Treatment of Resistant TPM3::ALK + Fusion Protein Metastatic Inflammatory Myofibroblastic Tumor with ALK Targeting and Immune Checkpoint Inhibitor Combined Therapy

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This study reports the case of a young woman with metastatic ALK-rearranged TMI who was treated with ALK-rearranged inhibitors , according to resistance mutation and then a combination of doubled immunotherapy and ALK-is. This case is very interesting, but important details need to be adjusted and the discussion is too limited. Please find my comments below.

 

Introduction

- Lines 35-36: There is a repetition concerning the metastatic risk.

- Line 43: This sentence should be placed in the paragraph or adapted to focus it on treatment.

- Abbreviations such as ALKis are not used throughout the text (only from the discussion onwards).

- Line 50: Introductory sentence that summarizes the case report is too long and early (more suited to the beginning of a discussion).

 

Case:

- Lines 125-126: This sentence is repeated and adds nothing additional.

- Figure 1 C and D explanations are not in chronological order.

- Figure 2: l.100/101; this would need to be reworded.

- Figure 2: A cross-section with the description of pdl1 would be interesting.

- If the patient was re-biopsied, it would be interesting to include a figure concerning pdl1 for comparison.

 

Discussion

- Lines 125 to 132: This sentence has already been mentioned, and should be put in the introduction.

- Line 141: I disagree with "the most common"; I would say that it has already been described and that it is not the major partner. (See Antonescu et al., 2015)

- Line 160: A reference is missing

- Line 166: Further development is needed

- The discussion lacks of the most important aspect (response to immunotherapy), with little comparison in litterature to cases treated with immunotherapy or a combination of immunotherapy and ALKis, whether for IMT or other tumors.

There is a paragraph lacking development of references regarding the rationale for combined ALKis and immunotherapy treatment and a discussion of the rational.

 

Conclusion:

- 169-173 The sentence is too general and has already been repeated several times in the text. - 176-177 I do not entirely agree with this concluding sentence, because the main focus of this case report remains the response to immunotherapy/alkis and especially to the combination. Even if we have a tumor genetic analysis, a histological or molecular argument for treating the patient would be interesting.

Author Response

Comment 1: Lines 35-36: There is a repetition concerning the metastatic risk.

Response 1: I agree. Will rephrase it to avoid the repetition

Comment 2: Line 43: This sentence should be placed in the paragraph or adapted to focus it on treatment.

Response 2: I agree. I will change the sentence so clarify that the reason I mentioned the ALK mutation is for the targeted therapy

Comment 3: Abbreviations such as ALKis are not used throughout the text (only from the discussion onwards).

Response 3: I agree. Will start using abbreviations from the beginning 

Comment 4: Line 50: Introductory sentence that summarizes the case report is too long and early (more suited to the beginning of a discussion).

Response 4: I agree. I will change the location of the summary sentence

Case:

Comment 5: Lines 125-126: This sentence is repeated and adds nothing additional.

Response 5: I am not sure what sentence you are referencing. Those lines are from the discussion

Comment 6: Figure 1 C and D explanations are not in chronological order.

Response 6: Will resolve this in revised version

Comment 7: Figure 2: l.100/101; this would need to be reworded.

Response 7: Could you please be more specific? 

Comment 8: Figure 2: A cross-section with the description of pdl1 would be interesting.

Response 8: PDL1 was not stained for. I will explain further in the revised version the rationale for the selection of PD1 inhibitors

Comment 9: If the patient was re-biopsied, it would be interesting to include a figure concerning pdl1 for comparison.

Response 9: patient was not re-biopsied 

Discussion

Comment 10: Lines 125 to 132: This sentence has already been mentioned, and should be put in the introduction.

Response 10: I agree that it has already been mentioned. Should I start the discussion by diving directly into ALK inhibitors and how they work?

Comment 11: Line 141: I disagree with "the most common"; I would say that it has already been described and that it is not the major partner. (See Antonescu et al., 2015)

Response 11: I agree with changing how the information is presented. However, it's been reported that >50% of IMTs harbor this fusion protein, hence my rationale for writing "The most common". I will change this

Comment 12: Line 160: A reference is missing

Response 12: The information provided in that sentence (lines 159-162) is from the same reference

Comment 13: Line 166: Further development is needed

- The discussion lacks of the most important aspect (response to immunotherapy), with little comparison in litterature to cases treated with immunotherapy or a combination of immunotherapy and ALKis, whether for IMT or other tumors.

There is a paragraph lacking development of references regarding the rationale for combined ALKis and immunotherapy treatment and a discussion of the rational.

