, and those who experienced a serious postoperative complication commenced AC less frequently. Selected high-risk patients may benefit from targeted preoperative optimisation and/or neoadjuvant chemotherapy.

Pancreatoduodenectomy for suspected malignancy: nonmalignant histology confers increased risk of serious morbidity

BACKGROUND/AIMS

A tissue diagnosis is not always obtained prior to pancreatoduodenectomy (PD) and a proportion of patients are found to have noncancerous histology postoperatively. It is unknown if these patients have different outcomes when compared with those who have malignancy confirmed.

METHODS

A retrospective paired case matched control study was undertaken. Patients who underwent PD for suspected malignancy but ultimately had nonmalignant histology were identified. Each was matched to a confirmed malignant control using the following criteria: age, gender, body mass index, American Society of Anesthesiologists grade, neoadjuvant treatment, preoperative serum bilirubin, preoperative biliary stenting and type of pancreatic anastomosis. Matching was blinded to the measured outcomes, which included perioperative morbidity and mortality.

RESULTS

Forty-five cases were compared with 45 well-matched controls. There was no difference in 30- or 90-day mortality, or length of stay. While overall morbidity rates were the same, patients with nonmalignant disease were more likely to experience major (Clavien-Dindo grade III-IV) morbidity (40.0% versus 17.8%, p = 0.0352). Independently, rates of clinically relevant pancreatic fistula (CR-POPF) were higher in the nonmalignant group (22.2% versus 4.44%, p = 0.0131).

CONCLUSIONS

In our study, PD patients with nonmalignant histology had significantly higher incidence of major morbidity and CR-POPF when compared with those who had malignancy confirmed. This should be considered when planning the management of patients with known or presumed benign/premalignant disease.

Predictors of actual five-year survival and recurrence after pancreatoduodenectomy for ampullary adenocarcinoma: results from an international multicentre retrospective cohort study

BACKGROUND

Pancreatoduodenectomy (PD) is recommended in fit patients with a resectable ampullary adenocarcinoma (AA). We aimed to identify predictors of five-year recurrence/survival.

METHODS

Data were extracted from the Recurrence After Whipple's (RAW) study, a multicentre retrospective study of PD patients with a confirmed head of pancreas or periampullary malignancy (June 1st, 2012-May 31st, 2015). Patients with AA who developed recurrence/died within five-years were compared to those who did not.

RESULTS

394 patients were included and actual five-year survival was 54%. Recurrence affected 45% and the median time-to-recurrence was 14 months. Local only, local and distant, and distant only recurrence affected 34, 41 and 94 patients, respectively (site unknown: 7). Among those with recurrence, the most common sites were the liver (32%), local lymph nodes (14%) and lung/pleura (13%). Following multivariable tests, number of resected nodes, histological T stage > II, lymphatic invasion, perineural invasion (PNI), peripancreatic fat invasion (PPFI) and ≥1 positive resection margin correlated with increased recurrence and reduced survival. Furthermore, ≥1 positive margin, PPFI and PNI were all associated with reduced time-to-recurrence.

CONCLUSIONS

This multicentre retrospective study of PD outcomes identified numerous histopathological predictors of AA recurrence. Patients with these high-risk features might benefit from adjuvant therapy.

Serious complications of pancreatoduodenectomy correlate with lower rates of adjuvant chemotherapy: Would high-risk patients benefit from neoadjuvant therapy?

INTRODUCTION

Patients who suffer a serious complication of pancreatoduodenectomy (PD) may have their adjuvant chemotherapy (AC) delayed or omitted as a result. We aimed to investigate whether PD complications affected AC rates.

MATERIALS AND METHODS

A retrospective analysis of all PD patients with histologically-confirmed pancreatic ductal adenocarcinoma (2006-2015) was performed; 90-day mortality patients were excluded. Patients who commenced AC were compared to those who did not (morbidity rates and survival) and patients who developed selected postoperative complications were compared to those who did not (AC rates and survival).

