Primary Cutaneous Gamma-Delta T Cell Lymphomas: A Case Series and Overview of the Literature

Round 1

Reviewer 1 Report

This is a well-written singe institution series describing the pathologic and clinical features of cutaneous gamma delta T-cell lymphoma.  The authors discuss in relevant detail the histology, immunophenotype, molecular genetics, and clinical features/outcomes of a series of 20 cases of this rare entity.  Based on histology, the authors distinguish DE-GDTCL (MF-like) from S-GDTCL (SPTCL-like).  There have been other series and meta-analyses of this group of diseases, and this paper adds to the body of literature.  Furthermore, there are several important learning points that are novel or rarely described in this paper, which provides a high resolution of pathologic data in the studied patients.   This includes the discussion of a prior history of classic MF in a subset of 4 patients prior to the dx of PCGDTCL, with neoplastic infiltrates that appeared to undergo phenotypic switching/transformation with matching clonality studies between the MF and PCTGDTCL lesions in two of these patients.  I have also seen this twice retrospectively patients with PCGDTCL, and believe that it is underrecognized/underreported.  Of the 3 cases that were negative for TCR delta, 2 were positive to TCR gamma with the other being TCR "silent", which is interesting to note, as many institutions have access to one or the other, but not both.   The authors also discuss Vd1 vs Vd2 expression and metion that CCR4 expression is mostly absent, observations which are both interesting and potentially clinically relevant. 

Minor corrections recommended below: 

Figure 1 (B,C):  Please increase the brightness of these to images.  The label for figure C is missing.

Line 38: spelling of alpha/beta

Line 91: I recommend changing it from ". . . or also known as Ketron-Goodman disease"; to ". . . previously designated as Ketron-Goodman disease."

Line 225: one anatomic site (not sites)

Author Response

Thank you for your comment and your appreciation of our work.

The brightness of Figure 1 (B,C) has been increased and the label for C is now in place. The other minor corrections have been addressed, as requested.

Furthermore, the manuscript has undergone extensive language revision by an English native speaker.

Reviewer 2 Report

Silvia Alberti-Violetti and colleagues' manuscript entitled "Primary cutaneous T-cell lymphoma with gamma-delta phenotype: case series and overview of the literature." summarizes the clinical, morphological, immunophenotypic and molecular features of a cohort of 20 PCGDTCL from a single experienced centre.

The manuscript itself is fascinating as it reports the main features of a not small number of such rare neoplasms, of which not much is known yet.

I have only some minor points/suggestions:

• The text is sometimes non-flowing and challenging to read, especially in the Results section; it would benefit from an extensive review for clarity.

Author Response

Thank you for your comment and your kind words of appreciation for our work.

As requested, the manuscript has undergone extensive language revision by an English native speaker.