TTF1 Expression in Pulmonary Metastatic Rectal Adenocarcinoma

A Challenging Task: Identifying Patients with Cancer of Unknown Primary (CUP) According to ESMO Guidelines: The CUPISCO Trial Experience

BACKGROUND

CUPISCO is an ongoing randomized phase II trial (NCT03498521) comparing molecularly guided therapy versus platinum-based chemotherapy in patients newly diagnosed with "unfavorable" cancer of unknown primary (CUP).

MATERIALS AND METHODS

Patients with an unfavorable CUP diagnosis, as defined by the European Society of Medical Oncology (ESMO), and available cancer tissue for molecular sequencing are generally eligible. Potential patients with CUP entering screening undergo a review involving reference histopathology and clinical work-up by a central eligibility review team (ERT). Patients with "favorable" CUP, a strongly suspected primary site of origin, lack of tissue, or unmet inclusion criteria are excluded.

RESULTS

As of April 30, 2020, 628 patients had entered screening and 346 (55.1%) were screen failed. Screen fails were due to technical reasons (n = 89), failure to meet inclusion and exclusion criteria not directly related to CUP diagnosis (n = 89), and other reasons (n = 33). A total of 124 (35.8%) patients were excluded because unfavorable adeno- or poorly differentiated CUP could not be confirmed by the ERT. These cases were classified into three groups ineligible because of (a) histologic subtype, such as squamous and neuroendocrine, or favorable CUP; (b) evidence of a possible primary tumor; or (c) noncarcinoma histology.

CONCLUSION

Experience with CUPISCO has highlighted challenges with standardized screening in an international clinical trial and the difficulties in diagnosing unfavorable CUP. Reconfirmation of unfavorable CUP by an ERT in a clinical trial can result in many reasons for screen failures. By sharing this experience, we aim to foster understanding of diagnostic challenges and improve diagnostic pathology and clinical CUP algorithms.

IMPLICATIONS FOR PRACTICE

A high unmet need exists for improved treatment of cancer of unknown primary (CUP); however, study in a trial setting is faced with the significant challenge of definitively distinguishing CUP from other cancer types. This article reports the authors' experience of this challenge so far in the ongoing CUPISCO trial, which compares treatments guided by patients' unique genetic signatures versus standard chemotherapy. The data presented will aid future decision-making regarding diagnosing true CUP cases; this will have far-reaching implications in the design, execution, and interpretation of not only CUPISCO but also future clinical studies aiming to find much-needed treatment strategies.

Identifying Cattle Breed-Specific Partner Choice of Transcription Factors during the African Trypanosomiasis Disease Progression Using Bioinformatics Analysis

African Animal Trypanosomiasis (AAT) is a disease caused by pathogenic trypanosomes which affects millions of livestock every year causing huge economic losses in agricultural production especially in sub-Saharan Africa. The disease is spread by the tsetse fly which carries the parasite in its saliva. During the disease progression, the cattle are prominently subjected to anaemia, weight loss, intermittent fever, chills, neuronal degeneration, congestive heart failure, and finally death. According to their different genetic programs governing the level of tolerance to AAT, cattle breeds are classified as either resistant or susceptible. In this study, we focus on the cattle breeds N’Dama and Boran which are known to be resistant and susceptible to trypanosomiasis, respectively. Despite the rich literature on both breeds, the gene regulatory mechanisms of the underlying biological processes for their resistance and susceptibility have not been extensively studied. To address the limited knowledge about the tissue-specific transcription factor (TF) cooperations associated with trypanosomiasis, we investigated gene expression data from these cattle breeds computationally. Consequently, we identified significant cooperative TF pairs (especially DBP−PPARA and DBP−THAP1 in N’Dama and DBP−PAX8 in Boran liver tissue) which could help understand the underlying AAT tolerance/susceptibility mechanism in both cattle breeds.

