The increasing incidence of cancer worldwide is multifactorial, attributable to population longevity, changing environmental and lifestyle factors, and increased surveillance. Thyroid cancer is a prime example for which intensified surveillance has resulted in an increasing incidence of early cancers with indolent behavior,^1,2 a phenomenon commonly described as cancer “overdiagnosis.”³ The increasing incidence is solely attributable to papillary thyroid carcinoma (PTC), a tumor named for its papillary growth pattern, although the defining diagnostic criteria are actually the nuclear features of neoplastic cells.⁴ Aside from the enhanced screening, another important factor contributing to this phenomenon is the increase in diagnosis of a variant of PTC known as the follicular variant of PTC (FVPTC).⁵

Tumor microenvironments (TMEs) influence cancer progression but are complex and often differ between patients. Considering that microenvironment variations may reveal rules governing intratumoral cellular programs and disease outcome, we focused on tumor-to-tumor variation to examine 52 head and neck squamous cell carcinomas. We found that macrophage polarity—defined by CXCL9 and SPP1 (CS) expression but not by conventional M1 and M2 markers—had a noticeably strong prognostic association. CS macrophage polarity also identified a highly coordinated network of either pro- or antitumor variables, which involved each tumor-associated cell type and was spatially organized. We extended these findings to other cancer indications. Overall, these results suggest that, despite their complexity, TMEs coordinate coherent responses that control human cancers and for which CS macrophage polarity is a relevant yet simple variable.

Renal cell carcinoma (RCC) occurs in 2% to 4% of patients with tuberous sclerosis complex (TSC). Previous reports have noted a variety of histologic appearances in these cancers, but the full spectrum of morphologic and molecular features has not been fully elucidated. We encountered 46 renal epithelial neoplasms from 19 TSC patients and analyzed their clinical, pathologic, and molecular features, enabling separation of these 46 tumors into 3 groups. The largest subset of tumors (n=24) had a distinct morphologic, immunologic, and molecular profile, including prominent papillary architecture and uniformly deficient succinate dehydrogenase subunit B (SDHB) expression prompting the novel term “TSC-associated papillary RCC (PRCC).” The second group (n=15) were morphologically similar to a hybrid oncocytic/chromophobe tumor (HOCT), whereas the last 7 renal epithelial neoplasms of group 3 remained unclassifiable. The TSC-associated PRCCs had prominent papillary architecture lined by clear cells with delicate eosinophilic cytoplasmic thread-like strands that occasionally appeared more prominent and aggregated to form eosinophilic globules. All 24 (100%) of these tumors were International Society of Urological Pathology (ISUP) nucleolar grade 2 or 3 with mostly basally located nuclei. Tumor cells from 17 of 24 TSC-associated PRCCs showed strong, diffuse labeling for carbonic anhydrase IX (100%), CK7 (94%), vimentin (88%), and CD10 (83%) and were uniformly negative for SDHB, TFE3, and AMACR. Gains of chromosomes 7 and 17 were found in 2 tumors, whereas chromosome 3p deletion and TFE3 translocations were not detected. In this study, we reported a sizable cohort of renal tumors seen in TSC and were able to identify them as different morphotypes, which may help to expand the morphologic spectrum of TSC-associated RCC.

Significance: We generated a thyroid-specific CreER transgenic mouse and used this strain to model progression of v-raf murine sarcoma viral oncogene homolog B ( BRAF )-mutant papillary thyroid cancer to anaplastic thyroid cancer (ATC). These murine tumors recapitulated the temporal progression and molecular hallmarks of human ATC. We demonstrated that combined mapk/Erk kinase (MEK) and BRAF inhibition resulted in enhanced antitumor activity vs. single-agent BRAF inhibitors in this preclinical model. This model represents a previously lacking mouse model of BRAF -mutant ATC and adds to the experimental armamentarium of a highly lethal disease in need of scientific advances. These data also suggest that potent inhibition of the MAPK pathway may improve outcomes in advanced thyroid cancers.

The 2004 World Health Organization classification of tumors defines epithelioid angiomyolipoma of kidney as a potentially malignant mesenchymal neoplasm with reported metastasis in approximately one-third of the cases. However, this conclusion was based primarily on individual case reports and small retrospective series. More recently reported larger series have shown varying results. We reviewed 437 consecutive renal angiomyolipomas with primary resection at three tertiary-care institutions with high nephrectomy volumes. Only tumors showing >80% epithelioid histology were included in this study. Tumors resected elsewhere and reviewed in consultation were not included. Twenty of these 437 (4.6%) were classified as epithelioid angiomyolipoma. The female to male ratio was 11:9, mean age 49.7 (range, 30–80) years, and mean tumor size 8.7 (range, 1–25) cm. Microscopic tumor necrosis was present in 10 (50%) tumors and mitotic activity (range, <1–5/10 high power fields) in 8 (40%); atypical mitoses were seen in only 1 (5%) tumor. Pleomorphic ganglion-like or multinucleated giant cells were seen in 18 (90%) tumors. With a mean follow-up of 82.5 (range, 1–356) months, seventeen patients were alive with no-evidence-of-disease at the time of last follow-up; two patients died of unrelated causes with no-evidence-of-disease, and one patient (5%) developed distant metastases. Our data, based on consecutively resected angiomyolipomas with long clinical follow-up, suggests that epithelioid angiomyolipomas constitute a small proportion of all angiomyolipomas, and the rate of aggressive behavior among epithelioid angiomyolipomas, even when showing morphologic features previously reported to portend aggressive clinical behavior, is very low.

Purpose: HPV-associated head and neck squamous cell carcinoma (HPV+HNSCC) is the most common HPV-associated malignancy in the United States and continues to increase in incidence. Current diagnostic approaches for HPV+HNSCC rely on tissue biopsy followed by histomorphologic assessment and detection of HPV indirectly by p16 IHC. Such approaches are invasive and have variable sensitivity. Experimental Design: We conducted a prospective observational study in 140 subjects (70 cases and 70 controls) to test the hypothesis that a noninvasive diagnostic approach for HPV+HNSCC would have improved diagnostic accuracy, lower cost, and shorter diagnostic interval compared with standard approaches. Blood was collected, processed for circulating tumor HPV DNA (ctHPVDNA), and analyzed with custom ddPCR assays for HPV genotypes 16, 18, 33, 35, and 45. Diagnostic performance, cost, and diagnostic interval were calculated for standard clinical workup and compared with a noninvasive approach using ctHPVDNA combined with cross-sectional imaging and physical examination findings. Results: Sensitivity and specificity of ctHPVDNA for detecting HPV+HNSCC were 98.4% and 98.6%, respectively. Sensitivity and specificity of a composite noninvasive diagnostic using ctHPVDNA and imaging/physical examination were 95.1% and 98.6%, respectively. Diagnostic accuracy of this noninvasive approach was significantly higher than standard of care (Youden index 0.937 vs. 0.707, P = 0.0006). Costs of noninvasive diagnostic were 36% to 38% less than standard clinical workup and the median diagnostic interval was 26 days less. Conclusions: A noninvasive diagnostic approach for HPV+HNSCC demonstrated improved accuracy, reduced cost, and a shorter time to diagnosis compared with standard clinical workup and could be a viable alternative in the future.