RESULTS

157 patients were included and 90-day mortality was 3.8%. Of the remaining patients, 102 (68.5%) received AC (AC data unavailable for two patients). Survival was longer in the AC group (p = 0.004). AC patients had less frequently experienced a postoperative chest infection (8.82% vs 34.0%, p = 0.0003) or a postoperative complication which was Clavien-Dindo (CD) grade ≥ II (29.4% vs 57.4%, p = 0.0019) or ≥ III (6.86% vs 21.3%, p = 0.023). Patients who experienced a postoperative chest infection (36.0% vs 75.0%, p = 0.0003) or a postoperative complication which was CD grade ≥ II (48.9% vs 73.1%, p = 0.0099) or ≥ III (29.4% vs 70.3%, p = 0.0018) less frequently commenced AC.

CONCLUSION

Patients who received AC had less frequently experienced a serious postoperative complication. Efforts should be made to preoperatively identify those who are high-risk for a serious complication as this cohort may benefit from neoadjuvant therapy.

Implementation of a provider-focused intervention for maximizing human papillomavirus (HPV) vaccine uptake in young cancer survivors receiving follow-up care in pediatric oncology practices: protocol for a cluster-randomized trial of the HPV PROTECT intervention

Background

Childhood cancer survivors are at high risk for developing new cancers (such as cervical and anal cancer) caused by persistent infection with the human papillomavirus (HPV). HPV vaccination is effective in preventing the infections that lead to these cancers, but HPV vaccine uptake is low among young cancer survivors. Lack of a healthcare provider recommendation is the most common reason that cancer survivors fail to initiate the HPV vaccine. Strategies that are most successful in increasing HPV vaccine uptake in the general population focus on enhancing healthcare provider skills to effectively recommend the vaccine, and reducing barriers faced by the young people and their parents in receiving the vaccine. This study will evaluate the effectiveness and implementation of an evidence-based healthcare provider-focused intervention (HPV PROTECT) adapted for use in pediatric oncology clinics, to increase HPV vaccine uptake among cancer survivors 9 to 17 years of age.

Methods

This study uses a hybrid type 1 effectiveness-implementation approach. We will test the effectiveness of the HPV PROTECT intervention using a stepped-wedge cluster-randomized trial across a multi-state sample of pediatric oncology clinics. We will evaluate implementation (provider perspectives regarding intervention feasibility, acceptability and appropriateness in the pediatric oncology setting, provider fidelity to intervention components and change in provider HPV vaccine-related knowledge and practices [e.g., providing vaccine recommendations, identifying and reducing barriers to vaccination]) using a mixed methods approach.

Discussion

This multisite trial will address important gaps in knowledge relevant to the prevention of HPV-related malignancies in young cancer survivors by testing the effectiveness of an evidence-based provider-directed intervention, adapted for the pediatric oncology setting, to increase HPV vaccine initiation in young cancer survivors receiving care in pediatric oncology clinics, and by procuring information regarding intervention delivery to inform future implementation efforts. If proven effective, HPV PROTECT will be readily disseminable for testing in the larger pediatric oncology community to increase HPV vaccine uptake in cancer survivors, facilitating protection against HPV-related morbidities for this vulnerable population.

Trial registration

ClinicalTrials.gov Identifier: NCT04469569, prospectively registered on July 14, 2020.

Results from a UK-wide survey: the nutritional assessment and management of pancreatic resection patients is highly variable

Most patients who undergo curative-intent resection for pancreatic cancer are malnourished. This correlates with poor outcomes. There are no guidelines for the nutritional management of these patients. We aimed to establish current UK practice by surveying all hepatopancreatobiliary (HPB) units. Questions covered: dietetic service, nutrition risk screening (RS), micronutrients, prehabilitation, nutritional support, pancreatic exocrine replacement therapy (PERT), and details of follow-up. Twenty-six units (83.9%) responded. Twenty-three (88.5%) provide a specialist HPB dietetic service. Twelve (52.2%) cover the entire treatment pathway. Thirteen (50.0%) routinely perform RS, eleven (42.3%) check micronutrients, and fourteen (53.8%) provide a prehabilitation programme. Twelve units (46.2%) allow nutritional supplements within 48 h of surgery, and eight (30.8%) do not allow this until at least 72 h. The use of PERT and acid-suppressing agents is highly variable. Seventeen units (65.4%) routinely provide dietitian follow-up. Practice is highly variable; robust studies are required so consensus guidelines can be formulated.