Response 13: I agree that this is an important topic to discuss. I will revise the manuscript and add relevant information regarding the response to immunotherapy. Additionally, I will elucidate the rationale for how we switched between ALKi

Conclusion:

Comment 14: 169-173 The sentence is too general and has already been repeated several times in the text.

Response 14: I agree. I will edit this in the revised version

Comment 15: 176-177 I do not entirely agree with this concluding sentence, because the main focus of this case report remains the response to immunotherapy/alkis and especially to the combination. Even if we have a tumor genetic analysis, a histological or molecular argument for treating the patient would be interesting.

Response 15: In the updated manuscript, I will provide a more detailed histological and molecular argument for the selection of the therapies. I am currently working with the pathologist to obtain the relevant data

 

I will try to upload the revised document within the week. As soon as we have all the information from all the departments involved

Reviewer 2 Report

Comments and Suggestions for Authors

The authors presented a case of metastatic IMT with TPM3::ALK1 fusion that developed therapeutic resistance to ALK1 targeted therapies, and was subsequently successfully controlled by combination therapy. This case is of clinical significance to highlight the challenge of therapeutic resistance to ALK-targeted therapy in IMTs and add to the literature regarding the efficacy of combination therapy. The

Major comments:

1. In the background and discussion (e.g. Page 2 43-46; Page 4 131-132; page 5 145-146), the authors stated that ALK fusion, particularly TPM3::ALK, may confer more aggressive or metastatic potential. Although there were few references of basic research studies that the authors cited, however, the statement could be misleading to the audience outside of the field. As current clinicopathologic studies have not been able to reveal ALK fusions as a prognostic indicator for IMTs. In fact, data suggested that ALK-negative IMTs may have a higher likelihood of metastasis (see reference such as: Coffin CM, Hornick JL, Fletcher CD. Inflammatory myofibroblastic tumor: comparison of clinicopathologic, histologic, and immunohistochemical features including ALK expression in atypical and aggressive cases. Am J Surg Pathol. 2007 Apr;31(4):509-20. doi: 10.1097/01.pas.0000213393.57322.c7. PMID: 17414097). Recommend to revise the relevant content in this article, and focus on the therapeutic course rather than the role of TPM3::ALK fusion in disease progression.

 

2. Was the metastatic tumor tested for PD-L1 expression to support the rationale of the application of immunotherapy? Please add relevant immunohistochemistry (e.g. pathologic images) or molecular data regarding PD-L1 expression.

 

3. For the completion of the case report, it would be useful to add the pathologic images of the primary lung tumor.

 

4. In the page 4 line 120, “She has experienced no disease progression, and all lesions remain stable or have decreased in size”. Please clarify: what was the status of the thigh mass at the latest follow up? Any other local control therapies (such as radiation therapy) used for any lesions during the course of combination therapy?

Minor comments:

1. Recommend to use the updated expression for fusions (e.g. TPM3-ALK to TPM3::ALK)
2. Page 2 line 54: Suggest removing the patient initials and add information demonstrating that the ethical aspect was met.

 

3. Page 2 line 59: Suggest remove “initial pathology suggested histiocytic sarcoma”. Although one can understand a correct pathologic diagnosis is essential and molecular analysis contributes to the correct diagnosis. This information is not relevant to the main aim of the article.

 

Author Response

Comment 1: In the background and discussion (e.g. Page 2 43-46; Page 4 131-132; page 5 145-146), the authors stated that ALK fusion, particularly TPM3::ALK, may confer more aggressive or metastatic potential. Although there were few references of basic research studies that the authors cited, however, the statement could be misleading to the audience outside of the field. As current clinicopathologic studies have not been able to reveal ALK fusions as a prognostic indicator for IMTs. In fact, data suggested that ALK-negative IMTs may have a higher likelihood of metastasis (see reference such as: Coffin CM, Hornick JL, Fletcher CD. Inflammatory myofibroblastic tumor: comparison of clinicopathologic, histologic, and immunohistochemical features including ALK expression in atypical and aggressive cases. Am J Surg Pathol. 2007 Apr;31(4):509-20. doi: 10.1097/01.pas.0000213393.57322.c7. PMID: 17414097). Recommend to revise the relevant content in this article, and focus on the therapeutic course rather than the role of TPM3::ALK fusion in disease progression.

