Paraaortic Extra-Adrenal Paraganglioma: Challenging Robotic Resection

BACKGROUND

Up to 41% of intra- and extra-adrenal paragangliomas are linked to germline mutations with autosomal dominant transmission, which necessitates genetic testing for patients and their relatives.1-4 Certain alterations, such as the succinate dehydrogenase (SDH) subunit B gene mutation, are associated with a significant risk of extra-adrenal, malignant, and metastatic disease forms.4-7 This highlights the need for routine genetic counseling and diligent surveillance, as well as surgeon awareness of hereditary paraganglioma-pheochromocytoma syndrome (HPPS).

METHODS

We present a multimedia article featuring a step-by-step video of a complex retroperitoneal resection, enriched with perioperative management insights.

RESULTS

A 17-year-old female presented with episodes of hypertension, tachycardia, and diffuse diaphoresis. CT revealed a paraaortic mass adjacent to the left renal hilum later confirmed by a SPECT/CT with iodine-123 meta-iodobenzylguanidine.8 Additional imaging with gallium-68 DOTATATE was not performed then due to unknown mutation status. The patient underwent robotic removal of the tumor and adjacent lymph nodes. Pathology confirmed a poorly differentiated paraganglioma with 0/6 lymph node metastases. Genetic tests revealed SDHB gene mutation, indicative of HPPS.9,10 At 12 months, the patient remained disease-free on CT with normalized metanephrines levels and no detectable circulating tumor DNA. Familial screening detected her mother, maternal uncle, and maternal grandfather to be SDHB mutation carriers, although phenotypically silent.

CONCLUSIONS

Robotic-assisted resection can be safe and effective for retroperitoneal malignant paragangliomas. However, management extends beyond surgery and requires cascade genetic testing to address familial risks. Because of the high probability of cancer associated with SDHB mutation, lifelong patient surveillance is imperative.

Sufficient Regional Lymph Node Examination for Staging Adenocarcinoma of the Appendix

BACKGROUND

The presence of lymph node (LN) metastasis is a known negative prognostic factor in appendix cancer (AC) patients. However, currently the minimum number of LNs required to adequately determine LN negativity is extrapolated from colorectal studies and data specific to AC is lacking. We aimed to define the lowest number of LNs required to adequately stage AC and assess its impact on oncologic outcomes.

METHODS

Patients with stage II-III AC from the National Cancer Database (NCDB 2004-2019) undergoing surgical resection with complete information about LN examination were included. Multivariable logistic regression assessed the odds of LN positive (LNP) disease for different numbers of LNs examined. Multivariable Cox regressions were performed by LN status subgroups, adjusted by prognostic factors, including grade, histologic subtype, surgical approach, and documented adjuvant systemic chemotherapy.

RESULTS

Overall, 3,602 patients were included, from which 1,026 (28.5%) were LNP. Harvesting ten LNs was the minimum number required without decreased odds of LNP compared with the reference category (≥ 20 LNs). Total LNs examined were < 10 in 466 (12.9%) patients. Median follow-up from diagnosis was 75.4 months. Failing to evaluate at least ten LNs was an independent negative prognostic factor for overall survival (adjusted hazard ratio 1.39, p < 0.01).

CONCLUSIONS

In appendix adenocarcinoma, examining a minimum of ten LNs was necessary to minimize the risk of missing LNP disease and was associated with improved overall survival rates. To mitigate the risk of misclassification, an adequate number of regional LNs must be assessed to determine LN status.

Collaborative expertise of gynecological and surgical oncologists in managing advanced epithelial ovarian cancer

BACKGROUND

Most patients with epithelial ovarian cancer (EOC) present with significant peritoneal spread. We assessed collaborative efforts of surgical and gynecological oncologists with expertise in cytoreductive surgery (CRS) in the management of advanced EOC.

METHODS

Using a prospective single-center database (2014-2022), we described the operative and oncologic outcomes of stage IIIC-IVA primary and recurrent EOC perioperatively managed jointly by gynecological and surgical oncologists both specializing in CRS and presented components of this collaboration.