How we do it: Laparoscopic cholecystectomy in patients with severe obesity

The number of patients with obesity is set to rise, as is the proportion with severe obesity. These patients are a high-risk subgroup who present addi- tional challenges to the surgeon when performing laparoscopic cholecystectomy. It is important that all surgeons who perform this procedure have a safe strategy they can revert to. This article outlines our approach. After obtaining pneumoperitoneum via a supra-umbilical incision, we advise placing a fascial suture before proceeding with the operation. This allows for high-quality closure, reduces the incidence of incisional hernia, and reduces the risk of inadvertent bowel injury. We also advise the repositioning of the patient on the operating table prior to port placement such that an ergonomic set-up can be achieved. In addition to standard ports, we use an additional twelve-millimetre port in the left upper quadrant. A fan retractor can be inserted via this port and used to gently retract the duodenum inferiorly. This provides adequate exposure for Calot’s dissection and arguably reduces the risk of injury to a fatty liver. This technique can also be used in non-obese patients in whom Calot’s dissection is particularly challenging, for instance in those who undergo delayed cholecystectomy.

A date pit induced aorto-oesophageal fistula: a case report and concise literature review

Aorto-oesophageal fistula (AEF) is rare and fatal without intervention. Having consumed a date pit 2 weeks prior, the patient in this case presented with the ‘Chiari’ triad of chest pain, sentinel arterial upper gastro-intestinal haemorrhage and exsanguination after an asymptomatic interval. Following resuscitation, the patient was managed with a Blakemore tube with both oesophageal and gastric balloons inflated to systemic pressures. An aortic stent graft was planned but the patient died on the operating table.

AEFs can be treated surgically with either open or endovascular repair. Open repair is highly risky and involves combined replacement/bypass of the thoracic aorta along with resection/repair of the involved oesophagus. Endovascular repair can prevent fatal exsanguination and increase the likelihood of survival but is associated with a significant rate of secondary infection, recurrence of fistula, mediastinitis and sepsis. Further studies are required to inform on management.

Emergency hernia surgery at a high-volume tertiary centre: a 3-year experience

BACKGROUND

Hernia surgery is often considered minor. However, emergency abdominal wall hernia (AWH) surgery is associated with significant morbidity. This study reviews a high-volume centre's experience.

METHODS

This is a retrospective review of all emergency AWH operations performed between 2014 and 2017. The following were analysed: patient demographics, ASA grade, type of hernia, time from admission to surgery, use of pre-operative imaging, sac content, details of bowel resection, rate of admission to high dependency unit (HDU)/intensive care unit (ICU), length of stay and morbidity/mortality.

RESULTS

A total of 198 cases were included. Median age was 67.4 years (range 19-95). 52.2% of patients were ASA III or above. Median time from admission to surgery was 13 h (range 1-341) and median length of stay was 4 days (range 1-75). The sac contained bowel in 93 cases (47.0%). These patients had longer length of stay (P < 0.01) and were more frequently admitted to HDU/ICU (P < 0.01). Thirty-one patients underwent bowel resection (33.3% of those with bowel involvement and 15.7% of the total). Twenty-seven patients (13.6%) were admitted to HDU/ICU post-operatively. Six patients (3.0%) had an unplanned return to theatre and 66 patients (33.3%) had a post-operative complication. Inpatient mortality was three (1.51%).

CONCLUSIONS

Patients who undergo emergency AWH surgery represent a relatively aged and co-morbid group. This surgery is associated with significant morbidity and consumes considerable hospital resources. Efforts should be made to identify the higher risk subgroup with bowel involvement. Elderly and co-morbid patients should be listed for timely elective surgery wherever suitable.