Response 1: I agree with the fact that there is no definitive data about how the ALK fusion protein is a prognostic indicator. I will focus more on the therapeutic study and will edit the statement by emphasizing how there is conflicting data and how this topic needs to be further explored

Comment 2: Was the metastatic tumor tested for PD-L1 expression to support the rationale of the application of immunotherapy? Please add relevant immunohistochemistry (e.g. pathologic images) or molecular data regarding PD-L1 expression.

Response 2: the tumor was tested for PD-L1 expression and it tested negative. I will upload a revised version describing our rationale for choosing a PD1 inhibitor

Comment 3: For the completion of the case report, it would be useful to add the pathologic images of the primary lung tumor.

Response 3: I agree with this point. However, the initial imaging was done outside the country and we were not able to obtain the initial images. The only images we have are those post lobectomy

Comment 4: In the page 4 line 120, “She has experienced no disease progression, and all lesions remain stable or have decreased in size”. Please clarify: what was the status of the thigh mass at the latest follow up? Any other local control therapies (such as radiation therapy) used for any lesions during the course of combination therapy?

Response 3: I will clarify the status of the thigh mass at the last follow-up. No other therapy was used during her combination therapy as she responded very well to it. All other therapies she received (radiation, surgery) have already been described in the report

Minor comments:

Comment 5: Recommend to use the updated expression for fusions (e.g. TPM3-ALK to TPM3::ALK)

Response 5: Will update in revised manuscript  

Comment 6: Page 2 line 54: Suggest removing the patient initials and add information demonstrating that the ethical aspect was met.

Response 6: Will update in revised manuscript 

Comment 7: Page 2 line 59: Suggest remove “initial pathology suggested histiocytic sarcoma”. Although one can understand a correct pathologic diagnosis is essential and molecular analysis contributes to the correct diagnosis. This information is not relevant to the main aim of the article.

Response 7: I agree. Will update in revised manuscript 

 

I will try to upload the revised document within the week. As soon as we have all the information from all the departments involved

Reviewer 3 Report

Comments and Suggestions for Authors

I think this is a very worthwhile case report to help guide oncologists in the care of patients with this rare tumor. My major issue is that I wasn't clear on the thought process of why one drug was being swapped for another (aside from the initial criz->cert transition which was explained with the point mutation) - I think this is an absolutely critical aspect of precision oncology care that needs to be more clearly explained in the report. I tried to call out the main areas where this is an issue in my comments below. 

1) Please cite the panels in order in the figure legend. In figure 1, the legend cites (D) prior to (C). In addition, please add a title for the figure. The way it is now, when you look at it initially it appears that "PET image" is the title of the figure but the figure clearly has different imaging modalities.

2) Bottom of page 3: Please explain why alectinib was selected after failure of ceritinib and why the cough, DOB and persistent fever prompted another ALKi change - was this thought to be side effect? Or did you think there was disease progression? Based on symptoms alone or other data? Also, in lines 70-73, it is stated that the resistance mutation found in this patient is often detected after alectinib therapy (line 72). So, please explain why the team thought alectinib would be effective.

3) How is the strabismus related? Is this thought to be drug effect? Tumor side effect?

4) In the discussion, please add more of a discussion of the mechanism of resistance of I1171S and what drugs are impacted by this mutation. Is it only criz and ceritinib? Or is alectinib also effected? Is that why she failed alectinib? What is it about lorlatinib that makes it a better choice against this mutation? Lorlatinib has a very different chemical structure than the other ATP-competitive ALKi and that gives it a different activity profile against resistance mutations - please add more data and details about the evolution of ALKi therapy for this patient.

5) Lines 155-157: You discuss several mechanisms of ALKi resistance beyond simple point mutations. Do you think these are in play for this patient? Please tie this statement to your patient case (meaning, either you don't think these are relevant for your patient but you want to mention so people are aware of the landscape of resistance to ALKi; or, you do think they are relevant to your patient and then explain how).

6) Lines 166-167: Do the case reports on IMT and NSCLC suggest that ALK positivity contributes or impacts the response to immunotherapy? Please clarify the point you are trying to make in these lines.

7) Line 170: extra period (minor typo)

8) Lines 176-177: Your conclusions gets at my prior question: if the report is meant to highlight the importance of molecular and genetic testing, then I think it needs to be more clear within in the text how the decisions were made to switch between ALKis. Also, it seems there were three ALKi transitions (criz-cert-alectinib-lorlatinib) however, molecular testing was only done on the initial tumor and on a sample taken in the criz-cert transition. Why wasn't further molecular testing done?

 

 

 

 

Author Response

Comment 1: Please cite the panels in order in the figure legend. In figure 1, the legend cites (D) prior to (C). In addition, please add a title for the figure. The way it is now, when you look at it initially it appears that "PET image" is the title of the figure but the figure clearly has different imaging modalities.