RESULTS

Of 199 identified patients, 132 (66 %) had primary and 53 (27 %) had recurrent EOC. Due to inoperable disease, 14 (7 %) cases were aborted and excluded from analysis. Median peritoneal cancer index (PCI) in primary and recurrent patients was 21 (IQR: 11-28) and 21 (IQR: 6-31). Upper abdominal surgery was required in 95 % (n = 125) of primary and 89 % (n = 47) of recurrent patients. Bowel resections were performed in 83 % (n = 110) and 72 % (n = 38), respectively. Complete cytoreduction (CC-0/1) with no disease or residual lesions <2.5 mm was achieved in 95 % (n = 125) of primary and 91 % (n = 48) of recurrent patients. Ninety-day Clavien-Dindo grade III-IV morbidity was 12 % (n = 16) and 21 % (n = 11), respectively. Median follow-up was 44 (95%CI: 33-55) months. Median overall survival in primary and recurrent EOC was 68 (95%CI: 45-91) and 50 (95%CI: 16-84) months. Median progression-free survival was 26 (95%CI: 22-30) and 14 (95%CI: 7-21) months, respectively.

CONCLUSIONS

Perioperative collaboration between surgical and gynecological oncologists specializing in CRS allows safe performance of complete cytoreduction in the majority of patients with primary and recurrent EOC, despite high tumor burden.

Building an Efficient Peritoneal Surface Malignancies Program Despite the Lower-Middle-Income Barriers: Ukraine Experience

PURPOSE

Cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) programs are often limited to centers in developed countries because of extensive requirements. We aimed to analyze efficacy and challenges of CRS/HIPEC centers in lower-middle-income settings in the Ukraine example.

METHODS

A multicenter descriptive study was conducted using data sets (2008-2022) from Kyiv, Lviv, and Odesa centers. Patients with appendiceal neoplasm (AN); colorectal cancer (CRC); malignant peritoneal mesothelioma (MPM); and epithelial ovarian, fallopian tube, and primary peritoneal cancer (EOC) treated with CRS ± HIPEC were included. Overall survival (OS) was analyzed for N ≥ 20 cohorts using the Kaplan-Meier method.

RESULTS

We included 596 patients. At Kyiv and Lviv centers, 37 and 28 patients with AN had completeness of cytoreduction (CC-0/1) rates of 84% and 71%, respectively. Thirty-day major morbidity stood at 24% and 18%, respectively. Median OS was not reached (NR) at both centers. Nineteen patients with CRC from Kyiv, 11 from Lviv, and 156 from Odesa had CC-0/1 rates of 84%, 91%, and 86%, respectively. Thirty-day major complications occurred in 16%, 18%, and 8%, respectively. Median OS in the Odesa cohort was 35 (95% CI, 32 to 38) months. Among 15 Kyiv, five Lviv, and six Odesa patients with MPM, CC-0/1 rates were 67%, 80%, and 100%, respectively, while major complications occurred in 13%, 0%, and 17%, respectively. OS was not analyzed because of small MPM cohorts. At Kyiv, Lviv, and Odesa centers, 91, 40, and 89 patients, respectively, had primary EOC. CC-0/1 rates were 79%, 100%, and 80%, and 30-day major morbidity rates were 23%, 5%, and 6%, respectively. Median OS was NR, 71 (95% CI, 32 to 110), and 67 (95% CI, 61 to 73) months, respectively.

CONCLUSION

CRS/HIPEC programs in lower-middle-income environment can achieve safety and survival that meet global standards. Our discussion highlights common obstacles in such settings and proposes effective overcoming strategies.

Patterns of Recurrence in Appendix Cancer After Complete Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

It is thought that low-grade (LG) appendiceal cancer (AC) demonstrates predominantly intraperitoneal recurrence (IPR) after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC), whereas high-grade (HG) tumors progress both intra- and extraperitoneally (EPR). However, evidence supporting this conception is lacking; therefore, we assessed recurrence in various AC histologies.

