Frozen section can sometimes but not always be used to diagnose HTT. When HTT is diagnosed by its trabecular pattern through the use of frozen section, it may prevent total thyroidectomy.

Endometrial stromal tumors (ESTs) with limited infiltration were first proposed by Dionigi et al.(1) However, the prognostic significance of these tumors is unclear. We report a case of a 60-year-old woman who presented with a prolapsed uterine corpus and then underwent laparoscopic-assisted vaginal hysterectomy. A very small EST was incidentally found. The tumor manifested focal irregularity and finger-like permeation into the adjacent myometrium not exceeding 3 mm but exceeding 3 in number, features intermediate between a low-grade endometrial stromal sarcoma and an endometrial stromal nodule. By definition, we rendered a descriptive diagnosis of "endometrial stromal tumor with limited infiltration." A subsequent staging operation confirmed metastasis and, hence, a malignant potential.

Malic enzymes (MEs) are involved in fatty acid biosynthesis and lipid accumulation, and their expression in sebocytes and sebaceous lesions has not been investigated. The aims of this study were to examine ME1 and ME2 expression in normal skin and sebaceous lesions. A total of 68 cases including 5 specimens of normal skin, 12 facial lesions showing sebaceous hyperplasia, 18 sebaceous adenomas, 10 sebaceomas, 13 steatocystomas, and 10 sebaceous carcinomas were examined for the expression of ME1 and ME2. All benign and malignant sebaceous lesions showed ME1 in clear cells and ME2 in nonclear cells, respectively. ME1/ME2 phenotype is seen in basal sebocytes, basal keratinocytes, sweat glands, and outer root sheath cells and hence not specific. This study demonstrates that ME1/ME2 expression phenotype may have a potential to be a valuable marker for sebaceous differentiation. It is necessary to perform large-scale studies including skin tumors with a clear cell morphology that may mimic sebaceous differentiation.