Response 1: Resolved in updated version

Comment 2: Bottom of page 3: Please explain why alectinib was selected after failure of ceritinib and why the cough, DOB and persistent fever prompted another ALKi change - was this thought to be side effect? Or did you think there was disease progression? Based on symptoms alone or other data? Also, in lines 70-73, it is stated that the resistance mutation found in this patient is often detected after alectinib therapy (line 72). So, please explain why the team thought alectinib would be effective.

Response 2: I agree with your point. I will explain why we chose different ALKi and the rationale for each of them

Comment 3: How is the strabismus related? Is this thought to be drug effect? Tumor side effect?

Response 3: We thought it was a combination of both. I mentioned it to describe the whole story

Comment 4: In the discussion, please add more of a discussion of the mechanism of resistance of I1171S and what drugs are impacted by this mutation. Is it only criz and ceritinib? Or is alectinib also effected? Is that why she failed alectinib? What is it about lorlatinib that makes it a better choice against this mutation? Lorlatinib has a very different chemical structure than the other ATP-competitive ALKi and that gives it a different activity profile against resistance mutations - please add more data and details about the evolution of ALKi therapy for this patient.

Response 4: I agree that this topic needs further explanation. I will explain in the revised version the mechanism of resistance of that mutation, as well as a possibility of why Lorlatinib worked better

Comment 5: Lines 155-157: You discuss several mechanisms of ALKi resistance beyond simple point mutations. Do you think these are in play for this patient? Please tie this statement to your patient case (meaning, either you don't think these are relevant for your patient but you want to mention so people are aware of the landscape of resistance to ALKi; or, you do think they are relevant to your patient and then explain how).

Response 5: I will tie this to the patient. I don't think they play a role in this patient, but I wanted to give the readers an overview of the different mechanisms of resistance

Comment 6: Lines 166-167: Do the case reports on IMT and NSCLC suggest that ALK positivity contributes or impacts the response to immunotherapy? Please clarify the point you are trying to make in these lines.

Response 6: I just wanted to mention that despite no clinical guidelines existing for combined treatment, several reports suggest it could be a viable solution

Comment 7: Line 170: extra period (minor typo)

Response 7: Resolved

Comment 8: Lines 176-177: Your conclusions gets at my prior question: if the report is meant to highlight the importance of molecular and genetic testing, then I think it needs to be more clear within in the text how the decisions were made to switch between ALKis. Also, it seems there were three ALKi transitions (criz-cert-alectinib-lorlatinib) however, molecular testing was only done on the initial tumor and on a sample taken in the criz-cert transition. Why wasn't further molecular testing done?

Response 8: See response 2. Molecular testing was performed twice on the tumor, using NGS. I will describe the results in the revised version 

I will try to upload the revised document within the week. As soon as we have all the information from all the departments involved

Reviewer 4 Report

Comments and Suggestions for Authors

Leonardo Simonelli et al. reported a rare metastatic IMT case with ALK aberration and initially managed with several cycle of ALK inhibitors. Subsequent disease progression was accompanied by emergence of a novel ALK mutation identified. A combination of mutation-overcoming ALK inhibitor and immune checkpoint inhibitors achieved a stable or decreased tumor status. This case provided a new combination strategy for ALK mutated IMT.

 

I have the following comments:

1. author mentioned that the molecular profiling was performed (Line 70), is this an NGS sequencing? Before and after the treatment, is there any other mutations or aberrations present that may affecting the treatment outcome.

 

2. Was tumoral PD-L1 expression status or tumor mutational burden assessed prior to immune checkpoint inhibitor administration? These biomarkers require elucidation given their established predictive value in immunotherapy response

 

3. Were serial plasma circulating tumor DNA (ctDNA) analyses performed to monitor dynamic ALK mutational evolution? Such liquid biopsy approaches could potentially enable earlier detection of molecular progression preceding radiographic changes.

Author Response

Comment 1: author mentioned that the molecular profiling was performed (Line 70), is this an NGS sequencing? Before and after the treatment, is there any other mutations or aberrations present that may affecting the treatment outcome.

Response 1: It was NGS sequencing, performed twice. I will describe the results in the revised version. No other mutations were detected. 