METHODS

A retrospective, cohort study was conducted by using a single-center database (1998-2022). Recurrence patterns (IPR, EPR, combined) were identified for LG, HG, high-grade with signet ring cells (SRC), and goblet cell carcinoma (GCC).

RESULTS

We included 432 complete (CC-0/1) CRS/HIPECs: 200 LG, 114 HG, 72 SRC, and 46 GCC. Median follow-up was 78 (95% confidence interval [CI] 70-86) months. Overall, 34% (n = 148) of patients recurred. IPR was the most common (LG 16%, HG 27%, SRC 36%, GCC 26%) with median time to recurrence (MTR) of 21 (IQR: 12-40) months. EPR (liver, lung, pleura, lymph nodes, or bones) occurred in LG 3%, HG 9%, SRC 22%, and GCC 7%. MTR was 11 (IQR: 4-16) months. Combined pattern occurred in LG 0%, HG 8%, SRC 7%, and GCC 0%. MTR was 13 (IQR: 7-18) months. Iterative surgery was performed in 53% IPR, 18% EPR, and 51% combined. Median post-recurrence survival was longer after IPR compared with EPR and combined recurrence: 36 (95% CI 25-47) versus 13 (95% CI 7-19) and 18 (95% CI 6-30) months (p < 0.01).

CONCLUSIONS

After complete CRS/HIPEC, IPR was the predominant pattern in all AC histologies and occurred later. Post-recurrence survival after IPR was longer. Knowing AC recurrence patterns can help to understand its biology and plan follow-up and post-relapse management.

Outcomes after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal dissemination from ovarian carcinosarcoma

BACKGROUND

Ovarian carcinosarcoma (OCS) is an uncommon and aggressive malignancy, with poor response to current treatment approaches and no clear guidelines. Our aim is to evaluate the outcomes of an OCS cohort after cytoreduction with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC).

METHODS

A descriptive cohort study was performed. Patients who underwent CRS/HIPEC for peritoneal dissemination from tubo-ovarian malignancies (1999-2021) were retrospectively reviewed. Patients with confirmed histopathologic diagnosis of FIGO stage III/IV OCS were included. Overall (OS) and progression-free survival (PFS) were determined with the Kaplan-Meier method.

RESULTS

Of 267 patients with tubo-ovarian malignancies reviewed, 7.5% (20/267) had OCS. Of these, 16 underwent CRS/HIPEC, including 9 for a new diagnosis and 7 for disease recurrence. Median age at surgery was 66.5 (IQR: 54.5-74.5) years. Nine (56.2%) patients were FIGO stage IV. Median peritoneal cancer index was 22 (IQR: 14-28). Complete cytoreduction was achieved in 15/16 (93.7%) cases. HIPEC agents included carboplatin (n = 7), cisplatin+doxorubicin (n = 4), and melphalan (n = 5). Major complications occurred in 4/16 (25%), with no 90-day mortality. Median follow-up was 41.8 months. Median PFS was 11.7 (95%CI: 10.5-17.1) months. Malignant bowel obstruction occurred in 3/16 (18.7%). Median OS from CRS/HIPEC was 21.3 (95%CI: 16.3-31.6) months, not reached for newly diagnosed vs 19.7 months for recurrent patients (p = 0.23).

CONCLUSIONS

CRS/HIPEC showed promising survival and abdominal disease control with low rates of malignant obstruction in patients with advanced stage OCS. Collaborative studies with larger cohorts and longer follow-up may further elucidate the role of CRS/HIPEC in OCS.

Safety of Nephrectomy Performed During CRS/HIPEC: A Propensity Score-Matched Study

BACKGROUND

Surgeons may hesitate to perform nephrectomy (NE) during cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) due to a potential increase in morbidity. However, no data are available regarding the impact of NE on outcomes, so the authors decided to assess its safety during CRS/HIPEC.

