Peritoneal carcinomatosis (PC) and peritoneal tuberculosis (PTB) have similar clinical and radiologic imaging features, which make it very difficult to differentiate between the two entities clinically. Our aim was to determine if the CT textural parameters of omental lesions among patients with PC were different from those with PTB.
All patients who had undergone omental biopsy at our institution from January 2010 to December 2018 and had a tissue diagnosis of PC or PTB were eligible for inclusion. Patients who did not have a contrast-enhanced CT abdomen within one month of the omental biopsy were excluded. A region of interest (ROI) was manually drawn over omental lesions and radiomic features were extracted using open-source LIFEx software. Statistical analysis was performed to compare mean differences in CT texture parameters between the PC and PTB groups.
A total of 66 patients were included in the study of which 38 and 28 had PC and PTB, respectively. Omental lesions in patients with PC had higher mean radiodensity (mean difference: +32.4; p = 0.001), higher mean entropy (mean difference: +0.11; p < 0.001), and lower mean energy (mean difference: -0.024; p = 0.001) compared to those in PTB. Additionally, omental lesions in the PC group had lower gray-level co-occurrence matrix (GLCM) homogeneity (mean difference: -0.073; p < 0.001) and higher GLCM dissimilarity (mean difference: +0.480; p < 0.001) as compared to the PTB group.
CT texture parameters of omental lesions differed significantly between patients with PTB and those with PC, which may help clinicians in differentiating between the two entities.

Existing literature about peritoneal tuberculosis (TBP) is relatively insufficient. The majority of reports are from a single center and do not assess predictive factors for mortality. In this international study, we investigated the clinicopathological characteristics of a large series of patients with TBP and determined the key features associated with mortality. TBP patients detected between 2010 and 2022 in 38 medical centers in 13 countries were included in this retrospective cohort. Participating physicians filled out an online questionnaire to report study data. In this study, 208 patients with TBP were included. Mean age of TBP cases was 41.4 ± 17.5 years. One hundred six patients (50.9%) were females. Nineteen patients (9.1%) had HIV infection, 45 (21.6%) had diabetes mellitus, 30 (14.4%) had chronic renal failure, 12 (5.7%) had cirrhosis, 7 (3.3%) had malignancy, and 21 (10.1%) had a history of immunosuppressive medication use. A total of 34 (16.3%) patients died and death was attributable to TBP in all cases. A pioneer mortality predicting model was established and HIV positivity, cirrhosis, abdominal pain, weakness, nausea and vomiting, ascites, isolation of Mycobacterium tuberculosis in peritoneal biopsy samples, TB relapse, advanced age, high serum creatinine and ALT levels, and decreased duration of isoniazid use were significantly related with mortality (p < 0.05). This is the first international study on TBP and is the largest case series to date. We suggest that using the mortality predicting model will allow early identification of high-risk patients likely to die of TBP.

It is still a challenge to make early differentiation of peritoneal tuberculosis (PTB) and peritoneal carcinomatosis (PC) clinically as well as on imaging and laboratory tests. We aimed to develop a model to differentiate PTB from PC based on clinical characteristics and primary CT signs.
This retrospective study included 88 PTB patients and 90 PC patients (training cohort: 68 PTB patients and 69 PC patients from Beijing Chest Hospital; testing cohort: 20 PTB patients and 21 PC patients from Beijing Shijitan Hospital). The images were analyzed for omental thickening, peritoneal thickening and enhancement, small bowel mesentery thickening, the volume and density of ascites, and enlarged lymph nodes (LN). Meaningful clinical characteristics and primary CT signs comprised the model. ROC curve was used to validate the capability of the model in the training and testing cohorts.
There were significant differences in the following aspects between the two groups: (1) age; (2) fever; (3) night sweat; (4) cake-like thickening of the omentum and omental rim (OR) sign; (5) irregular thickening of the peritoneum, peritoneal nodules, and scalloping sign; (6) large ascites; and (7) calcified and ring enhancement of LN. The AUC and F1 score of the model were 0.971 and 0.923 in the training cohort and 0.914 and 0.867 in the testing cohort.
The model has the potential to distinguish PTB from PC and thus has the potential to be a diagnostic tool.

