Correlation of tumor microenvironment from biopsy and resection specimens in untreated colorectal cancer patients: a surprising lack of agreement.

BACKGROUND: Colorectal cancer (CRC) tumor microenvironment (TME) characteristics, such as tumor infiltrating lymphocyte (TIL) densities and PD-L1 status, are predictive of recurrence, disease-free survival, and overall survival. In many malignancies, TME characteristics are also predictive of response to immunotherapy. As window of opportunity studies using neoadjuvant immunotherapy become more common and treatment guidelines incorporate TME features, accurate assessment of the pre-treatment TME using the biopsy specimen is critical. However, no study has thoroughly evaluated the correlation between the TMEs of the biopsy and resection specimens. METHODS: We conducted a retrospective analysis of patients with stage I-III CRC with matched biopsy and resection specimens. CD3+, CD4+, CD8+, and FoxP3+ lymphocyte populations at the center of tumor (CT) and invasive margin (IM) and tumor PD-L1 status in the biopsy and resection specimens were evaluated. TIL populations were compared using Mann-Whitney U tests or Student's t tests and correlated using Pearson r. RESULTS: CD3+ and CD4+ densities were significantly higher in the CT of the biopsy relative to the resection specimen Comparing biopsy and resection specimens, no TIL population at either the CT or IM had a correlation coefficient > 0.5. Determining PD-L1 status based on biopsy tissue resulted in a sensitivity of 37.1%, specificity of 81.4%, and accuracy of 61.5%. CONCLUSIONS: These findings demonstrate significant discordance between the TME of the biopsy and resection specimens. Caution should be used when basing treatment decisions on pre-treatment endoscopic biopsy findings and when interpreting changes in the TME between pre-treatment biopsy and resection specimens after neoadjuvant therapy.

Extraovarian sex cord tumor with annular tubules discovered arising from a leiomyoma.

BACKGROUND: Sex cord tumors with annular tubules (SCTAT) are a rare (2%) subtype of ovarian sex cord-stromal tumor. SCTATs are usually cured at time of diagnosis by surgical resection with an oophorectomy. SCTATs have a 100%(disease related) five-year survival. One third of SCTAT tumors are associated with Peutz-Jeghers syndrome. Literature review discovered only two published cases of extra-ovarian SCTAT. Due to the rarity there is no standard treatment for extraovarian SCTATs. CASE: A 39-year-old para-1 female with a symptomatic fibroid uterus, heavy menstrual bleeding, and a history of a uterine myomectomy, underwent an elective total abdominal hysterectomy. Intraoperative findings showed a 7.5 cm retroperitoneal mass adhered between the uterus and the right pelvic sidewall that on frozen section was found to be a degenerating leiomyoma. Final pathology demonstrated a 2 mm focus of incidental SCTAT adjacent to the serosal surface of the leiomyoma. The SCTAT was not associated with ectopic ovarian tissue or endometriosis. The patient's ovaries were normal on direct intraoperative examination, preoperative ultrasound and MRI. Six month postoperative surveillance ultrasound also demonstrated normal premenopausal ovaries. CONCLUSION: This is the first extraovarian SCTAT in the published literature arising from a leiomyoma. Our patient had no family history and displayed no syndromic features for Peutz-Jeghers Syndrome. Ultimately, she declined genetic testing. The lack of evidence of ovarian involvement on both imaging and on intraoperative examination made localization to either ovary impossible. The patient is currently being managed with surveillance since the morbidity associated with bilateral oophorectomy in the 4th decade of life exceeds the theoretical risk of SCTAT.

Mature Cystic Teratoma: AIRP Best Cases in Radiologic-Pathologic Correlation.

Editor's Note.-RadioGraphics continues to publish radiologic-pathologic case material selected from the American Institute for Radiologic Pathology (AIRP) "best case" presentations. The AIRP conducts a 4-week Radiologic Pathology Correlation Course, which is offered five times per year. On the penultimate day of the course, the best case presentation is held at the American Film Institute Silver Theater and Cultural Center in Silver Spring, Md. The AIRP faculty identifies the best cases, from each organ system, brought by the resident attendees. One or more of the best cases from each of the five courses are then solicited for publication in RadioGraphics. These cases emphasize the importance of radiologic-pathologic correlation in the imaging evaluation and diagnosis of diseases encountered at the institute and its predecessor, the Armed Forces Institute of Pathology (AFIP).