METHODS

A single-center propensity score-matched study was conducted using a prospective database (1994-2021). The study included patients who underwent NE during CRS/HIPEC with completeness of cytoreduction (CC) of 0, 1, or 2. Control subjects (no-NE) were selected in a 1:3 ratio using propensity score-matching weighted by age, histology, peritoneal cancer index (PCI), CC-0 or CC-1 rate, and length of surgery.

RESULTS

Among 828 patients, 13 NE and 39 no-NE control subjects were identified. The indications for NE included tumor involvement of the ureter, hilum, and/or kidney with preserved (n = 8), decreased (n = 2), or absent (n = 3) function. NE patients received more intraoperative intravenous (IV) fluids (16,000 vs 11,500 mL; p = 0.045) and had a greater urine output (3200 vs 1913 mL; p = 0.008). NE patients received mitomycin C (40 mg for 90 min) or melphalan (50 mg/m² for 90 min) without reduction of dose or time. Major morbidity (p = 0.435) and mortality (p = 1.000) were comparable between the two groups. No postoperative acute kidney injury was seen in either group. Adjuvant chemotherapy was administered to 46.2% of the NE and 35.9% of the no-NE patients (p = 0.553), with similar starting times (p = 0.903) between the groups.

CONCLUSIONS

Nephrectomy performed during CRS/HIPEC does not seem to increase postoperative morbidity or to delay adjuvant chemotherapy, and NE can be performed if required for complete cytoreduction. The NE patients in our cohort did not have a reduction of mitomycin C or melphalan dose or perfusion time.

Adjuvant chemotherapy for high-grade appendiceal cancer after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

INTRODUCTION

There are no available data on the efficacy of adjuvant chemotherapy (ACT) in stage IVA/B high-grade mucinous appendiceal cancer treated with CRS/HIPEC. We evaluated the association between ACT and survival in this cohort.

MATERIALS AND METHODS

A single-institution retrospective cohort study using a prospective database was conducted. Stage IVA/B high-grade mucinous appendiceal cancer patients who underwent CRS/HIPEC with CC-0/1 were included. Survival was compared between ACT and no chemotherapy (NoCT) patients. Subgroup analysis was performed with adjustment for confounding variables.

RESULTS

We identified 180 patients: 77 ACT and 103 NoCT. ACT regimens included 5-FU/capecitabine (13%), oxaliplatin-based (63%), and irinotecan-based (21%), combined with bevacizumab in 27% of cases. Median number of cycles was 9 (IQR: 6-12). Median overall survival (OS) did not significantly differ between ACT and NoCT (53 vs 75 months, p = 0.566). Multivariable Cox regression showed no OS benefit for ACT vs NoCT in patients with neoadjuvant chemotherapy (HR 1.14; 95%CI: 0.38-3.39) or without it (HR 1.33; 95%CI: 0.69-2.57), with signet ring cell (HR 0.89; 95%CI: 0.38-2.06) or other histologies (HR 1.11; 95%CI: 0.50-2.46), positive lymph nodes (HR 1.60; 95%CI: 0.74-3.49), or peritoneal cancer index ≥20 (HR 1.08; 95%CI: 0.55-2.11) after adjusting for other factors.

CONCLUSIONS

In our cohort, colon-type ACT was not associated with better OS in stage IVA/B mucinous appendiceal cancer after CRS/HIPEC, even after adjusting for confounders. This may be due to different tumor biology than colon cancer or small sample size. Prospective collaborative studies are needed.

Systemic Chemotherapy for High-Grade Mucinous Appendiceal Cancer with Peritoneal Spread After Unsuccessful CRS/HIPEC

BACKGROUND

The best management of patients who have unresectable mucinous appendiceal cancer (MAC) with peritoneal spread after a failed attempt at cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is unclear. This study aimed to assess outcomes after systemic chemotherapy (SCT) for patients with unresectable peritoneal metastases from high-grade MAC.

METHODS

A single-center retrospective cohort study was conducted using a prospective CRS/HIPEC database. The study included high-grade MAC patients with peritoneal carcinomatosis who were deemed surgical candidates, but had an aborted CRS/HIPEC or only palliative HIPEC due to unresectable disease. Overall survival (OS) was compared.

