RESUMEN
BACKGROUND: In the last three decades, axillary lymph node dissection (ALND) has been replaced by sentinel lymph node biopsy (SLNB) in all clinically node-negative patients. However, when SLNB alone is performed in clinically node-positive patients who are rendered node-negative by neoadjuvant chemotherapy, the procedure has a high false-negative rate and other complementary procedures have been described to improve its reliability. Preoperative tattooing of the suspicious lymph node with India ink at the time of biopsy, in addition to sentinel lymph node biopsy, is a reasonable alternative. The objective of our study is to determine, in clinically node-positive patients, the feasibility of tattooing suspicious axillary lymph node at the time of percutaneous needle biopsy and its retrieval at the time of surgery. METHODS: A prospective experimental study will be conducted divided into two phases-phases I and II. In phase I, 10 patients committed to undergo upfront surgery (without neoadjuvant chemotherapy) will have a suspicious lymph node tattooed by injecting India ink at the time of core needle biopsy. All patients will undergo a SLNB, during which the axilla will be inspected to determine if the tattooed lymph node can be visualized. Routine microscopic examination will follow, and concordance between the sentinel and tattooed node will also be established. In phase II, the process will be repeated for 30 patients who undergo surgery after neoadjuvant chemotherapy. The analysis will be performed in Stata version 12. DISCUSSION: There is a need to identify and test the techniques for the down-staged axilla in post-neoadjuvant chemotherapy patients, which are not only practical and limit the number of invasive procedures necessary but are representative of the new axillary status and help limit the extent of axillary surgery without negatively impacting outcomes. We propose that, for the patient undergoing neoadjuvant chemotherapy with a biopsy-proven disease in the axilla, this could be achieved by India ink which allows marking, identification, and retrieval of the biopsied lymph node. Retrieval of this previously biopsied lymph node along with sentinel nodes, if found to be representative of the status of the remainder of the axilla, could potentially eliminate the need for routine axillary lymph node dissection and thus limit morbidity. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03939598. Retrospectively registered on 7 May 2019.
RESUMEN
BACKGROUND: Central neurocytomas are rare neuronal neoplasms with a favorable prognosis. They are typically located in the lateral ventricles of the brain and mostly histologically correspond to WHO grade II with a Mib 1 labelling index of <2%. Similar tumors located in the cerebral hemispheres and spinal cord, for example, are called "extraventricular neurocytomas". A few tumors histologically show atypia, mitoses, vascular proliferation and/or necrosis and a Mib 1 index >2 % and are designated as "atypical neurocytomas. AIM: The aim of our study was to describe the common as well as unusual morphologic features and the role of various immunohistochemical stains in the diagnosis of these rare tumors. MATERIALS AND METHODS: We retrieved and reviewed 35 cases diagnosed between 2001 and 2015. RESULTS: Sixty percent of patients were males, and the mean age was 26 years. 31 cases (88.6%) were intraventricular and 4(11.4%) were extraventricular. Histologically, 6 cases (17.1%) were compatible with "atypical neurocytomas". All cases showed the classic morphology comprising nests and sheets of uniform, round cells with uniform round to oval nuclei with finely speckled chromatin and perinuclear cytoplasmic clearing (halos). All cases also showed delicate, fibrillary, neuropil-like matrices. Other common histologic features included capillary-sized blood vessels in a branching pattern in 57.1%, foci of calcification in 34.3% and perivascular pseudorosettes in 20%. Rare findings included Homer- Wright or true rosettes in 8.6% and ganglioid cells in 2.9%. Synaptophysin was the most consistent and valuable marker, being positive in almost all cases. GFAP positivity in tumor cells was seen in 25.7% of cases. Follow up was available in 13 patients. Of these 9 had histologically typical and 4 had atypical tumors. Only 1 (with an atypical neurocytoma) died, probably due to complications of surgery within one month, while 12 (including 3 with atypical neurocytomas) remained alive. Recurrence developed in 1 of these 12 patients (histologically consistent with typical morphology) almost 9 years after surgery. Only 4 patients, including 2 with atypical tumors, received postoperative radiotherapy, all with surgery in 2010 or later. Overall, prognosis was excellent with prolonged, recurrence free survival and most patients, even without receiving radiation therapy, were alive and well for many years, even a decade or more after surgery, without developing any recurrence, indicating the benign nature of these neoplasms.
