Müllerian-Type Clear Cell Carcinoma of Donor Origin in a Male Patient with a Kidney Transplant: Ascertained by Molecular Testing

Round 1

Reviewer 1 Report

The authors describe a rare case in which advanced molecular techniques were applied to investigate the nature and the origin of a malignancy. The case is interesting and the suggested evaluation of certain malignancies in kidney transplant recipients to determine whether the cancer is of donor origin is rational although not applicable everywhere. The manuscript is well-written.

For the above reasons, I suggest accepting the manuscript as is.

Author Response

The authors describe a rare case in which advanced molecular techniques were applied to investigate the nature and the origin of a malignancy. The case is interesting and the suggested evaluation of certain malignancies in kidney transplant recipients to determine whether the cancer is of donor origin is rational although not applicable everywhere. The manuscript is well-written. For the above reasons, I suggest accepting the manuscript as is.

Response: We thank the reviewer for their assessment.

Reviewer 2 Report

This is an interesting case of what appears to be donor derived mullerian clear cell carcinoma with fatal consequences in a renal transplant recipient and hence deserves to be reported.

A couple of points need to be clarified within the manuscript-

1) Intraperitoneal Mullerian clear cell carcinoma is an incredibly rare malignancy and often advanced diagnostic techniques are required to confirm the diagnosis. The authors need to place more emphasis on this aspect Molecular Landscape of Mullerian Clear Cell Carcinomas Identifies The Cancer Genome Atlas-like Prognostic Subgroups - ScienceDirect

2) All of the evidence points to the malignancy being transmitted with the allograft (ie the tumour arose from cells transplanted with the renal allograft). Where in the allograft do the authors believe the mullerian tissue was located (was it possibly in the renal pelvis)? Plus was it possible that the primary source remained occult (ie was not able to be detected via imaging/biopsy of the renal allograft). 

3) The CT scan image in Figure 1 C depicts a lesion in the renal allograft which appears to be solid in nature. Can the authors provide further information as to how this lesion was determined to be a cyst?

4) By the time the diagnosis was made it appears that the malignancy was well advanced. Mullerian CCC is known to be highly aggressive with often a poor outcome once the tumor is disseminated. However molecular profiling is now emerging as an important tool in order to try and ascertain what might be the best approach to take with respect to the choice of chemotherapy agents. This needs to be emphasized in the Discussion section.

Author Response

This is an interesting case of what appears to be donor derived mullerian clear cell carcinoma with fatal consequences in a renal transplant recipient and hence deserves to be reported. A couple of points need to be clarified within the manuscript-

1) Intraperitoneal Mullerian clear cell carcinoma is an incredibly rare malignancy and often advanced diagnostic techniques are required to confirm the diagnosis. The authors need to place more emphasis on this aspect Molecular Landscape of Mullerian Clear Cell Carcinomas Identifies The Cancer Genome Atlas-like Prognostic Subgroups - ScienceDirect

Response: We fully agree with the reviewer. To this end, we have expanded our discussion of the molecular landscape of Mullerian CCC, and how it compares to the present case. Lines 177-178, 219-229

“In particular, the SETD2 and NF2 somatic mutations are not commonly reported in Müllerian-type CCC [15,16], which is frequently characterized by mutations in ARID1A, PIK3CA, TP53, and PTEN [17]., Nor did our limited copy number evaluation reveal features associated with the TP53 mutant (surrogate for high copy number) and no specific molecular profile (surrogate for low copy number) subgroups defined by The Cancer Genome Atlas classifier of endometrial carcinomas and Müllerian-type CCC [17; 18].”

2) All of the evidence points to the malignancy being transmitted with the allograft (ie the tumour arose from cells transplanted with the renal allograft). Where in the allograft do the authors believe the mullerian tissue was located (was it possibly in the renal pelvis)? Plus was it possible that the primary source remained occult (ie was not able to be detected via imaging/biopsy of the renal allograft). 

Response: We share the reviewer’s interest in the potential origin of the Mullerian tissue and agree with the likelihood that it arose in the allograft. The allograft’s renal pelvis seems like an excellent possibility. However, without evidence of a primary on imaging and without pathological evaluation of the transplanted kidney, we find it challenging to conjecture the site. As the reviewer astutely points out, it  is very possible that the primary source remains occult. We have added a discussion of these points to the Discussion.  Lines 177-182

“We hypothesize that the tumor likely originated from ectopic Müllerian tissue transplanted along with the kidney transplant (e.g. the renal pelvis), which showed no radiographic or biopsy evidence of malignancy. Post-mortem pathologic evaluation of the kidney transplant was not conducted and there remains the possibility of an occult primary source that was not detected by imaging.”

3) The CT scan image in Figure 1 C depicts a lesion in the renal allograft which appears to be solid in nature. Can the authors provide further information as to how this lesion was determined to be a cyst?

