Tumour Genome Characterization of a Rare Case of Pulmonary Enteric Adenocarcinoma and Prior Colon Adenocarcinoma

Pulmonary enteric adenocarcinoma (PEAC) is a rare variant of lung adenocarcinoma first described in the early 1990s in a lung tumour with overlapping lung and small intestine features. It is a rare tumour with fewer than 300 cases described in the published literature and was only formally classified in 2011. Given these characteristics the diagnosis is challenging, but even more so in a patient with prior gastrointestinal malignancy. A 68-year-old Caucasian female presented with a cough and was found to have a right upper lobe mass. Her history was significant for a pT3N1 colon adenocarcinoma. The resected lung tumour showed invasive lung adenocarcinoma but also features of colorectal origin. Immuno-stains were strongly and diffusely positive for lung and enteric markers. Multi-region, whole-exome sequencing of the mass and archival tissue from the prior colorectal cancer showed distinct genomic signatures with higher mutational burden in the PEAC and very minimal overlap in mutations between the two tumours. This case highlights the challenge of diagnosing rare lung tumours, but more specifically PEAC in a patient with prior gastro-intestinal cancer. Our use of multi-region, next-generation sequencing revealed distinct genomic signatures between the two tumours further supporting our diagnosis, and evidence of PEAC intra-tumour heterogeneity.

RESULTS OF HYPERTHERMIC INTRAPERITONEAL CHEMOTHERAPY AND CYTOREDUCTIVE SURGERY FOR PERITONEAL CARCINOMATOSIS OF COLORECTAL ORIGIN

INTRODUCTION Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is supported by clinical practice and published series as a fundamental treatment for increasing survival of selected patients with colorectal peritoneal carcinomatosis. The results were evaluated since having implemented a peritoneal oncological surgery program five years ago. MATERIAL AND METHODS Descriptive analysis was conducted to patients who had been diagnosed with peritoneal carcinomatosis from May 2014 to December 2020. 36 out of 100 patients who had undergone surgery were included in the CRS and HIPEC assessment and 6 patients without HIPEC, were excluded. RESULTS The mean preoperative PCI was 7.81±6.61 accomplishing complete cytoreduction CC 0-CC-1 in the 36 cases. An average of 1.86±1.22 peritonectomies were performed. Among procedures, complete pelviperitonectomy (11 patients) and liver metastasis resection (6 patients) should be noticed. Complications were presented in 16 patients (8 patients over Clavien Dindo>III) and 6 required reinterventions due to hematoma (2) or anastomotic leak (2) mostly. The 4-year overall survival is 76.2% and the disease-free interval is 34 months within an average follow-up of 23 months. CONCLUSIONS The overall survival and disease-free interval rates are above the standards. Currently, peritoneal carcinomatosis might be considered a curative disease. The multidisciplinary assessment allows selecting patients who will benefit from surgery.

Diagnostic Pitfalls Related to Morular Metaplasia in Endometrioid Carcinoma: An Underestimated Issue

Here, we present a case that highlights the crucial pitfalls related to the presence of morular metaplasia (MM) in endometrioid carcinoma, which are insufficiently recognized in the routine pathology practice. A 45-year-old woman underwent hysterectomy with rectosigmoidectomy due to a 11-cm mass involving uterus, right ovary, and rectosigmoid colon. Histologically, the lesion appeared as a predominantly solid carcinoma with a minor glandular component. Results of the first immunohistochemical analysis suggested a colorectal origin (PAX8-, CK7-, WT1-, hormone receptors-, and CDX2+ in the absence of mucinous features). Subsequent immunohistochemistry (nuclear β-catenin+, CD10+, and low ki67 in the solid areas) supported a diagnosis of endometrioid carcinoma with diffuse MM. This case remarks that morphological and immunohistochemical features of MM may conceal the glandular architecture and the typical immunophenotype of endometrioid carcinomas. Acknowledging the diagnostic issues related to MM appears crucial to avoid misdiagnosis and inappropriate patient management.

