Axillary lymph node treatment in breast cancer: an update.

Sentinel lymph node biopsy (SLNbx) is the standard of care for staging of breast cancer. Patients with a negative sentinel lymph node biopsy (SLNbx) do not undergo axillary lymph node dissection (ALND) or regional nodal irradiation (RNI). However, if a patient has a positive sentinel lymph node biopsy (SLNbx), then axillary lymph nodal dissection (ALND) is the standard treatment. Recent studies, notably the Z-0011 and MA-20 trials, have demonstrated that omission of axillary lymph nodal dissection (ALND) did not decrease overall survival. MA-20 demonstrated that inclusion of regional nodal irradiation (RNI) in addition to axillary lymph nodal dissection (ALND) did increase survival when compared to axillary lymph nodal dissection (ALND) without regional nodal irradiation (RNI). Ongoing studies are randomizing patients to axillary lymph nodal dissection (ALND) or regional nodal irradiation (RNI) after a positive sentinel lymph node biopsy (SLNbx).

Serial monitoring of humoral antibody-mediated rejection of cardiac allografts by C4d staining of interstitial capillaries.

C4d "staining" of interstitial capillaries of endomyocardial biopsies serves as an indicator of a humoral component of cardiac allograft rejection. In the present study, two cardiac allograft recipients were monitored serially for both cellular and humoral rejection. Cellular rejection, evaluated by light microscopy, and humoral rejection, judged by C4d immunofluorescent "staining", were treated with appropriate immunosuppressants. Weekly serial biopsies of the first patient revealed maximal humoral rejection (3+) after 1 week but diminished to 2+ thereafter. Cellular rejection was graded as 3A after 3 weeks but declined steadily to negligible cellular rejection through week 15. Whereas, cellular rejection peaked at 14-21 days, humoral rejection was greatest in the early post-transplant period. Biopsies of the second patient for 12 weeks revealed grade 1A to 1B moderate cellular rejection. Humoral rejection peaked at 3+ "staining" for C4d after 1 week transplant, and then wavered between 2+ (moderate "staining") and 1+ (weak "staining"). Results revealed the significance not only of traditional light microscopy in evaluating the severity of cellular rejection in endomyocardial biopsies of cardiac allotransplants, but also the value of C4d immunofluorescent "staining" of interstitial capillaries as an indicator of humoral rejection episodes, which may require modified therapy.

Aberrant myeloid marker expression in precursor B-cell and T-cell leukemias.

The World Health Organization (WHO) characterization of the immunophenotype of precursor B-cell acute lymphoblastic leukemia (pre-B ALL) includes the possible expression of myeloid cluster of differentiation (CD) markers CD13 and CD33. In precursor T-cell acute lymphoblastic leukemia (pre-T ALL), myeloid markers CD13 and CD33 are frequent while CD117 is rare. In the present investigation, 71 cases of confirmed pre-B ALL were evaluated for the presence of CD13 and CD33. Of the 19 (27%) cases that positively expressed myeloid markers, 10 (53%) expressed CD13, 17 (89%) expressed CD33, and 1 (5%) expressed CD117. Eight (42%) expressed both CD13 and CD33, and 1 (5%) expressed CD13, CD33, and CD117. Twenty-one cases of confirmed pre-T ALL were analyzed for myeloid markers CD13, CD33, CD117, and MPO. Of the 6 (29%) expressing myeloid markers, 4 (67%) were positive for CD13, 4 (67%) for CD33, 3 50(%) for CD117, and 1 (17%) for MPO. One (17%) was positive for both CD13 and CD117; one (17%) for CD13 and CD33; one (17%) for CD13, CD33 and CD117; and one (17%) for CD13, CD33 and MPO. These markers portend a poor prognosis compared to ALL cases without myeloid antigens, and a poor response to drug therapies targeting conventional ALL. Future studies will be directed to correlation of these markers with prognosis and therapeutic response, as well as whether drug therapies targeting myeloid antigens could be of use in treatment.

Aberrant expression of T-cell markers in acute myeloid leukemia.

According to WHO, several T-cell immunophenotypic markers may be aberrantly expressed in acute myeloid leukemia (AML). TdT may be expressed in greater than one-third of cases, and CD2 and CD7 may be expressed frequently at low intensity; however, the T-cell lineage specific antigen CD3 is usually absent. In this investigation, 30 cases of AML were evaluated for CD2, CD3, CD5, CD7, CD8 and TdT expression, and mean fluorescence intensities (MFI). Of the 3 (10%) cases positive for CD3 and CD8, 1 was bright (MFI>501), and 2 cases were moderate. TdT was moderately expressed in 4 (13.3%) cases with MFI values between 301 and 500. CD2 and CD5 were positive in 5 (16.7%) cases. While CD2 was moderate in all 5 cases, CD5 was bright in 3, moderate in 1 and dim in 1. Of the 15 (50%) cases positive for CD7, 9 were bright, 5 were moderate, and 1 was dim with a MFI value between 201 and 300. These data indicate that CD2 and CD7 may be frequently expressed at greater intensities than WHO specified. These results point to the need for a more extensive study to evaluate the potential prognostic significance of aberrant T-cell marker expression in AML.

Zap-70 and CD38 as predictors of IgVH mutation in CLL.

Zeta-chain (TCR)-associated protein kinase 70 kDa (Zap-70) and CD38 expression may be of prognostic significance in chronic lymphocytic leukemia (CLL). Previous studies indicate that Zap-70 and CD38 are usually positive in cases of CLL with unmutated immunoglobulin variable region genes (IgVH) and may be used to predict IgVH mutation status and prognosis. Usually cases of CLL positive for Zap-70 or CD38 indicate a worse prognosis. In the present investigation, 47 cases of CLL were evaluated for CD38 expression, and 17 cases were evaluated for both Zap-70 and CD38 expression. Of the 47 cases, 19 (40.4%) positively expressed CD38. Of the 17 cases evaluated for Zap-70, 11 (64.7%) were positive for Zap-70, while only 6 (35.3%) were positive for CD38 expression; the remaining cases were negative for CD38. The results of this study show that Zap-70 expression may be a better indicator of the mutational status of IgVH and prognosis of CLL than CD38 expression. In addition, CD38 negativity does not necessarily indicate that IgVH mutation has occurred. These data point to the need for a more extensive study to evaluate the significance of Zap-70 and CD38 expression as indicators of IgVH mutation status and prognosis of CLL patients.