RESULTS

Of 72 identified patients, 20 received SCT and 52 did not (NoCT). The groups were balanced by age (p = 0.299), sex (p = 0.930), histopathologic subtype (p = 0.096), preoperative chemotherapy (p = 0.981), and postoperative major complication rates (p = 0.338). Both groups had extensive disease (median peritoneal cancer index at exploration, 39 vs 39). The median number of cycles was 12 (interquartile range [IQR], 6-15), and the median time between the procedure and SCT was 7 weeks (IQR, 5-10 weeks). The median follow-up period was 65 months. The median OS was significantly higher for the SCT group (26 months; 95 % confidence interval [CI], 10.8-41.5 months) than for the NoCT group (12 months; 95 % CI, 9.6-14.4 months) (p < 0.001), with hazard ratio (HR) of 0.22 (95 % CI, 0.08-0.66; p = 0.007) after adjustment for other factors.

CONCLUSION

Systemic chemotherapy is associated with improved OS for high-grade MAC patients with unresectable peritoneal metastases who are deemed surgical candidates but underwent an unsuccessful CRS/HIPEC attempt. Further prospective studies with a larger sample are required to identify patient subgroups who benefit the most from SCT.

Iterative Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy for Recurrent Mucinous Adenocarcinoma of the Appendix

BACKGROUND

Recurrence after cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for appendiceal tumors (AT) with mucinous carcinomatosis peritonei (MCP) is common. The evidence favoring iterative procedures (iCRS/HIPEC) is limited, and its benefit is not clear for all patients.

METHODS

Retrospective (1998-2020) cohorts of AT patients with MCP recurrence after the first CRS/HIPEC were analyzed. Outcomes were compared within tumor grades between iCRS/HIPEC patients and matched control patients without iCRS/HIPEC using propensity score matching (1:1). Post-recurrence survival (PRS) was measured from the date of recurrence after the first CRS/HIPEC to death or last contact.

RESULTS

Overall, 55 iCRS/HIPEC patients were identified: 36 low-grade (LGMCP) patients, 13 high-grade (HGMCP) patients, and 6 HGMCP patients with signet-ring features (HGMCP-S). Nine patients had a third CRS/HIPEC. The median peritoneal cancer index (PCI) scores were 33, 19 and 10, with CC-0/1 achieved for 94.4%, 78.2% and 88.9% of the patients after the first, second, and third CRS/HIPEC, respectively. No 90-day postoperative mortality occurred. The median progression-free survival from the first CRS/HIPEC was 19.7 months for the iCRS/HIPEC patients versus 14.2 months for the matched control patients (p = 0.43). The median PRS was 80.2 months for iCRS/HIPEC versus 36.2 for the control patients (p < 0.001). For the iCRS/HIPEC versus the matched control patients, the median PRS by tumor grade was 174.1 versus 51.9 (p < 0.001) for the LGMCP, 42.0 versus 12.4 (p = 0.02) for the HGMCP, and 15.4 versus 8.1 months (p = 0.61) for the HGMCP-S patients, respectively.

CONCLUSIONS

Selected low- and high-grade appendiceal cancer patients with MCP recurrence able to undergo iterative CRS/HIPEC procedures showed favorable outcomes and such patients should be considered for surgery when feasible. This survival benefit with iCRS/HIPEC is not evidenced in recurrent MCP with signet ring cell morphology.

Outcomes Following Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy with and without Diaphragmatic Resection in Patients with Peritoneal Metastases

BACKGROUND

Diaphragmatic resection (DR) is often required during cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) to achieve complete cytoreduction (CC). While CC provides the best survival, requiring a DR may indicate unfavorable tumor biology. We assessed how DR during CRS/HIPEC affects outcomes.

METHODS

A retrospective cohort study was conducted using a prospective single-center database from October 1994-May 2020. Peritoneal surface malignancy patients who underwent CRS/HIPEC with CC-0/1/2 were assigned to DR and NoDR groups. Survival was measured using the Kaplan-Meier method. Subgroup analysis was performed for patients with peritoneal cancer index (PCI) ≥ 20 to eliminate confounding of more extensive disease in DR.

