Sarcoid-like granulomas in renal cell carcinoma: The Houston Methodist Hospital experience

Sarcoid‑like granulomatous inflammation in a carotid body paraganglioma: A case report and mini‑review of the literature

Sarcoid-like granulomatous inflammation (SLGI) is defined as the development of non-necrotizing epithelioid granulomas in patients who do not meet the criteria for systemic sarcoidosis. Its occurrence is known to be linked to diverse conditions, including malignancies, infections, the use of certain drugs and inorganic substances. To the best of our knowledge, the available literature to date lacks any description regarding SLGI in a paraganglioma. The present study describes the first case of SLGI in a carotid body paraganglioma (CBP). A 54-year-old female patient presented with anterior neck swelling for 27 years without any other symptoms. An ultrasonography revealed a multinodular goiter with retrosternal extension and a solid lesion on the right side of the neck measuring 40x30x22 mm, which was suggestive of a CBP. The patient underwent a total thyroidectomy, and the right-side cervical mass was resected via another longitudinal incision. A histopathological examination of the thyroid specimen revealed findings of a multinodular goiter. Sections from the right-side cervical mass confirmed the diagnosis of CBP accompanied by multiple, well-formed, small-medium sized, non-necrotizing epithelioid granulomas associated with multinucleated giant cells, indicative of SLGI. Non-necrotizing epithelioid cell granulomas (as with SLGIs), identical to those observed in sarcoidosis, may rarely be observed in patients who do not meet the criteria of systemic sarcoidosis; however, they have been observed in association with various neoplasms. It is thus crucial to distinguish them from actual sarcoidosis, as misdiagnoses may lead to severe consequences. The presence of SLGIs accompanying a paraganglioma is an extremely rare phenomenon. Due to this, it is difficult to conclude if it confers a better prognosis or not.

Tumor-Associated Granulomas Preceding a Diagnosis of Thoracic Sarcoidosis: A Retrospective, Single-Center Cohort Study

There is a relationship between systemic sarcoidosis (SS) and malignancy. Sarcoidosis results from an exaggerated immune response in genetically susceptible individuals. In oncologic patients with sarcoidosis, tumoral antigens and antineoplastic treatment are considered potential triggering factors. The observation of a patient with granulomas in a parotid carcinoma who later developed SS led us to review the previous tumors of patients with SS. The aim of the study is to see whether granulomas were already present in the tumors that preceded sarcoidosis. We identified 196 sarcoidosis patients, 47 of whom had previously had a tumor. We were able to review 29 cases, 12 of which showed tumor-associated granulomas (TAGs) (41.4%). This ratio is much higher than that of the normal population (4.4–13.8). We analyzed five control patients without sarcoidosis for each tumor. In conclusion, we observed an increased number of TAGs in patients who later developed SS. This finding reinforces a pathogenic relationship between SS and neoplasia. The histology of tumors in patients with SS should be reviewed in an attempt to identify granulomas.

Granulomata in Clear Cell Renal Cell Carcinoma: An Uncommon Presentation of a Common Cancer, Not Two Separate Entities

Sarcoidal-like granulomata (SLG) are known to occur as a response to a variety of tumor types, including lymphomas, prominently seminoma, other miscellaneous carcinomas, and rarely in renal cell carcinoma. There have been a handful of previously reported cases in the literature of SLG occurring in association with RCC. Of those previously reported, none were associated with infection and only 3 patients had a history of sarcoidosis. The prognostic significance of SLG in RCC is unsettled and somewhat complicated by the relative rarity of its occurrence and the paucity of data therein. A case is presented of an otherwise histologically typical clear cell renal cell carcinoma with peri-tumoral and intra-tumoral SLG. Special stains were negative for organisms and past medical history was negative for sarcoidosis and connective tissue disease.

Epstein-Barr Virus-Associated Pulmonary Carcinoma: Proposing an Alternative Term and Expanding the Histologic Spectrum of Lymphoepithelioma-like Carcinoma of the Lung

Lymphoepithelioma-like carcinoma (LELC) of the lung is a rare Epstein-Barr virus (EBV)-associated carcinoma. It is histologically characterized by a syncytial growth pattern with marked lymphocytic infiltration that is indistinguishable from the histology observed in undifferentiated nasopharyngeal carcinomas. However, it has been noted that LELC can display nonclassic morphology and lack significant lymphocytic infiltration. In this study, we conducted a comprehensive clinicopathologic analysis of 61 patients with pulmonary LELC and performed automatic quantification of the lymphocytic infiltrate using the IHC Profiler software. We demonstrated that pulmonary LELCs have a morphologically continuous spectrum, ranging from classic poorly differentiated tumors with intense lymphocytic infiltration to nonclassic morphology with little lymphocytic infiltration. These EBV-associated tumors represent a distinct entity and usually occur in female and nonsmoking patients. Tumors with low lymphocytic infiltration can closely resemble nonkeratinizing squamous cell carcinoma and tend to be larger in size, have higher maximum standardized uptake values on radiography, and exhibit shorter times to recurrence than those with high lymphocytic infiltration. Through detailed pathologic examination, we observed several distinct morphologic features in pulmonary LELCs, including granulomatous inflammation, focal keratinization, spread through alveolar spaces, and lepidic spreading pattern. We also found that patients with tumors exhibiting granulomatous inflammation have favorable outcomes; however, spread through alveolar spaces did not significantly correlate with prognosis. As many of these "LELCs" do not resemble undifferentiated nasopharyngeal carcinoma or lymphoepithelioma, we propose using an alternative term, EBV-associated pulmonary carcinoma, to encompass the entire morphologic spectrum of this distinct disease entity.

Histologic Diagnosis of Renal Mass Biopsy

CONTEXT.—

Core biopsy has been increasingly used for clinical decision-making in the management of patients with renal masses. The sensitivity and specificity of histologic diagnoses of renal mass biopsies depend on many factors such as adequate sampling and tissue processing, diagnostic skill and experience, and appropriate use of ancillary techniques.

OBJECTIVE.—

To review the indications, emphasize the importance of obtaining adequate diagnostic material, and introduce a general diagnostic approach, in conjunction with immunohistochemistry, in diagnosis of renal mass biopsies.

DATA SOURCES.—

Literature review and personal experiences in daily practice and consultation diagnosis of renal masses in a large tertiary medical center.

CONCLUSIONS.—

For renal mass biopsies, it is critical to obtain adequate diagnostic material and establish a standard laboratory procedure in working with small biopsy specimens. The key for the diagnosis is to be familiar with different tumor entities with characteristic morphology and to understand the wide spectrum of tumor heterogeneity. By developing a systematic approach, one can categorize the tumor and create a sensible differential diagnosis based on the growth pattern and cellular morphology. Immunohistochemistry is particularly helpful for renal mass biopsy diagnosis in selected situations.