Diminishing calcifications as a potential predictor of pancreatic ductal adenocarcinoma arising in association with IPMN in patients with chronic pancreatitis.

Chronic pancreatitis (CP) is a progressive benign fibroinflammatory condition involving repeated episodes of pancreatic inflammation, which lead to fibrotic tissue replacement and subsequent pancreatic insufficiency. A lifetime risk of developing pancreatic ductal adenocarcinoma (PDAC) in patients with chronic pancreatitis is reported to be 1.5%-4%. However, diagnosis of PDAC in patients with CP can be challenging, in part due to overlapping imaging features. In rare instances, pancreatic parenchymal calcifications that are typically associated with chronic pancreatitis may diminish in the case of a developing PDAC. In this article, we present a patient with chronic pancreatitis in whom calcifications decreased at the time of pancreatic ductal adenocarcinoma diagnosis, as compared to prior CT imaging. The unique imaging features of "diminishing calcifications" associated with a hypoattenuating lesion can potentially be a useful sign of pancreatic ductal adenocarcinoma and may aid in early diagnosis and prompt treatment intervention.

Radiomics machine learning algorithm facilitates detection of small pancreatic neuroendocrine tumors on CT.

PURPOSE: The purpose of this study was to develop a radiomics-based algorithm to identify small pancreatic neuroendocrine tumors (PanNETs) on CT and evaluate its robustness across manual and automated segmentations, exploring the feasibility of automated screening. MATERIALS AND METHODS: Patients with pathologically confirmed T1 stage PanNETs and healthy controls undergoing dual-phase CT imaging were retrospectively identified. Manual segmentation of pancreas and tumors was performed, then automated pancreatic segmentations were generated using a pretrained neural network. A total of 1223 radiomics features were independently extracted from both segmentation volumes, in the arterial and venous phases separately. Ten final features were selected to train classifiers to identify PanNETs and controls. The cohort was divided into training and testing sets, and performance of classifiers was assessed using area under the receiver operator characteristic curve (AUC), specificity and sensitivity, and compared against two radiologists blinded to the diagnoses. RESULTS: A total of 135 patients with 142 PanNETs, and 135 healthy controls were included. There were 168 women and 102 men, with a mean age of 55.4 ± 11.6 (standard deviation) years (range: 20-85 years). Median PanNET size was 1.3 cm (Q1, 1.0; Q3, 1.5; range: 0.5-1.9). The arterial phase LightGBM model achieved the best performance in the test set, with 90 % sensitivity (95 % confidence interval [CI]: 80-98), 76 % specificity (95 % CI: 62-88) and an AUC of 0.87 (95 % CI: 0.79-0.94). Using features from the automated segmentations, this model achieved an AUC of 0.86 (95 % CI: 0.79-0.93). In comparison, the two radiologists achieved a mean 50 % sensitivity and 100 % specificity using arterial phase CT images. CONCLUSION: Radiomics features identify small PanNETs, with stable performance when extracted using automated segmentations. These models demonstrate high sensitivity, complementing the high specificity of radiologists, and could serve as opportunistic screeners.

Instagram reels versus image posts in radiology education.

OBJECTIVE: In January 2016, we created an Instagram page for radiology education. Numerous publications in different fields have reported that Instagram "reels," introduced in 2020 as a short-form video feature, are more popular than image posts. These findings and our familiarity with Instagram prompted us to analyze our own data to better understand how image posts compared with reels when used in the context of radiology education. MATERIALS AND METHODS: For each post category, metric values were extracted from the Instagram platform and analyzed as continuous variables, reported as medians with interquartile ranges (IQR). Metrics were compared between image categories using the Kruskal-Wallis test, with resulting p-values adjusted for multiple comparisons using the Bonferroni correction. Corrected p-values of less than 0.05 were considered statistically significant. RESULTS: We included 128 images and 96 reels in the analysis. Images generally reached a larger audience, with a median of 18,745 [IQR: 13,478-27,243] impressions vs. 11,972 [IQR: 9,310.0-13,844.5] for reels (p < 0.01). Images also tended to be shared more frequently (median 19 vs. 20, p < 0.01), liked more often (median 480 vs. 296, p < 0.01), and saved more by users (median 138 vs. 84, p < 0.01) than reels, respectively. Both images and reels received a similar number of comments, with a median of 3 comments for both (p > 0.99). We also explored the performance differences of image post subcategories. Within images, our "You Make the Call!" (YMTC) questions (n = 23) displayed higher performance metrics across the board than the three other types of image posts combined (n = 105). When compared, the median number of impressions for YMTC images was 36,735 [IQR: 31,343-40,742] vs. 15,992 [IQR:12,774-21,873] for other types of images (p < 0.01). YMTC images were shared more often (median 25 vs. 17, p < 0.01), received more likes (median 809 vs. 445, p < 0.01) and saves (median 206 vs. 119, p < 0.01) than non-YMTC images, respectively. User engagement showed slightly different trends with YMTC reels being the most liked, while quiz reels receiving the most comments and talking clips being the most saved. CONCLUSION: Our findings on the use of Instagram in radiology education suggest that static images perform much better than reels. Consequently, we recommend to radiology educators seeking to establish an Instagram presence that using static image posts is an appropriate approach for reaching a radiology audience, particularly with image posts that engage an audience with participatory opportunities such as answering quiz-like questions aimed at making a diagnosis.