Morbidity associated with the use of oxaliplatin versus mitomycin C in hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis of colorectal or appendiceal origin: a multi-institutional comparative study

Background: The raw costs of mitomycin C (MMC) and oxaliplatin for hyperthermic intraperitoneal chemotherapy (HIPEC) differ substantially. We sought to compare the morbidity and toxicity profiles associated with the use of oxaliplatin and MMC in patients undergoing cytoreductive surgery (CRS) and HIPEC for peritoneal carcinomatosis (PC) of colorectal or appendiceal origin, to evaluate whether the costeffectiveness of these 2 agents should dictate drug choice. Methods: We conducted a retrospective multi-institutional study of all patients with PC of colorectal or appendiceal origin treated with CRS-HIPEC using MMC or oxaliplatin from 2010 to 2015. Demographic, perioperative, morbidity, toxicity and cost data were compared between the 2 treatment groups and between cancer-origin subgroups. Results: Forty-two patients treated with MMC and 76 treated with oxaliplatin were included in the study. Baseline demographic and tumour characteristics were comparable in the 2 groups, except that the patients treated with MMC had higher Charlson Comorbidity Index scores. The MMC group had a higher rate of cancer of colorectal origin (76.2% v. 57.9%, p = 0.047) and longer operative times (553 v. 320 min, p < 0.001). In the subgroup of patients whose cancer was of colorectal origin, patients treated with MMC had a higher transfusion rate (50.0% v. 28.6%, p = 0.023) and lower postoperative baseline hemoglobin level (100 v. 119 g/L, p = 0.002) than those treated with oxaliplatin. There was no difference in hematologic toxicity scores after controlling for postoperative anemia. There was no difference in the rates of major complications and 90-day mortality. However, MMC was less costly than oxaliplatin ($724 v. $8928). Conclusion: MMC and oxaliplatin are both suitable agents for HIPEC and are associated with comparable morbidity and toxicity profiles, regardless of cancer origin. Thus, we propose that cost-effectiveness should ultimately dictate drug selection.

Intraperitoneal collagenase as a novel therapeutic approach in an experimental model of colorectal peritoneal carcinomatosis

The usefulness of local collagenase in therapeutic approaches to solid tumors has been tested recently. In this study, we evaluate the safety and efficacy of intraperitoneal collagenase associated or not to mitomycin for treatment of colorectal peritoneal metastases in an experimental rat model. Using a fixed-dose procedure, we found that a dose of collagenase of 37 IU/mL administered for 15 min with a hyperthermia pump at 37.5 °C, both in isolation or associated to sequential treatment with intraperitoneal mitomycin, led to a macroscopic decrease in tumor volume as evaluated by the modified peritoneal cancer index (mPCI). Concerning the safety of the procedure, the animals showed no physiological or behavioral disorders during 8 weeks of follow-up. Local treatment for peritoneal metastases of colorectal origin with intraperitoneal collagenase has proved safe and effective in an experimental murine model. Therefore, the stroma-first approach by enzymatic breakdown of collagen from the tumor's extracellular matrix provides a new therapeutic target for colorectal peritoneal metastases.

Severe hypercalcemia caused by parathyroid hormone in a rectal cancer metastasis: a case report

Background Hypercalcemia of malignancy is relatively common in several cancers. However, in colorectal cancer, paraneoplastic phenomena that cause hypercalcemia is uncommon. In the few cases that are reported, secretion of parathyroid hormone-related peptide mediates the effect. We describe the first case of severe hypercalcemia mediated by intact parathyroid hormone secretion from a bone metastasis of colorectal origin. This was a diagnostic and therapeutic challenge. Case presentation A 68-year-old male treated for rectal adenocarcinoma 10 years earlier developed a bone metastasis. After initial treatment of the metastasis with surgery and irradiation, he developed a relapse with severe hypercalcemia and corresponding elevated parathyroid hormone levels. The workup showed no signs of parathyroid adenomas, but the metastasis produced intact parathyroid hormone. The hypercalcemia was successfully treated by irradiation and osteoclast inhibitor, and the patient received chemotherapy. Survival was 24 months from the onset of hypercalcemia. Conclusions Proper diagnosis of the uncommon endocrine disturbance allowed targeted therapy and avoidance of neck exploration for wrongly suspecting primary hyperparathyroidism. Intact parathyroid hormone should be measured in cases of malignant hypercalcemia.