[Glomus cell clusters of the lymph node]

Nevus-cell aggregates in lymph nodes: Fine-needle aspiration cytologic findings and resulting diagnostic difficulties

We report a case of nodal nevus present in enlarged lymph nodes with changes of dermatopathic lymphadenopathy sampled by fine-needle aspiration (FNA) cytology prior to clinical evaluation of the patient. This lymph node pathology was established later by lymph node excisional biopsy, by which along with a skin biopsy the dermatopathic lymphadenopathy was tentatively attributed to early mycosis fungoides. The FNA revealed fairly atypical melanotic tissue from the dermatopathic lymphadenopathy along with nodules of uniform melanocytic nevoid cells, the presence of which in combination with the dermatopathic atypical tissue provided a tentative diagnosis of metastatic melanoma of unknown primary, with the diagnosis of nodal nevus presented as a less likely possibility. This is to our knowledge the first cytologic report on FNA of nodal nevus, which besides presenting cytologic findings of this entity highlights some of the problems related to providing an accurate diagnosis, if this exceptionally unusual pathologic entity is encountered in lymph nodes sampled for enlargement from pathologies unrelated to this entity. The subject of nevus changes in lymph nodes is briefly discussed.

Importance of tumor cells in axillary node sinus margins ('clandestine' metastases) discovered by serial sectioning in operable breast carcinoma

The prognostic implications of small emboli of carcinoma cells in the sinus margins of axillary lymph nodes ('clandestine' metastases) discovered by serial node sectioning at 2 mm intervals was analysed. All patients, previously untreated, were admitted between 1967 and 1978 and underwent mastectomy and axillary node dissection. Our study examined the risk of distant metastases of 1153 patients with from 0 to 3 involved axillary lymph nodes. A Cox multivariate analysis was performed, taking into account the classical prognostic factors (menopausal status, histoprognostic grade, and anatomic tumor size), and for nodal status including the notion of clandestine (CM) or parenchymal metastases (PM). Compared to patients without axillary metastases, patients with one node involved with CM had a relative risk of distant metastases of 1.7, identical to the risk for patients with one node with PM; and patients with one node containing PM and a second CM, had a relative risk of 2.2. Serial node sectioning discovers nodal metastases that would otherwise not be detected. These CM have important clinical implications and should be taken into account when considering adjuvant manipulations.

"Epithelioid" vascular cells in lymph nodes and evidence of glomus structures

Examination of more than 9,000 lymph nodes by light microscopy has shown epithelioid cell nests in 40 (6.7%) of 600 surgical specimens from operations for breast carcinoma. Such epithelioid cell nests have occasionally been described as "benign nevus cells in the capsule of lymph nodes". The present study shows that such cell foci are relatively frequent and that they originate from cells in the vascular walls. This vascular origin makes the observed spectrum of such structures glomus-like. They can often be identified at several foci and especially in the trabecular reticulum of a lymph node capsule. They measure between 35 microns and 150 microns and may be compared with capillary arteriovenous anastomoses. Five foci showed increased cellularity and even a tumorous expansion into the corticopulpal zone measuring up to 1,500 microns across. With the demonstration of a matrix of vascular muscle cells beneath the glomus-like structures, the relatively rare tumors are defined as "nodular capillary glomus cell proliferations".

[Glomus structures in axillary lymph nodes and the demarcation against metastases of mammary carcinoma (author's transl)]

A report is presented on the demonstration of epithelioid cell clusters within the axillary lymph node group, which could be taken for micrometastases of a mammary carcinoma. The lymph node material from 400 extensively excised mammary carcinomas with obligatory lymphonodectomy was available for this study. Metastases of mammary carcinoma were found in 264 cases (66%). Therewithal a procedure with microscopic inspection of successive sections at 100 mu intervals of all lymph nodes led to the discovery of epithelioid cell clusters in 18 out of the 400 cases examined. As regards their appearance and structural peculiarities, with direct allocation to the local vascular stroma, these clusters must be regarded as glomus-like structures. From a clinical point of view, their fundamental significance consists in the necessary differentialdiagnostic demarcation against micrometastases of carcinoma in the region of origin of the lymph.