RESULTS

Of 824 CRS/HIPECs, 774 were included: 134 DR and 640 NoDR. PCI was significantly higher in DR: 29 versus 21, p < 0.001. CC-0/1 rate was 89% in DR and 95% in NoDR (p = 0.003). Neither 100-day morbidity nor mortality differed between the groups (p = 0.355 and p = 1.000). Median follow-up was 64 months. Median overall survival (OS) was significantly lower in DR (32 vs. 96 months, p < 0.001). Subgroup analysis by tumor type in patients with PCI ≥ 20 showed significantly shorter OS in DR than NoDR in appendiceal (40 vs. 196 months, p < 0.001) and colorectal (14 vs. 23 months, p = 0.003), but not in ovarian tumors (32 vs. 42 months, p = 0.893), whereas median PCI did not differ among subgroups.

CONCLUSIONS

DR during CRS/HIPEC does not increase morbidity and mortality. It is associated with worse survival in appendiceal and colorectal tumors, even after adjusting for tumor burden but does not appear to impact ovarian cancer survival.

Cytoreductive Surgery with Hyperthermic Intrathoracic Chemotherapy for Patients with Intrapleural Dissemination of Peritoneal Surface Malignancies

BACKGROUND

Peritoneal surface malignancies (PSM) can disseminate into the pleural cavity, increasing morbidity and mortality. While cytoreductive surgery with hyperthermic intraperitoneal chemoperfusion (CRS/HIPEC) improves outcomes for PSM with intra-abdominal spread, the optimal approach for patients with pleural dissemination from PSM remains unclear. It seems reasonable to apply peritoneal carcinomatosis management principles to patients with pleural lesions using CRS and hyperthermic intrathoracic chemotherapy (HITHOC).

METHODS

We conducted a descriptive study to evaluate outcomes of PSM patients who underwent CRS/HITHOC for pleural dissemination using a high-volume PSM center's prospective database from October 1994-June 2020. CRS/HITHOC was performed via either diaphragmatic window during CRS/HIPEC (CRS/HIPEC+HITHOC) or thoracotomy as a separate procedure (CRS/HITHOC).

RESULTS

Of 852 completed CRS/HIPECs, 18 HITHOCs in 15 patients were identified: 10 CRS/HIPEC+HITHOCs, and 8 CRS/HITHOCs. CRS/HIPEC+HITHOC primary tumors included: 4 appendix, 4 ovary, 1 colon, and 1 unknown. All (n = 8) CRS/HITHOC patients had recurrent appendiceal neoplasms. Complete cytoreduction was achieved in 90% of CRS/HIPEC+HITHOCs and 75% of CRS/HITHOCs. Major complications occurred in 20% of CRS/HIPEC+HITHOCs and 13% of CRS/HITHOCs with no 30-day mortality in either group. After median follow-up of 22 months, overall survival at 1, 3, and 5 years was 93.3%, 67.9%, and 67.9%, while 1-, 3-, and 5-year progression-free survival was 70.9%, 20.3%, and 20.3%. Intrapleural recurrence occurred in 1 CRS/HIPEC+HITHOC and 2 CRS/HITHOC patients.

CONCLUSIONS

CRS/HITHOC performed via diaphragm or thoracotomy at high-volume centers is a safe option for PSM with pleural dissemination. Further comparative studies with longer follow-up are needed to evaluate survival by tumor type.

Delayed genital necrosis after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy with Mitomycin-C

INTRODUCTION

Genital necrosis (GN) is a rare complication of cytoreductive surgery with hyperthermic intraoperative chemotherapy (CRS/HIPEC) which can be confused with necrotizing fasciitis. We present an analysis of GN after CRS/HIPEC to define its natural history.

METHODS

We identified patients with GN after CRS/HIPEC at two peritoneal surface malignancy institutions. Patient demographic, surgical, and postoperative data were extracted from prospective databases.