Quality of Life After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS/HIPEC): Cancer Survivors' Perspective Through In-Depth Interviews.

BACKGROUND: CRS/HIPEC patients face unique quality of life (QoL) challenges due to advanced disease (peritoneal carcinomatosis), the extent of procedure, and risk for long-term complications. Standard QoL questionnaires are generic, focusing on tumor type and standard treatments, and likely do not capture this select population's full experience, suggesting the need for tailored instruments. We aimed to characterize the QoL challenges faced by CRS/HIPEC cancer survivors and determine whether these were captured by a standard QoL questionnaire. PATIENTS AND METHODS: An anonymous, semi-structured individual interview was conducted with CRS/HIPEC patients addressing their experience at diagnosis, challenges related to CRS/HIPEC, and access to CRS/HIPEC information. Verbatim transcripts were interpreted using thematic analysis. Code and theme identification was inductive. Questions addressing common themes that were not encompassed by a standard QoL questionnaire were developed. RESULTS: We interviewed eight patients. Median age was 55 (range 30-71) years and 75% (n = 6) were women. Primary tumor sites included appendix (n = 4), ovarian (n = 3), and peritoneal mesothelioma (n = 1). Median time from CRS/HIPEC was 40.1 (range 3.1-216.3) months. Overall, 133 codes were identified and categorized into 9 themes. The most recurring were physical symptoms after CRS/HIPEC (specifically gastrointestinal symptoms), adjusting to survivorship, mental health, expectations from CRS/HIPEC, and access to care. A total of 22 questions that did not overlap with a standardized QoL questionnaire were developed. CONCLUSIONS: There is an unmet need to understand the unique QoL challenges CRS/HIPEC patients encounter. Patient-centered QoL questionnaires based on CRS/HIPEC patient experiences can capture these unique challenges and help guide future studies and care.

Early detection of pancreatic cancer in the era of precision medicine.

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related mortality and it is often diagnosed at advanced stages due to non-specific clinical presentation. Disease detection at localized disease stage followed by surgical resection remains the only potentially curative treatment. In this era of precision medicine, a multifaceted approach to early detection of PDAC includes targeted screening in high-risk populations, serum biomarkers and "liquid biopsies", and artificial intelligence augmented tumor detection from radiologic examinations. In this review, we will review these emerging techniques in the early detection of PDAC.

Peritoneal metastases from rare ovarian cancer treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC).

Objectives: There are limited treatment options and no consensus on the management of advanced rare ovarian malignancies. Rare ovarian malignancies can present with peritoneal metastases (PM), featuring a similar presentation to more common ovarian subtypes. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is an effective treatment for PM of non-gynecologic origin and, recently, epithelial ovarian cancer. We evaluated the feasibility of CRS/HIPEC in the management of PM from rare ovarian malignancies and report postoperative outcomes on these patients. Methods: A retrospective review of a single center, prospective database (1994-2021) was performed to identify patients with rare ovarian malignancies treated with CRS/HIPEC. Clavien-Dindo 90-day morbidity/mortality and Kaplan-Meier overall (OS) and progression-free survival (PFS) were analyzed. Results: Of 44 patients identified, 28 underwent CRS/HIPEC. Six were aborted due to extensive disease. Histologic subtypes included: clear cell (5/28, 17.9 %), endometrioid (5/28, 17.9 %), granulosa cell (3/28, 10.7 %), low-grade serous (6/28, 21.4 %), mesonephric (1/28, 3.6 %), mucinous (6/28, 21.4 %), and small cell (2/28, 7.1 %) carcinomas. Eight (28.6 %) patients had primary and 20 (71.4 %) had recurrent disease. Median peritoneal cancer index (PCI) was 21 (IQR: 6-29). Complete cytoreduction (<2.5 mm residual disease) was achieved in 27/28 (96.4 %). Grade III/IV complications occurred in 9/28 (32.1 %) with one (3.6 %) mortality. After a median follow-up of 65.8 months, 20 patients were alive. Five-year OS and PFS were 68.5 and 52.6 %, respectively. Conclusions: In patients with PM from rare ovarian malignancies, CRS/HIPEC is feasible and has an acceptable safety profile. Longer follow-up and multicenter trials are needed.

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.

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.

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.

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.

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.

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.