Response: We appreciate the opportunity to clarify this important point. This hyperdense lesion on CT imaging was subsequently evaluated by MRI demonstrating T1 hyperintense signal (as shown in the newly added Figure 1D) without contrast enhancement (as shown in the newly added Figure 1E) thus suggestive of a proteinaceous/hemorrhagic cyst. We have revised the manuscript to include this information.

4) By the time the diagnosis was made it appears that the malignancy was well advanced. Mullerian CCC is known to be highly aggressive with often a poor outcome once the tumor is disseminated. However molecular profiling is now emerging as an important tool in order to try and ascertain what might be the best approach to take with respect to the choice of chemotherapy agents. This needs to be emphasized in the Discussion section.

Response: Thank you for highlighting this important point. We have emphasized this point in the discussion. Lines 236-238; 254-256.

Reviewer 3 Report

This case underscores the importance of molecular testing in diagnosing tumors of unknown primary origin in transplant patients. The emergence of Müllerian-type CCC from a donor in a transplant recipient is novel and emphasizes the value of NGS-based sequencing and STR analyses. These findings contribute to tailored treatment strategies for such rare and aggressive malignancies. some amendments are required:

 

• Clarity and Structure:
• The introduction could be more concise and organized. Consider condensing the information about CCCs and their usual sites of origin.
• The case presentation section is quite detailed and could benefit from better organization, possibly dividing it into subsections for clarity.
• Technical Terminology:
• There are several technical terms and acronyms used throughout the article. It might be helpful to provide brief explanations or expand the acronyms on first use to aid readers who are not familiar with the field.
• Sourcing and Citations:
• The article references several statistics and studies without direct citations. It's important to provide proper citations for these claims to ensure the accuracy and credibility of the information. Authors should read these novel papers and discuss them: PMID: 37446024; PMID: 37373581.
• Language and Readability:
• Some sentences are long and complex, making the text difficult to follow. Break them down or consider restructuring them for clarity.
• The article could benefit from simplifying some of the language, especially when discussing technical details. Ensure that the article is accessible to a broader audience, including those not specialized in the field.
• Consider filling in a dedicated conclusion paragraph for clarity.
• check typos 

 

Author Response

This case underscores the importance of molecular testing in diagnosing tumors of unknown primary origin in transplant patients. The emergence of Müllerian-type CCC from a donor in a transplant recipient is novel and emphasizes the value of NGS-based sequencing and STR analyses. These findings contribute to tailored treatment strategies for such rare and aggressive malignancies. some amendments are required:

Clarity and Structure:

1. The introduction could be more concise and organized. Consider condensing the information about CCCs and their usual sites of origin.

Response: We thank the reviewer for this guidance and have re-organized the introduction to make it more concise and clear. Lines 46-52

2. The case presentation section is quite detailed and could benefit from better organization, possibly dividing it into subsections for clarity.

Response: Thank you, we have added additional subsections to help with the organization. Lines 61, 71, 84, 124, 163

Technical Terminology:

3. There are several technical terms and acronyms used throughout the article. It might be helpful to provide brief explanations or expand the acronyms on first use to aid readers who are not familiar with the field.

Response: Thank you for this recommendation, we have now expanded all acronyms and defined them at first use.

Sourcing and Citations:

4. The article references several statistics and studies without direct citations. It's important to provide proper citations for these claims to ensure the accuracy and credibility of the information. Authors should read these novel papers and discuss them: PMID: 37446024; PMID: 37373581.

Response: Thank you, we have ensured that all findings that were cited from other publications have been properly cited in the text – namely citations 12-20 (lines 191-203, 217-229). We unfortunately were not able to perform miRNA or tumor microenvironmental analyses on this Mullerian-type clear cell carcinoma, although based on our comprehensive histopathological, immunohistochemical, and molecular analyses, we were able to rule out a renal cell carcinoma or other common types of genitourinary cancers. Future studies of the roles played by the tumor microenvironmental and miRNA in Mullerian CCC would be interesting.

Language and Readability:

1. Some sentences are long and complex, making the text difficult to follow. Break them down or consider restructuring them for clarity. The article could benefit from simplifying some of the language, especially when discussing technical details. Ensure that the article is accessible to a broader audience, including those not specialized in the field.

Response: Thank you, we have restructured longer sentences throughout the text for clarity and have endeavored to simplify some of our technical language.

2. Consider filling in a dedicated conclusion paragraph for clarity.

Response: We thank the reviewer for this recommendation and have added a dedicated conclusion for clarity. Lines 258-263

3. check typos

Response: Thank you, all spelling and grammar was checked.

Round 2

Reviewer 2 Report

The manuscript has benefitted from the revisions which have been undertaken.

Reviewer 3 Report

I believe that the study has sufficient merit to be considered for publication