RESULTS

Of 1597 CRS/HIPECs performed, 13 patients (0.8%) had GN. The median age was 57 years (IQR: 49-64) and 77% (n = 10) were male. Mitomycin-C was the perfusion agent in all cases of GN (100%). The median time to GN onset after CRS/HIPEC was 64 days (IQR: 60-108) and 2 (15%) patients were receiving systemic chemotherapy at the time of GN onset. Symptoms included severe pain (100%), edema (100%), labial or scrotal skin ulceration (92%), signs of infection (39%), and fever (15%). Seven (54%) patients had thrombocytosis >400 ∗10⁹/L, whereas coagulation tests were within normal reference range in 100% cases. All patients initially underwent conservative treatment, with antibiotic therapy administered in 62% (n = 8). Surgical debridement was performed in 9 (70%) cases with median time after GN onset of 57 (IQR: 8-180).

CONCLUSION

GN is a debilitating complication after CRS/HIPEC with delayed onset and a protracted clinical course. Optimal treatment results could be achieved with initial conservative management until complete lesion demarcation followed by surgical debridement. The pathophysiology of GN is unclear, and we call for other researchers attention to better understand the complication and prevention.

Surgical and oncological outcomes after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy at a nonacademic center: 25-year experience

BACKGROUND

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is predominantly performed and studied in academic centers. While developing CRS/HIPEC programs in nonacademic hospitals can increase accessibility, its safety and oncological efficacy remains unclear. We evaluated CRS/HIPEC outcomes in a nonacademic setting.

METHODS

A single-center descriptive study was conducted using a prospective database. Data of all CRS/HIPEC attempts in peritoneal surface malignancies (PSM) patients from October 1994 to November 2019 were extracted. Surgical and survival outcomes were measured. Center experience was assessed by quartiles of cases.

RESULTS

Overall, 856 patients underwent 948 CRS/HIPEC attempts: 788 (83%) completed CRS/HIPECs, 144 (15%) aborted HIPECs, and 16 (2%) complete cytoreductions (CC-0/1) without chemoperfusion. For completed CRS/HIPECs, median peritoneal cancer index was 24 (interquartile range: 10-33) and CC-0/1 rate was 88%. Major complications occurred in 23.5% with 30- and 100-day mortality of 1.0% and 2.3%, respectively. Median overall survival was 68 months (95% confidence interval [CI]: 50-86). Median progression-free survival was 37 months (95%CI: 28-46). Incomplete cytoreduction and major complication rates decreased over time, while mortality remained low and constant.

CONCLUSIONS

CRS/HIPEC at a nonacademic center with advanced surgical and auxiliary services is a safe option to treat PSM with favorable surgical and oncological outcomes.

Pelvic Anastomosis Without Protective Ileostomy is Safe in Patients Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

During cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC), surgeons are reluctant to perform unprotected pelvic anastomosis despite lack of supporting data. We analyzed pelvic anastomosis outcomes and factors that influence ostomy creation in CRS/HIPEC patients.

METHODS

A single-center, descriptive study of patients with rectal resection during CRS/HIPEC was conducted using a prospective database. Surgical variables were reviewed. Multinomial logistic regression of outcomes (end or protective ostomy) was performed with pre- and intraoperative factors as predictors.

RESULTS

Overall, 274 of 789 CRS/HIPEC patients underwent rectal resection, including 243 (89%) with pelvic anastomosis [232 (85%) without ostomy, 11 (4%) with protective ileostomy] and 31 (11%) with no anastomosis [16 (6%) with end colostomy, 15 (5%) with end ileostomy]. The median age was 57 and 29% (79) were male. Of 243 pelvic anastomosis patients, 3 (1.2%) had rectal anastomotic leaks, including 1 with a protective ileostomy. Other anastomotic leaks occurred in 3.6%. Overall, 13% had Clavien-Dindo complications ≥ IIIB and the readmission rate was 30%. Mortality at 30 days and 100 days was 0.4% and 2.2%, respectively. Male gender and primary rectal cancer were associated with protective ileostomy [odds ratio (OR) = 7.01, 95% CI: 1.6-31.5, p = 0.011, and OR = 16.4, 95% CI: 3-88.4, p = 0.001, respectively). Male gender and prior pelvic surgery were associated with end colostomy (OR = 13.9, 95% CI: 3.7-53, p < 0.0001, and OR = 17.2, 95% CI: 3.8-78.6, p < 0.0001).