UNASSIGNED: The sensitivity of single abdominal paracentesis for diagnosis of peritoneal carcinomatosis (PC) varies from 40-70%. We hypothesized that rolling-over the patient before paracentesis might improve the cytological yield.
UNASSIGNED: This was a single center pilot study with a randomized cross-over design. We compared the cytological yield of fluid obtained by roll-over technique (ROG) with standard paracentesis (SPG) in suspected PC. In the ROG group, patients were rolled side-to-side thrice, and the paracentesis was done within 1 minute. Each patient served as their own control, and the outcome assessor (cytopathologist) was blinded. The primary objective was to compare the tumor cell positivity between SPG and ROG groups.
UNASSIGNED: Of 71 patients, 62 were analyzed. Of 53 patients with malignancy-related ascites, 39 had PC. Most of the tumor cells were adenocarcinoma (30, 94%) with one patient each having suspicious cytology and one having lymphoma. The sensitivity for diagnosis of PC was (31/39) 79.49% in SPG group and (32/39) 82.05% in ROG group (p = 1.00). The cellularity was similar between both the groups (good cellularity in 58% of SPG and 60% of ROG, p = 1.00).
UNASSIGNED: Rollover paracentesis did not improve the cytological yield of abdominal paracentesis.
UNASSIGNED: CTRI/2020/06/025887 and NCT04232384.

The sensitivity of single abdominal paracentesis for diagnosis of peritoneal carcinomatosis in patients with malignant ascites is 40-70%. Tumor cells shed from the peritoneum settle preferentially in certain recesses of the peritoneum. We aim to compare the standard technique of abdominal paracentesis versus a rollover technique in a randomized crossover study to assess the cytological yield in patients suspected to have peritoneal carcinomatosis. Each patient will serve as their own control and the outcome assessor (cytopathologist) will be blinded to the method of paracentesis performed. The primary objective will be to compare the tumor cell positivity between the standard paracentesis group and the rollover group among enrolled patients. Clinical Trial registration: CTRI/2020/06/025887 and NCT04232384.
Lay abstract Existing methods of diagnosing cancer-related ascites are dependent on microscopic evaluation of fluid obtained from the ascites. However, this may not diagnose all such cases because the fluid may not contain many tumor cells. This may be due to the settling of tumor cells in certain inaccessible locations of the peritoneum (the lining of the abdominal cavity). This trial will look at whether rolling the patient from side to side could be helpful in increasing the chances of finding tumor cells in the ascites.

BACKGROUND: The duration of treatment of gastrointestinal tuberculosis continues to be a matter of debate. The World Health Organization advocates intermittent directly observed short-course therapy (DOTs), but there is a lack of data of its efficacy in abdominal tuberculosis. We therefore conducted a multicenter randomized controlled trial to compare 6 months and 9 months of antituberculosis therapy using DOTs.
METHODS: One hundred ninety-seven patients with abdominal tuberculosis (gastrointestinal, 154; peritoneal, 40; mixed, 3) were randomized to receive 6 months (n = 104) or 9 months (n = 93) of antituberculosis therapy using intermittent directly observed therapy. Patients were followed up 1 year after completion of treatment to assess recurrence. Patients were evaluated for primary endpoint (complete clinical response, partial response, and no response) and secondary endpoint (recurrence of the disease at the end of 1 year of follow-up).
RESULTS: Baseline characteristics were similar between the 2 randomized groups. There was no difference between the 6-month group and 9-month group in the complete clinical response rate on per-protocol analysis (91.5% vs 90.8%; P = .88) or intent-to-treat analysis (75% vs 75.8%; P = .89). Only 1 patient in the 9-month group and no patients in the 6-month group had recurrence of disease. Side effects occurred in 21 (21.3%) and 16 (18.2%) patients in the 6-month and 9-month groups, respectively.
CONCLUSIONS: There was no difference in efficacy of antituberculosis therapy delivered for either 6 months or 9 months in either gastrointestinal or peritoneal tuberculosis, confirming the efficacy of intermittent directly observed therapy.
BACKGROUND: NCT01124929.