Pneumocystis Jirovecii Pneumonia During Sirolimus Therapy for Kaposiform Hemangioendothelioma

Sirolimus is an effective therapy for children with kaposiform hemangioendothelioma with or without the Kasabach-Merritt phenomenon. We report the case of a child with kaposiform hemangioendothelioma and the Kasabach-Merritt phenomenon who developed Pneumocystis carinii pneumonia (PCP) while on sirolimus and a prednisolone taper, after lack of adequate response to prednisolone, propranolol, and vincristine. He had a prompt positive clinical and laboratory response to sirolimus, but 4 weeks after starting it, at the age of 4 months, he developed PCP. This led to respiratory failure, which required extracorporeal membrane oxygenation. Sirolimus was temporarily discontinued, and he was successfully treated for PCP with sulfamethoxazole-trimethoprim and methylprednisolone. He was restarted on sirolimus 3 weeks after discharge and given sulfamethoxazole-trimethoprim prophylaxis. At the age of 22 months, while still on sirolimus, the lesion continued to improve with test results revealing stable hemoglobin and platelet counts. PCP is a rare but life-threatening side effect of sirolimus therapy, especially in the setting of concurrent steroid treatment. Pneumocystis prophylaxis should be considered for patients receiving sirolimus.

Association of Obesity and Pediatric Venous Thromboembolism

BACKGROUND

The incidence of venous thromboembolism (VTE) is increasing among pediatric patients in the United States. Previous studies on obesity as a risk factor have produced mixed results.

METHODS

We completed a retrospective chart review of patients aged 2 to 18 years with VTE identified by using International Classification of Diseases, Ninth Revision, codes and confirmed by imaging. Patients were admitted between January 2000 and September 2012. Control subjects were matched on age, gender, and the presence of a central venous catheter. Data were collected on weight, height, and risk factors, including bacteremia, ICU admission, immobilization, use of oral contraceptives, and malignancy. Underweight patients and those without documented height and weight data were excluded. Independent predictors of VTE risk were identified by using univariate and multivariate analyses.

RESULTS

We identified 88 patients plus 2 matched control subjects per case. The majority of cases were nonembolic events (77%) of the lower extremity (25%) or head and neck (22%) confirmed by ultrasound (43%) or computed tomography scan (41%). A statistically significant association was found between VTE and increased BMI z score (P = .002). In multivariate analysis, BMI z score (odds ratio [OR]: 3.1; P = .007), bacteremia (OR: 4.9; P = .02), ICU stay (OR: 2.5; P = .02), and use of oral contraceptives (OR: 17.4; P < .001) were significant predictors.

CONCLUSIONS

In this single-institution study, the diagnosis of VTE was significantly associated with overweight and obesity. Further study is needed to fully define this association.

Fatal carboplatin-induced immune hemolytic anemia in a child with a brain tumor

Drug-induced immune hemolytic anemia (DIIHA) is an uncommon side effect of pharmacologic intervention. A rare mediator of DIIHA, carboplatin is an agent used to treat many pediatric cancers. We describe here, the first case of fatal carboplatin induced DIIHA in a pediatric patient and a brief review of the literature. Our patient developed acute onset of multi-organ failure with evidence of complement activation, secondary to a drug induced red cell antibody. Early recognition of the systemic insult associated with carboplatin induced hemolytic anemia may allow for future affected patients to receive plasmapheresis, a potentially effective therapy.

dic(7;9)(p11-13;p11)

Dicentric (7;9)(p11-13;p11) is a rare but recurrent abnormality in pediatric and adult precursor B acute lymphoblastic leukemia (B-ALL). The rarity precludes a deep understanding of its biology and associated prognosis. However, recent findings have correlated dic(7;9) and PAX5 mutations, highlighting this cytogenetic event's involvement in leukemogenesis and may also shed light on the overall prognosis of dic(7;9) B-ALL.