Comment 2: Was tumoral PD-L1 expression status or tumor mutational burden assessed prior to immune checkpoint inhibitor administration? These biomarkers require elucidation given their established predictive value in immunotherapy response

Response 2: PDL1 expression was negative. We decided to use immunotherapy as the tumor samples showed several Tumor Infiltrating Lymphocytes (TILs), prompting us to attempt immunotherapy. I will add this information in the revised version

Comment 3: Were serial plasma circulating tumor DNA (ctDNA) analyses performed to monitor dynamic ALK mutational evolution? Such liquid biopsy approaches could potentially enable earlier detection of molecular progression preceding radiographic changes.

Response 3: ctDNA analysis was performed, however, it wasn't able to detect any molecular changes. Because of the negative results and because we only performed it once, I did not mention it in the manuscript. 

 

I will try to upload the revised document within the week. As soon as we have all the information from all the departments involved

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Good revisions.

A few comments nonetheless:

Case: L 104 : Is PDL1 analyzed by NGS or immunohistochemistry?

Discussion :

• *There's a missing summary sentence at the beginning.
• The first paragraph is too descriptive, with no direct connection to the case.
• L177 : remove "suggesting" to put "and" ; there is no cause and effect relationship
  

Comments on the Quality of English Language

Legends are too long

Author Response

Comment 1: L 104 : Is PDL1 analyzed by NGS or immunohistochemistry?

Response: PDL1 is analyzed by NGS, it's specfied on line 118, right after Figure 2

Discussion :

Comment 2: There's a missing summary sentence at the beginning. The first paragraph is too descriptive, with no direct connection to the case.

Response 2: resolved, added a quick summary sentence, and summarized first paragraph and connected it to the case

Comment 3: L177 : remove "suggesting" to put "and" ; there is no cause and effect relationship

Response 3: done

Comment 4: Legends are too long

Response 4: Resolved

Reviewer 2 Report

Comments and Suggestions for Authors

1. Page 2 figure 2 caption: it was described that the neoplasm is "in an inflammatory backdrop consisting of multiple tumor-infiltrating lymphocytes (TILs)". However, IMT itself carries the inflammatory infiltrates as a characteristic histologic feature. How do you justify these lymphocytic infiltrates are TILs, rather than a common characteristic finding in IMT?

Author Response

Comment 1: Page 2 figure 2 caption: it was described that the neoplasm is "in an inflammatory backdrop consisting of multiple tumor-infiltrating lymphocytes (TILs)". However, IMT itself carries the inflammatory infiltrates as a characteristic histologic feature. How do you justify these lymphocytic infiltrates are TILs, rather than a common characteristic finding in IMT?

Response 2: TILs were identified from their histologic appearance compared to the inflammatory infiltrate that IMT inherently has. The TILs were noted to be dense infiltrates within tumor nests or in direct contact with tumor cells,  clustered near viable tumor, they were dense and organized, and some showed signs of activation (prominent nucleoli, cytoplasmic granules)

Reviewer 3 Report

Comments and Suggestions for Authors

Thank you for the revisions, the paper is now much more clear. The one last minor edit I recommend is to clarify what the NGS cited in lines 104-106 showed ("Repeat NGS sequencing showed sensitivity to alectinib and it was the only one we could obtain within a reasonable timeframe.") When you say that NGS showed sensitivity to alectinib, do you mean that the clone reverted back to the TPM3::ALK without the resistance mutation? Please clarify. 

 

Author Response

Comment 1: The one last minor edit I recommend is to clarify what the NGS cited in lines 104-106 showed ("Repeat NGS sequencing showed sensitivity to alectinib and it was the only one we could obtain within a reasonable timeframe.") When you say that NGS showed sensitivity to alectinib, do you mean that the clone reverted back to the TPM3::ALK without the resistance mutation? Please clarify. 

Response 1: The first NGS we performed showed a mutation that is often observed after disease progression while on Crizotinib or Alectinib. However, it also showed that the tumor was sensitive to Alectinib. I think the confusion arises from the first statement. I changed the statement to: "by NGS confirmed the presence of an ALK pathogenic variant (Exon 22, p.I1171S), often detected following progression on crizotinib or alectinib, supporting resistance to crizotinib while demonstrating potential sensitivity to alectinib and ceritinib. " When she then progressed on ceritinib, we repeated NGS and she the tumor was stills ensitive to Alectinib, so we switched to it. I didn't revert back, the mutation was always sensitive to alectinib, even if that specific mutation has been observed in other tumors when they progress on alectinib

Reviewer 4 Report

Comments and Suggestions for Authors

The author has addressed my questions, I have no further comments on the revised manuscript.

Author Response

Comment 1: The author has addressed my questions, I have no further comments on the revised manuscript.

Response 1: thank you