Histopathologic Aspects of Malignancy-Associated Granuloma Annulare: A Single Institution Experience

Abstract

Granuloma annulare (GA) is a benign, self-limiting granulomatous inflammatory disease that exhibits different histologic patterns. Infrequently, granuloma annulare can be associated with malignancy, the so-called malignancy-associated granuloma annulare (MGA). In this study, we aimed to compare the clinical and histopathological differences between GA and MGA. We retrospectively reviewed patient charts and identified 35 patients diagnosed with GA and concurrent hematological or solid organ malignancies as a case group. Additionally, we identified 33 patients without any known solid organ or hematological malignancy as a control group. MGA is commonly seen in the seventh decade of life, while GA affects the younger population. MGA is most commonly presented in the extremities of the body. The most common malignancy associated with MGA was chronic lymphocytic leukemia. Prostate cancer was the most common type of solid organ malignancy that was associated with MGA. The most common histopathological pattern seen in MGA was interstitial, comprising half of the cases. Multinucleated giant cells were present in half of the MGA cases and in most of the control group. In the literature, there are no established features that distinguish MGA from GA. Although MGA and GA have overlapping features, in our series, we found that the interstitial pattern was more common in MGA, while the necrobiotic pattern was more common in GA.

Clinicopathologic evaluation of granuloma annulare: Study of 136 Iranian cases, south of Iran

“…21 Mucin was more frequently detected in the Malignancy-associated GA to control group. 18 In our study, 41.9% of patients had eosinophil that is higher than what other researchers observed in their studies (3.7%-38%). 16,[18][19][20][21] The possibility of insect bite or drug reactions are proposed as the causes of eosinophil-rich GA (20).…”

“…18 In our study, 41.9% of patients had eosinophil that is higher than what other researchers observed in their studies (3.7%-38%). 16,[18][19][20][21] The possibility of insect bite or drug reactions are proposed as the causes of eosinophil-rich GA (20). Giant cells (43.3%) were less frequent than some of the studies (57%-90%), 16,[18][19][20] but higher than some other studies (15.9%).…”

“…Also, necrobiotic GA was slightly more than the interstitial and mixed types in the GA cases not associated with malignancy. 18 Mucin was observed in all of our cases in haematoxylin and eosin (H&E) stain; however, in previous studies it was reported in 61%-93%. 16,[19][20][21] The difference between studies may be the result of detection of mucin in the H&E or mucin special stains.…”

“…In line with our research, in other studies extremities were the most affected area. 16,18 Malignancy-associated and childhood GA also presented on the extremities in most patients. 18,19 In most of the studies that assessed the histopathologic findings of GA, interstitial pattern was the more common type of GA and 33%-71% of cases demonstrated this pattern.…”

“…16,18 Malignancy-associated and childhood GA also presented on the extremities in most patients. 18,19 In most of the studies that assessed the histopathologic findings of GA, interstitial pattern was the more common type of GA and 33%-71% of cases demonstrated this pattern. 11,16,17,19,20 However, Cheng et al 21 showed palisading histiocytes as a predominant type of infiltration in GA (63.6%).…”