CONCLUSIONS

Pelvic bowel reconstruction without protective or end ostomy during CRS/HIPEC is safe. Protective ileostomy is associated with male gender and primary rectal cancer. End colostomy is associated with male gender and prior pelvic surgery.

Impact of Mucin Cellularity and Distribution on Survival in Newly Diagnosed Patients with Low-Grade Appendiceal Mucinous Neoplasm Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Low-grade appendiceal mucinous neoplasms (LAMN) are tumors that frequently present with peritoneal spread of either acellular mucin (AM) or cellular mucin (CM). We aim to determine how mucin types and distribution affect survival. PATIENTS AND METHODS: A retrospective cohort study was conducted using a prospective database. Newly diagnosed LAMN patients with AM versus CM treated with cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) were compared. Postoperative pathology reports were reviewed to assess each involved abdominal zone. Survival was analyzed using the Kaplan-Meier method.

RESULTS

Of 121 identified patients, 50 (41%) had peritoneal lesions with AM and 71 (59%) with CM. Peritoneal cancer index was lower in AM versus CM (mean: 19 ± 13 vs 28 ± 10, p = 0.004), but complete cytoreduction (CC) rates were similar (98% vs 96%, p = 0.642). The 5-year progression-free survival (PFS) was higher in AM versus CM (96% vs 69.8%, p = 0.002). CM patients had zones with both types of lesions: with and without cells. The CM subgroup analysis showed significant differences in 5-year progression-free survival (PFS) among patients with 1-3, 4-7, and 8-10 zones with cells (95.2%, 68.4%, and 35.7%, respectively, p < 0.001), but PFS was not affected by the number of zones with any lesion type. There was no difference in overall survival (OS) between groups.

CONCLUSIONS

Despite comparable CC rates after CRS/HIPEC, CM patients have shorter PFS than AM patients. In CM patients, more zones with cells, but not the total number of involved zones, negatively impact PFS. Mucin type does not impact OS. It is important to assess and report mucin cellularity in LAMN specimens.

Soft-Tissue Myoepithelioma of the Retroperitoneal Space Mimicking a Pancreatic Tumor: A Case Report and Literature Review

Soft-tissue myoepithelioma (STM) is an extremely rare benign tumor with predominant occurrence in head, neck, pelvic girdle and limbs. These tumors lack specific clinical and morphological features and can easily be confused with more common neoplasms. It may lead to incorrect diagnosis and management. Here, we present a clinical case of a young man with retroperitoneal STM which simulated a pancreatic tumor and required a distal pancreatectomy. Performed literature review highlights current data about clinical, morphologic, immunohistochemical and genetic evaluation, treatment and prognosis of STM.

A Rare Case of Metastatic Heterogeneous Poorly Differentiated Neuroendocrine Carcinoma of Ileum: A Case Report and Literature Review

Neuroendocrine neoplasms (NENs) represent a diverse group of tumors arising from neuroendocrine cells. Current World Health Organization (WHO) classification is based on tumor differentiation and grade defined by mitotic rate and/or Ki-67 index to determine prognosis and treatment options. However, some NENs do not meet WHO pathology criteria due to morphologic heterogeneity and this leads to management challenges. WHO defines poorly differentiated NENs of the gastrointestinal tract as having morphologically large or small cell features with marked elevation of Ki-67. We present a unique clinical case that does not fit either growth pattern and also has heterogeneity with a well-differentiated component. This case report and literature review highlights the current limitations of the WHO classification of small bowel NENs and the subsequent challenges in management decisions for the patients.