Metachronous Pancreatic Metastasis from Rectal Cancer that Masqueraded as a Primary Pancreatic Cancer: A Rare and Difficult-to-Diagnose Metastatic Tumor in the Pancreas

BACKGROUND Pancreatic metastasis from colorectal cancer is rare and can masquerade as primary pancreatic cancer. CASE REPORT A 70-year-old male was diagnosed with advanced rectal cancer with multiple liver metastases. After neoadjuvant chemotherapy, he underwent radical surgery for the primary tumor and hepatectomy for multiple liver metastases. Adjuvant chemotherapies and additional surgeries were subsequently required for recurrences in the liver, lung, and lymph nodes. A diffuse hypovascular nodule in the pancreatic head and a solitary liver metastasis were detected 2.5 years after the initial surgery and he accordingly underwent further chemotherapy. However, the pancreatic tumor progressed, invading the pancreatic duct and biliary tract. Obstructive jaundice finally prompted discontinuation of chemotherapy and he underwent biliary drainage. His diffuse and hypovascular tumor was clinically and radiographically diagnosed as a primary pancreatic cancer. Pancreatic resection for the pancreatic tumor and hepatectomy for the liver metastasis were performed 4.2 years after the initial surgery, achieving radiographic and surgical curative resection. Pathological examination of the surgical specimen resulted in a definitive diagnosis of metachronous pancreatic metastasis from his primary rectal cancer. Despite further chemotherapy, his general condition worsened; however, he remains alive 5.4 years after the initial surgery, with best supportive care. CONCLUSIONS Pancreatic metastasis originating from rectal cancer can masquerade as primary pancreatic cancer clinically and radiologically. Multimodality treatment is mandatory for metastatic colorectal cancer. Aggressive surgeries for pancreatic metastasis should be considered if curative resection appears possible radiographically and/or intraoperatively.

Simultaneous expression of TTF1 and GATA3 in a lung biopsy sample: confusion in diagnostic pathology

BACKGROUND

In daily work, pathologists often use TTF1 and GATA3 in the differential diagnosis of primary lung adenocarcinoma (TTF1+ GATA3-) and metastatic bladder cancer (or breast cancer) (TTF1- GATA3+). However, we encountered a small lung biopsy sample of TTF1+ GATA3+ (clinically suggesting both lung and bladder occupancy), and the dyeing results caused us great confusion; thus, we intended to determine the expressions of TTF1 and GATA3 in lung and bladder cancer by expanding the sample.

METHODS

The study included a complete case report and the tissue microarrays including pulmonary squamous cell carcinomas (n = 55), lung adenocarcinomas (n = 47), high-grade (n = 68) and low-grade (n = 43) urothelial carcinomas of the bladder. TTF1 and GATA3 immunohistochemical staining were performed on the tissue microarrays, and the relevant literature was retrieved.

RESULTS

Our staining results on tissue microarrays showed that TTF1 was expressed in pulmonary adenocarcinomas (44/47, 93.6%), squamous cell carcinomas (1/55, 1.8%), low-grade (1/43, 2.3%) and high-grade (2/68, 2.9%) urothelial carcinomas; GATA3 was only expressed in urothelial carcinomas of the bladder (high-grade: 48/68, 70.6%; low-grade: 42/43, 97.7%). Our literature search results showed that TTF1 could be expressed in a very small number of bladder urothelial carcinomas, and GATA3 could be expressed in a few primary lung squamous cell carcinomas and a very small number of primary lung adenocarcinomas.

CONCLUSIONS

TTF1 and GATA3 are good markers in the differential diagnosis of primary non-small cell lung cancer (GATA3-) and metastatic urothelial carcinoma of the bladder (GATA3+). However, pathologists should pay attention to a few special cases: lung cancer may express GATA3, and urothelial carcinoma may express TTF1. In these cases, some additional immunohistochemical markers, such as napsin A and URO III, should be added to assist the diagnosis.